Introduction: Combination CNC Machine and 3D Printer

About: is an Engineer with a background in electronics, optics, mechanical designs, chemistry, plastic injection molding and plastic die tooling.

How to make your own 2D CNC machine that converts into a 3D Printer and back to a CNC machine in less than an hour. Costing less than a CNC machine or 3D printer! (~$1,000.00) In addition, the design will go further than the traditional 3D printer printing ABS/PLA, and move forward to printing with new materials such as 3D Printing Nylon derivatives like tauman 618 as well as Acrylic and PET.

Latest Updates to this Instructable as of 2/28/2016:

1. Major Update.... We can not thank all of you enough as to your many comments, support and help/advice you've given to others here as to the 2BEIGH3!. We released this three years ago and in that time the technology has grown so much we want to take a sec and provide a short update.

With the release of the 2BEIGH3, we were able to start off with a machine unlike any at that time. One that would allow us unfettered control of the 3D Printer portion of the design. In doing so, we were, and still do, operate a similar 3DP configuration in our development of new polymers for 3D Printing. This has allowed us to bring more unique materials to 3D Printing, especially in the area of utility. If you visit our site today, you'll see an array of materials from Nylons to Co-Polyesters that are developed specifically for 3DP. All of these materials have gone through testing on a system exactly like the 2BEIGH3 or similar to it. We were never limited by special boards/controllers, thermal requirements, speed requirements, force requirements or anything that was, at that time, part of the few units available for 3DP. We also want to thank those that went before us in the design of CNC units that utilize pipe in their structure. After months of evaluation, these were the design types that inspired us on the CNC portion. While this unit was built using 2" pipe, we've heard from others that have built larger units with 4" pipe. Again proving the pipe design is still valid for low cost CNC. One of the main goals three years ago was to minimize price/cost. With the advent of low cost hot ends and extruders, now available, one would probably be better off going with one of the low cost CNC units now available and simply adding an extruder and hot end. Reduced complexity and ability to handle 1.75mm for 3DP would be initial benefits. Today you can purchase linear rails of several types at lower prices for CNC or 3DP units. We still suggest the 1/4 20 threaded rod for CNC as it's very powerful. We still use MACH3 as it works well for both CNC and 3DP. We have upgraded our thermal controller to our own design and may release it next year.

We wish all DIY Instructable users and others the best and again thank everyone for their support and great comments. Given the changes in the last three years, we believe the future is going to be impressive!

Our motto..."Give em the knowledge, Give em the tools, Give em the materials and get out of their way"



2. There is a full 2BEIGH3 update here, along with a source for Nylon 3D Printing material here.

3. If you have a new 3D Printing material, there is a Safety Test Procedure for any new and previously untested material here.

As a sample of the unique new properties of just one of these new materials, Here is a 3D Print of a Childs NYLON Prosthetic Insole on the 2BEIGH3 3D Printer.


With the 3D Printer configuration of the 2BEIGH3, you will be able to print parts that meet much higher standards for strength, flexibility and pliability. You will be able to design parts that can take 100's of severe strikes from a sledge hammer and still have a soft velvet like texture.
You will be able to print parts that are almost equal to Factory Die Extrusions. And in some cases, parts that can not be Die extruded due to complexity. The term "delamination" will cease to be a concern.
Nylon and it's derivative polymers have some great features that can be modified with fill density and layer height. Imagine being able to print a permanent coffee filter, bearings that need no lubrication, pliable IPhone cases, extremely tough bands that are so flexible you can tie them in a knot and they'll still support 200lbs!

My hope is that people use this guide to bring their designs and projects to tangible parts and objects as paper and CAD designs are great, but unproven, till built.
My goal for this guide is to take the mystery out of both CNC and 3D printing in such a way as to eliminate that….”its all to overwhelming” feeling or thought.
Because there are several other specific machine designs out there, both CNC and 3D Printer, please refer to this machine as the "2BEIGH3" or "2 by 3" as I will within this guide.

Step 1: Goals and Approach

As I read through the 2D and 3D blogs and sites, it’s obvious that people with 2D want a 3D and people with a 3D want to try and convert it to a 2D.  They are both limited because their machines were meant for a specific action.  While CNC machines work with large X-Y lateral forces (cutting bits) they are very powerful but move very slow and 3D printers have almost no lateral force requirement (other than the platform) and move very fast.  Because neither machine needs a fast “Z” axis, the 2BEIGH3 is designed to allow you to swap out the X-Y sections, recalibrate and back to cutting or printing in less than an hour.  Actually, my 2BEIGH3 takes 15 min including calibration.
The process is going to be that we build a machine, to make a better machine to then build a slightly different machine.  And while that seems complicated, it’s mostly nuts and bolts.  I will try to specifically show you how to create or build the parts you need and where appropriate, provide detailed drawings and CAD files.
You’ll see that I have borrowed some ideas from others here on the Instructables web site, and if I forget to mention an already published detail, please let me know and I’ll update.
So before we get started, what exactly does a 2BEIGH3 look like?

Step 2: Base Structure Reference

As you can see the 2BEIGH3 starts out as a scaled up version of Tom McWire’s “Easy to Build Desk Top 3 Axis CNC Milling Machine”.  When I saw this design, I knew it was what I was looking for because I could “scale” it up.  I think Tom did a great job in showing us a easy frame for CNCs.

Step 3: 2BEIGH3 Specs

So before we get started, just what will we end up with..?

The 2BEIGH3 specs as detailed:

Spec   CNC                                                              3D Printer

Build volume  14” x 14” x 6”                                     14” x 14” x 12”
   355mm x 355mm x 160mm                                   355mm x 355mm x 355mm

Material  Aluminium                                                 3mm or 0.125" ABS and PLA Plastic Rod or Line
               Plastics                                                       2-3mm(or 0.125") Nylon, Nylon Polymers, Nylon 6 and 6/6 - 6' Rod
               Foam                                                            3mm or 0.125" PET (Plastic from water bottles)
(Steel with the addition of cooling)          
X-Y Resolution +/- 0.005                                            ~ +/- 0.012
Z Resolution  +/- 0.005                                               +/- 0.005
(Not bad, but you probably shouldn’t mill pistons for your HEMI or print contact lenses)

Cut/Print Speed 350mm/min                                       24mm/s
   Cutting Foam                                                            ABS

Tools/Tips  0.125” – 0.250”                                           .32mm - .62mm

Software  Any CAD that                                                  Any 3D CAD that
   Makes “.dxf”                                                                  Exports “.stl”
   MACH3                                                                         MACH3
   LazyCam                                                                       slic3r  rev 6

PC    Win XP                                                                    Win XP

I/O   Computer must have a 25 pin +5 volt
“LPT” printer port.

Power Usage

  Power usage with stepper motors is difficult to predict as stepper motors use most of their power the opposite of say, fan motors.  They are rated in "Holding Torque" and this means "at a stand still they will not slip".  So, they actually draw less power moving the tables, then when they are not moving.  To hold the 3 used for the CNC, Hi or Lo res, the power is about 140 watts for the motors, drivers and control board.  That would drop some as the X and Y tables move.  We wouldn't expect the Z axis to move much at all.
  With the 3D Printer configuration, we will need to add 55 watts for the Hot-End as it is powered during the entire print.  We will also need to add some power for the extruder, but as I mentioned, it draws less because it is always working.  A lot less, in the range of 15-25 watts.  So for a 3D Printer configuration, we could get over 220 watts.

Step 4: 2BEIGH3 Initial BOM

    Before I detail the BOM, I should explain my approach.  Like you, I wanted the most for my money.  And while it would have been easier to throw cash at parts (if I had cash) like bearings, special threaded rods, hot-ends and extruders, these parts would have also locked us into a machine that would be difficult to scale up or get replacements parts later on.  It would also be difficult to hack the 2BEIGH3 for your purposes if there were proprietary components.  I have already hacked my own design as I want others to take what they want/need from the design.
In theory you should be able to scale a 2BEIGH3 up to cut 48” x 48” x 24” foam CNC or print a 24” x 24” x 24” block of plastic just by changing the pipe, threaded rod and timing belt lengths.  I therefore took the approach that everything should be a commodity or a modified part.    We'll consider Stepper motors, controllers and drivers to be a commodity for this build.  Linear bearings are a commodity, but way to expensive. 3D printer hot-ends and extruders are not yet a commodity, and therefore we’ll be building those.  I also wanted to keep the total shipping costs down, so everything (other than standard hardware you can get at any HW store) is available from just 4 vendors.  I will mention but not detail small screws.  I kept all screws and bolts to ¼ 20 (6mm) and all small screws to 6/32 (4mm).

Basic Machine
– The BOM describes a machine with a 28” width, 26” depth, 20” height with a ~16” Z axis neck.  Again, if you want a different size machine, just scale up or down.

CNC BOM
Let’s get those things on order that we need so they’ll be on-hand when it’s time to install them

4 each NEMA #23 stepper motors  5-8 kg-cm with 6mm (0.250”) shaft
Shop around….there are several places to buy these.
I used http://www.circuitspecialists.com/
1 each 4 axis stepper controller – connects to computer LPT port. (NOT USB).
I got one from http://www.cncgeeker.com/

4 each stepper driver boards that will connect to the controller card and motors.
Note:  I suggest a vendor that sells a 4 axis kit that’s known to work together.
Ratings should be 3 amps, 12-24+ volts 1-2-8-16 step similar to the one I bought.
Note2: The 3D printer will reuse the X and Y stepper motor but it also requires a 4th stepper for the extruder, thus a “4 axis controller/driver” is required.

Power Supply for Steppers – The controllers plus driver usually takes two voltages.
7-9 volts and 12-24+ volts
For the 7-9 volts, any 1 amps regulated PS will do….an old regulated wall wart should be fine.
For the 12-24+, I suggest a regulated 12 volt @ 10-12 amps as you’ll not need more voltage with most NEMA 23  and anything higher will make the motors run hotter than required.  As 10-12 amp power supplies are not everywhere, I had several 12 volt 4 - 6 amp wall warts about, and my driver boards are individual boards, so I put a wart on each board and connect all the grounds  (-) together.  Note: do not parallel these PS as they are switchers and will become erratic.  Just connect the grounds together….(-)…not the (+)

Mach3 CNC Software by Artsoft Inc Please Purchase
LazyCAM CNC Software by Artsoft Inc - Free
Mach3 SW runs on the computer connected to the Stepper Board.  It converts GCode from the CAM and Slicer programs and drives the signals to the Stepper Motors.

Now for the first trip to the Hardware store!
Pipe  - all are Standard 1” iron pipe.  You can buy pieces or like me, I handed the Hardware store guy a list and had him cut and thread.  Saved about $20 this way. Again, if you want to scale up, now is the time to go to 1 1/2" or longer pipes.

QTY   Desc
2 each  24”
3 each  elbow
1 each  Tee
1 each  Flange – note…..these are made outta gold..!
3 each   Unions
5 each  6”
2 each   12”
2 each   end caps

Step 5: Frame Assembly

Refer to the 2BEIGH3 frame drawing to determine what piece goes where.
Assembly
   The goal here is tight..tight...tight.  This is why I’ve used unions.  As an elbow or Tee will never ever line up where you need it, the unions are here so you can tighten the pieces as tight as possible and then use the unions to align for the right angles.  This is why they make tape and other sealing compounds, because they know that you’ll always have to compromise tight for alignment.  I do not use Teflon tape, just two large wrenches and muscle.  When complete, you should be able to flick the flange with a finger nail and feel it with your finger at either end cap. 
Tight
  As for alignment, at this point, you only need to make sure the Z axis neck is at a right angle to the rest of the frame.  There are several ways to do this.  I had an accurate digital level.  I set the two legs on 2x4 so as not to set on the end caps and used a shim to level the legs for a reference.  Then I measured how level the 12” piece connected to the flange was and adjusted the two outer unions to correct.  Remember, the Z Axis only needs to be level with the legs not the earth. The Z-axis union is just for rotational needs and you only need to get reasonably close.
Now, look at your frame…all your future efforts and work will take place between the two 24” pieces and about 8” up form that center.  Now is a good time to build, buy or invent a solid table to support a 2BEIGH3.  I’m tall, so my table is 48” off the floor.  Also, iron is not light.  A complete unit can weight 50 lbs +.  This is a good time to mention noise.  The CNC version will use a high speed mini router that is very loud as it cuts.  You must wear ear protection. Period.  The 3D printer makes almost no noise, but hot plastics stink and emit fumes, so you’ll want to vent all other odors and fumes. 

NOTE: 3D Printing with these plastics is just like cooking on an open stove.
    Never let things get to hot.
    Vent all odors and fumes.
    Don't touch the electricity.
NOTE II:  Polycarbonate can become unstable at very high temperatures.
    There will be a separate instructable for 3 D Printing polycarbonate and it will describe a PWM controlled heater for the Hot-End. The PWM controller will have a top limit for temperature.   Please do not try to print Polycarbonate with the released design.  Polycarbonate can change state from a plastic to a crystal foam that easily catches on fire if the hot-end temperature exceeds 400C.  Well above printing temperatures.
  Because these fumes emanate from the hot-end's thermoplast area (About the size of a pencil eraser) the actual amount of fumes is quite small.  Something along the line of a standard cooking stove vent is sufficient as long as it's in a position above the hot-end to capture odors and fumes.

Installation
Now is a good time to plan your installation.  My wife and kids voted the garage! One last item on the frame.  While it may be in the garage, you may want to show your friends.  Now is the time to paint the frame.  As it’s iron and will rust, use paint with a rust inhibitor.  You’ll notice mine is not painted…!

Step 6: Tools Needed for the Initial 2BEIGH3 CNC Section

Gather our tools and get organized!

Pipe wrenches
Pliers
Screwdrivers
Taps as we are going to tap a few holes
¼ 20 and ¼ 28
The ¼ 28 will be used later for the 3D P but might as well get it now.
A tap Handle as we will hand tap three holes
We will use a hand drill to tap remaining holes.
Small Bench Drill press – nothing special, just a small bench drill press.  You may even be able to rent/borrow one as we won’t need it very often.  We will need this to drill the holes for the 3D Printer hot-end and will be drilling a ¼” hole 1” deep in aluminum.
Hammer
Punch to mark holes to be drilled
Hand Drill – reversible and variable speed
Hardened Drill bits – ¼, 1/8, 7/32 and 9/64 - For all 1/4-20 threaded holes, drill at 7/32" and tap to 1/4-20
   There will be one hole on the hot-end that is drilled at 7/32, but tapped at 1/4-28.
Eye Protection - goggles
Ear Protection – ear covers or plugs
Hairnet if needed
Hack Saw or 28” bolt cutter
TIP: I quit cutting small metal pieces years ago and just use a bolt cutter.
Sandpaper – carbide for smoothing metal edges
Volt Meter/DVM – Harbor Freight has these for ~$5, however, for the 3D Printer, we’ll need one that measures temperature from a thermocouple.  Harbor Freight has those including the thermocouple for about $20.00

Step 7: 2BEIGH3 Safety

The 2BEIGH3 uses dangerous extremes to do its job.
I am in no way responsible for any injuries from assembly or usage of the 2BEIGH3.
1. Use caution with all power tools and wear appropriate eye, ear and hairnet gear.
2. While you will be printing at 265c, the hot end circuit can drive to 320C..It will not just burn you, but mark you for life.
3. If not connected correctly, the hot-end can reach 1400F!
4. The Stepper motors connected to the 1/4 20 threaded rod allows the CNC X-Y table to push steel past your cutting bit.
     It can crush your finger if you are not careful.
5. As noted earlier, you must vent fumes and odors.

A word of note:  I designed and built this unit in 8 weeks from concept to cutting/printing parts.  Now that I have them, I can tell you it was not the overwhelming task I thought it would be at all.  Just have a bit of faith in yourself and like they say "Just do it". Yes, I made mistakes along the way and I threw em in a "Don't do that again bucket".  And "yes" my CNC bit tried to drill its way to China, however, Plastic is cheap and disposable.  Knowledge is not!
  During my design I studied lots of posts here and on other sites.  They were so helpful that I have decided to pay back the 2D/3D community by documenting my design.  My thanks to everyone that took the time and effort to share their designs.

The 2BEIGH3 is Open Source Hardware.  I encourage people to take ideas and hack it.  Please refer to it as a "2BEIGH3" or "2by3" so others don't confuse it with already available kits or complete units.
In addition, the 2BEIGH3 3D Printer has a hot-end designed for NYLON.  You will be amazed at how you can now print objects that are extremely slippery, bendable, fold-able, tough, durable, semi-transparent and chemically resistant to solvents. Yes, you can print hose, but you can also print soft durable keypad covers, flexible overlays and a zillion other parts that are difficult in ABS.

NOTE Of Caution to existing 3D Printer Owners about NYLON:
NYLON heats differently than ABS.  Please see the attached NYLON properties PDF.  Simply inserting NYLON into a REPRAP, TOM, UP or other 3D Unit, will probably damage the unit in some way.  I have a friend that had to order a complete new hot-end as he didn't heed my warnings.
And "yes" "weed-wacker" / "trimmer line" is made of NYLON.....it's also made of fiberglass and other bits and pieces of nasty things. Put it into the 2BEIGH3,  REPRAP, TOM, UP or other 3D Unit, and you'll hear the sound of french fries being cooked....that's the tip being coated in goo.  Burnt fiberglass has to be drilled out (as my friend found out).
In addition, NYLON is extremely slippery and unless you have a "Spiky" extruder, as http://www.thingiverse.com/thing:21782 your extruder will more than likely slip.  All Nylon polymers require high pressure extrusion.

0.125 - 1/8 NYLON rods for the 2BEIGH3 are available from McMaster Carr (8538K12)they come in 4' sections, are low cost ~$1.68 are round and will print a lot of small parts. In a few months or sooner, Nylon material specifically for 3D Printing will be available here. and anyone can signup here.

I get the white rod and take a rag and coat the rod with just a bit of old printer refill ink for the color I want.  Nylon absorbs water/liquids at a greater level than ABS, so the color looks a bit translucent depending on thickness of the part.
3mm ABS is available from several vendors on the web, just do a search on 3mm ABS spool.
Again, 3D Printing is no different than cooking on an open Stove.....So..
Don't touch the Hot Parts..
Vent the Odors and fumes..I have uploaded the "Dupont Nylon OSHA Handling and Ventilation Guide.pdf" for those interested or desire guidance.
Don't touch the electricity..

Step 8: Basic 2BEIGH3 CNC X Y Table BOM

Basic 2BEIGH3 CNC X Y Table
We will need to make some parts for our precision CNC table, and to do that, we will make a simplified lower precision table to make those parts.  This will be made out of some drawer slides, aluminium “U” channel and some 12” square boards. 
This is similar to https://www.instructables.com/id/Building-a-drawer-slide-CNC-machine-for-under-200/
I chose this route rather than to just say…”Here is the dwg, just go get them laser cut” for two reasons.  First, the lower precision table will be good enough to make the parts needed for the 3D Printer X and Y table, and 2nd, some people may not need/want 0.005” precision
Again, this is a lower precision X-Y axis table, so we are looking for "close" not exact.   As you build this table and you see you need to add a spacer (couple of washers), move a hole slightly or add a temporary "C" Clamp....just do it.  The most important part, is actually the NUT for the threaded rod and we're going to make a one that will be easy and solid....no slop.  I will provide CAD drawings for the precision table in another step.  The drawer slides have too much lateral tolerance for a precision table, but are fine for making a lot of parts that don't require +/-0.005  We can make both the precision table parts for the CNC table  as well as the 3D Printer table parts with a quick and simple table. 

BOM

QTY   Desc
HW Store-
2 each  16” – 20” Ball Bearing drawer slides – These come in a pair =
4 total
1 each    16” – 20” Centre Drawer slide. Single part
2 each   ¾ “ X 36” Aluminium U Channel
2 each    Boards/wood 12” x 12” x ~1”
3 each    ¼” 20 x 36” Threaded Rod
   These need to be straight.  I went to 2 HW stores
   And looked at ~ 100 to pick 3
   To test if it’s straight, just roll it on the store floor
1 each   1” x 1/8” x 36”flat stock galvanized steel
2 each    2” “L” brackets
1 each    Aluminium “L” channel ½” x ¼” x 36”
2 each   Boards 6” x ~18” x ½”
   These are for the Z Axis – try to get clean straight boards.

Order
1 each   1” x 1” x 12” Delrin Plastic
   McMaster Carr PN 8739K92
   50% for the CNC and 50% for the 3D Printer
3 each   ¼” couplers McMaster Carr 6412K11
1 each    Electric Cutout Tool   Harbor Freight has these for ~$20
   This is the business end of your CNC
   If you already have a similar tool with a 1/8" collet, that will work as well
   It’s the next item that counts!
1 each    Three Flute Coated Carbide End Mill 1/8"
   McMaster Carr PN 8927A531 $19.00 but worth every cent!
   This “will” cut HEMI pistons!
   This is where you don’t go cheap.
   No matter what you cut, from cardboard to steel.

Step 9: Getting Those Stepper Motors Running

So, those stepper motors and controllers should have arrived by now!
No reason to go further till we can move motors!

Gather parts:
Computer with 5 volt Printer port-
Load/Install MACH3 SW
Load install LazyCAM SW
Stepper motors
Stepper control and driver boards
Power supplies

MACH3
This SW talks to the printer port with pulses that tell the stepper electronics what direction and how far to rotate the motors.  It has an excellent and proven track record in the CNC world.  It also has a lot of variable/settings that can take a while to learn.  Rather than post a tutorial on MACH3, please go to the Artsoft Web site as there as several great videos on setup for Mach3 and LazyCAM
To move you along, I will include my control file as it already has settings for the machine we’re building.

Steps for MACH3
1. Install MACH3 you should have rebooted after install as required.
2. Leave the stepper controller and motors off and disconnected for now
3. Open/run MACH3 and then simply close it
4. Download my Mach3Mill.xml file
5. Make a backup of your existing Mach3Mill.xml file
6. Copy the downloaded file over your existing Mach3Mill.xml located in the “C:\ Mach3 Directory
7. Reboot
8. Run Mach3
9. If the reset button blinks, clk it
10. Go to Config/Ports-Pins/motor output and see the setting noted.
11. The DIR Low active and Step low active are the 2 items that may be different on your controller from mine.  When we get to the motors, and they don’t turn, these are the settings to click/change.
12. My XML file is set for the ¼ 20 rods with a step division of 8
13. I have attached a simple part in gcode for the 3D Printer.
14. Download it and within MACH3 load it.  You may need to change the extension, but M3 will read it. 
15. You should see the part in the small graphic window.
16. Clk the ZERO X, ZERO Y, ZERO Z, ZERO 4 buttons
17. Clk the green Cycle start and the SW starts the process.
18. You’ll see the progress in the small upper right window, but it is slow as the machine must cut slow.
19. For visual effect, just keep clicking the FEED RATE + arrow to speed it up.
Not for actual part cutting!

Motors and Drivers
1. Hook up the motors to the driver boards first using the supplied board and motor documentation.
NOTE: Do not power the driver boards without a motor connected or they’ll be damaged.
2. Use a few buss bars to keep track of grounds and power.
3. Use an outlet strip with a switch to turn on the power supplies.
4. NOTE: Don’t assume anything on power supply polarities.  Use the meter to measure and mark polarities.
5. Hook up the 7-9 volts to all boards as needed.
The 7-9 volts is just the low level circuitry power supply and draws less than an amp.  Careful, a +5 volt power supply won’t work.
6. Hook up the 12 volt PS – Again, if you don’t have a single supply, then connect the grounds together of four supplies, but the + terminal only goes to a single driver board when there are individual boards.  If you have a single board with all 4 axis, then you must use a single 12 volt 10+ amp power supply
some people use a old power supply from a computer.  Do a search on this site for examples.
7. Connect a fully populated 25 pin printer cable from the computer to the control board.
8. Connect the interface cable from the control board to the four driver boards if you have individual boards.
9. With MACH3 running, turn on power.
10. The motors should lock/click.
11. You should NOT be able to turn the shaft with your fingers.
12. Place a sticky note paper on each shaft. (so you’ll see them turn)
13. Use the left, right, up, down arrow keys on the comp keyboard to rotate the X and Y motors
14. Use the page up and page down to rotate the Z motor
15. Use the numeric keypad + and – to rotate the 4th motor
16. If the 4th motor does not respond, go to config/system hotkeys and A/U++ to make the + key + and A/U—to make the – key reverse.
17. Again, if the motors do not move, you may need to click and change the signal polarity (direction) as noted above.

With motors running, you’ve won the biggest CNC/3D Printer battle
   This is the part that stops most people from building a CNC machine or Printer.  Take your time and check your work before turning power “ON”.  Believe me, it all gets easier from here!  Even the 3D Printer is easier than this initial step.
In the photo, you'll see a roundish grey unit with a knob on top.  This is an Auto-transformer that I use to vary speed of the cutting tool.  You will need to reduce the speed of the cutter to cut plastic, but we'll use a light dimmer as we only need ~55volts at the cutter for plastic.

Step 10: Precision CNC Table

  Take a look at the CAD Drawing image and the photo's to get an idea of our Precision CNC Table.  It looks like a lot of parts, but there are 10 "Y" braces that are all identical.
For the X Axis, the table will use 3/8 steel rod and travels along the rod with a captured bearing.
This keeps our cost down as linear bearings are extremely expensive and we'll need several. This bearing is at any HW store as it's used for patio door rollers.  ~ $5.00 a pair.
The Y Axis uses the same bearings, but on 3/4 square aluminum tubing as the Y table will move almost completely to either side of the X Axis.  We will brace the X Axis as it's hard to believe how much a 3/8 " rod will bend in just 28".!
The material is 0.220 Plexiglass or extruded acrylic that you can get at the big HW stores.  Its tough stuff as used in the horizontal plane on this project.
NOTE:  To cut the largest part for this on the lower precision table, you must make sure your low res table can cut a 12" x 12" part. 

   You DO NOT cut the outline.....Just have the HW store guy cut you a 12" x 12" piece.  Lowes sells 18" x 24" x .22"  I have them cut 2 pc's 12 x 12 and give me the rest for me to cut smaller parts from.
The drawing shows a cut plastic part for the threaded rod nut, this has been changed to a small block of delrin drilled and tapped to 1/4 20 for a much better fit and easier assembly.
The 12" x 12" x 2" block of wood on top of the table is so we can mount our material easily and in different locations to cut without scaring our nice clear plexiglass.
If you look you can see where my bit went a bit lower than I planned on a part or two!
Parts are connected via a TEE and SLOT that we'll cut in the plastics.  This makes for a very strong right angle mechanical connection of the parts.  All assembly screws are 1/4 20 1" Philips The screws used for the roller bearings are the same for the X Axis, but 2" for the Y axis.  You'll need twice as many nuts and washers as some screws get more than one of each.  I don't count these out as you may not want all the bearings.  My 2BEIGH3 only uses 8 for X and 8 for Y, but my design denotes 22 for maximum precision.

Step 11: 2BEIGH3 Precision CNC Table BOM and Assembly

The fist image shows the exploded view for your reference.  Again, as we have already cut our plastic, it' simply a matter of screws and nuts.

Bom

QTY         Desc
2 each     3/8 DIA. X 36” steel rods – Stainless
2 each     ¾” x 36” square Aluminium Tubing
16 – 22   Patio Door Slide Bearings
BOX       100 pc’s of 1” ¼ 20 Phlips screws
2 BOX    100 pc’s of ¼ 20 nuts and washers – Stainless
1 each    “T” Nut for ¼ 20
1             YPlate
1             XPlate
10           Y Struts
1             Y Stepper Mount
2             Y TNUT Plates


Assembly per the drawing is straight forward. 
4 Items of note:
1. The "T" nut you get from the hardware store must have 2-3 small holes to mount in the the plastic Y strut.
    You may need to drill and use a slightly smaller screw than a 6/32 for the T nut.   Either way, it's plastic and you need to drill slooowly as to not chip the plastic.  Once assembled, this is strong, but getting there requires a bit of care on mounting the T nut.

NOTE: I have updated both the X axis and Y axis Threaded rod nuts based on excellent user suggestions.  The material is Delrin and the last 2 photos denote the dim's.  These are a breeze to drill and tap. They go a long way to decrease backlash and increase precision.  My thanks to all of the users contributions.

2. The only spacing issue, is that you need to make sure the bearings for the Y axis are all spaced the same,  yet long enough to allow the Y plate to clear the top of the Y stepper motor.  So from the bottom of the Y Plate to the center of the bearing curvature, it should be about 34mm.
3. The drawing shows the square tubes at about 15".....to make the drawing easier....They are actually, 36" cut to about the max depth of my table or 28"
4. The Y axis threaded rod will need to be reduced in length.  I waited till I set the table on the frame, measured and cut the Y axis threaded rod about 3" from the frame neck.

Next
Connection of Table to Frame - Assemble the complete table except X Axis threaded rod and stepper motor.
Set the table on the frame.
Drop a nut on a string down from your estimate of where the router bit will be...about 3" out from the flange.
Align the X plate with the Y plate.
Center the table where the nut denotes the location of the router bit.
Install the X axis threaded rod and stepper motor connecting them with the coupler ordered earlier.
Shim the stepper up so the threaded rod is parallel with the 3/8" steel rods.
Clamp the 3/8" rods to the right leg of the table and center the stepper motor.
Turn on the stepper system and while holding the stepper motor, let it pull the table to the right side leaving about 1-2" of clearance.  Be careful as you do this.  The table should not move very fast at all.
Once the table is to the right side of the frame, you're at your mechanical reference point.
You should now mark and drill a 0.250 " hole in the end of the 3/8 " rods and having marked the location on the pipe, drilled a through hole at three of the four intersections.  Right close, right far, left far.....not left close.
You should now add 1/4-20 " 2" - 21/2 " bolts to secure the table to the frame.
Mark and drill holes in the two "L" brackets to mount the stepper to the pipe.
Use your arrow keys on your keyboard to make sure the tables move as designed.
Note: Be careful moving the Y axis toward you so as not to have it's "T" nut reach the stepper coupler.
Remember, you have not installed any limit switches yet, so there is NO limit!
You should lightly lube both threaded rods with a non drying lube.  Something with PTFE/Teflon in it works well.
NOTE:
Do not get caught up in trying to make everything line up perfectly.   It doesn't matter...The X and Y are aligned within the assembly and the Z has no X or Y....Just up and down.  You could mount the table off by 20 degrees in the horizontal plane and it wouldn't matter.  What's important is that when we tell the X axis to move 20 mm, "that" it moves 20 mm.....no more, no less and that's done in calibration and my XML file is already set up for this design mechanics. But we'll check to be sure.

Step 12: 2BEIGH3 Z Axis for All Configurations

"Z"
The 2BEIGH3 Z Axis uses one "center drawer slide".  They are rated at 100+ lbs, so they're very good for this purpose.
They are great in the X and Y axis, but we'll want to shim them for 45 degree angles as they do give a bit at 45.
NOTE, you do not need to shim the Z Axis if you're not building the precision CNC.
The Z Axis is basically two boards connected to the drawer slide.  The Stepper motor is literally wood screwed into one of the top corners (for now).  We will cut a piece of the delrin and tap it as out threaded rod nut.
With the Basic table operational, we will build/cut a more secure bracket for the Z Stepper motor.
For the CNC, this axis has to support the weight of your router, dremel, or other cutting device.
For the 3D printer, it supports the hot end only as the extruder is mounted off the frame.
As with the drawer slides on the basic CNC table, use small screws to make sure the head of the screw does not block the travel of the slide.
To mount your dremel, or router, I used plain old metal strapping, some wood screws and a strip of rubber under the strapping to reduce vibration.  Again, once the basic table is operational, you can cut a better, more accurate mounting bracket.
The Z Axis threaded rod nut is made out of the delrin you bought.  Simply cut and drill to the drawing (in mm's).
Then use your 1/4 - 20 tap and tap the lone hole for the threaded rod.

A word on the attached photos.  Don't let all those wires scare you.  I have simply added some 12 volt fans to keep every motor cool.
Here's the list of wires/cables:
X motor
Y motor
Z motor
Extruder motor
X fan
Y fan
Z fan
Extruder fan
Thermocouple
Power to hot-end or cutting router
 See..!  Pretty simple stuff, but it's scattered, to where the motors are and looks complicated!

Step 13: Thoughts on CNC

     As I mentioned, until I started this project, I knew nothing of setting up a CNC.
I've learned that it's much less complicated than it looks hardware wise.
The Software assumes you have some mechanical CAD/Drawing knowledge, and let's face it, if you're building the 2BEIGH3, you should have some CAD training.  I suppose you could just dl designs from the web and build those, but.....you're an inventor....right?....

Important tips/notes/lessons/points:
1. Frame is to be "tight"
2. Carbide bit.....sounds like overkill.....it's not.....you'll see when you get it...it can cut you just holding it!
3. Calibration.  that's distance in mm's or inches.  NOT where X and Y stops or limit switches are.
4. Watch ALL of the Artsoft videos.......twice!
5. Don't complicate any assembly.
6. Getting the stepper motors running with Mach3  is your biggest hurdle. And it's not really that tough.
7. When your friends find out you have your own CNC......be prepared to be asked to cut all kinds of stuff!
8. Once I got the basic table running, I made all kinds of little improvements, fan holders/frames, stepper motor bracket for the Z axis, etc.  You will too.
9. Don't look back.....we got that 3D printer next...!

Step 14: 2BEIGH3 3D Printer Overview

Overview
  We consider CNC machining to be "subtractive manufacturing" or "subtractive build" method.  We start out with a bar or slab of material and cut off what we don't need, tossing the remains away. While you can make 3D like objects, there are still limitations.  There will be scrap on the floor as unusable material.
     The 3D Printer is "Additive Manufacturing" as we take a constant source of material and force it to a desired shape.  Nothing is wasted.
The 2BEIGH3 3D Printer uses the same operational principles as most other current X-Y plastic extrusion printers.  Again, the main goal was for a combination machine that could quickly be configured for CNC - 3D - CNC.
   A major benefit of the 2BEIGH3 is that the hot-end ( the component that heats the plastic) and extruder (the mechanism that pushes the plastics rods into the hot-end)  are designed for more than just ABS or PLA.  They are also designed for NYLON and other polymers.   NYLON has a ton of features I want everyone to experiment with in the design of new parts that can take advantage of it's properties.  I have provided an MSDS for NYLON for those interested.
    There are of course differences in how we print with NYLON as opposed to ABS.  One of the main differences, is that we will "melt" ABS, PLA and PET but we will "cold extrude" Nylon, Nylon polymers, Acrylic and polycarbonate.  Of course, the Tighter polymers like Nylon are not really cold, but they are not melted either.  And this is where the high "pushing power or compression capability" of my extruder is required.   This is also why retraction isn't advised as the pressure is large enough to make it difficult to completely relieve by simply pulling the material back.   
When you learn how to print with NYLON, I am sure you'll be pleased with the final results.
And I'm sure you'll find, like I did, that the major key to parts printed in Nylon and Nylon polymers is that it's tight bonding literally eliminates "de-lamination"!
Going just a bit deeper at this point....We can control the "density" of the internal fill of printed parts from within the software.   NYLON is very pliable as you know, so we can literally change the hardness/firmness/tensil strength of a part by changing it's fill percentage. Want a small keyboard button overlay for a control box.....fill at 25%....want a bearing that has a bit of give to reduce vibration.....fill at 50%...want a hard almost UN-bendable lever....fill at 100% and so on.

    For those familiar with 3D printers, here are some differences when printing with NYLON.
I'm sure you folks can teach me a lot more about 3D printing and I appreciate your comments.

Nylon welds to Kapton. (Kapton tape is a super high temperature rated tape for heating appliances.)
The tiny threads left behind can not be removed with acetone as NYLON laughs at acetone.
I hit the part with a propane torch for about .3 sec to burn the threads.
NYLON will absorb water, so keep it dry when not in use or it will add blemishes to your prints.
If your hot-end isn't mechanically tight, the NYLON will find a place to leak out.....makes a mess.
NYLON strands from printing are not a fire hazard.
Nothing glues to NYLON except other melted NYLON so if you need multi-part assemblies, they should be designed to be held together with hardware.

NOTE: Some of the photos of the Child's Insole are very high resolution.



   As noted in the previous videos, the flexibility and pliability of parts made with Nylon and similar polymers opens up a whole new group of possible parts and their usage.
   It's also important to point out that one of the major complaints of parts printed in ABS and PLA, is lack of strength or mechanical structure.  Even today, some kits come with instructions to have the end user print a series of replacement parts for the 3D Printer they've just purchased.
   The very nature of 3D printed parts means that all parts rely on the attachment of each individual layer to the last layer. 
   One of the major benefits of printing with tighter polymers like Nylon and it's chemical relatives, is the extremely tight bond from one layer to the next.  In reality, while these parts may look similar to parts printed in ABS or PLA, their mechanical strength and structure is, in some cases, almost that of a Die Extruded part.
  So those currently building a 2BEIGH3 can see the strength of their future parts, I am posting the next video.
This is a preliminary video made by one of the technicians as the samples I've submitted are not scheduled to go through full test for another month.   The technician sent me three short videos, two each at 320 frames/sec and one 180 frames/sec.  In these videos a sample of polymer 618 (my part number) is struck by an 8lb sledge hammer.
For those of you that will want to build tough parts, you'll want to take a min to watch.



Even if you're not ready to build a 2BEIGH3 just yet, please take a moment to watch the videos.

   With the excellent input from others that have contributed to blogs, postings here on instructables, comment sections and product reviews all over the web, It is my hope that you find the 3D Printer configuration of a 2BEIGH3, helps us all to put the
"Disruptive" back into a "Disruptive Technology".

Step 15: 2BEIGH3 3D Printer X and Y Table

The 2BEIGH3 3D Printer X-Y Table is a fast belt driven table that does not use linear bearings, but instead depends on gravity as we don't expect the table to operate upside down.  This is not meant to be funny, as some printers "can" work at a 90 degree angle.
Rather than linear bearings we will use delrin pieces that will slide easily along the 3/8" steel rods.  We will also use the delrin pieces to level the Y platform as that is one of the more important 3D printer requirements.
We will reuse the X and Y stepper motors from the CNC table as we have couplers that allow a quick change out from one table to the other.  I cheat here and actually bought 2 additional stepper motors to reduce my change-over time.
The X Azis stepper does most of the hard work here as it must push the complete Y axis along with it's motor left an right.
One change I would make would be to use a NEMA 17 or 11 for the Y Axis to reduce it's weight.  This is what is holding my resolution back for the moment.  I can slow the unit down with ABS and it's fine, but we can loose control of the NYLON at to slow a speed as it will start to fold over (Fancy term for "drip") due to it's viscosity.
  To clamp the belts to the tables, we will use 2 pieces of the 1" x 1" delrin.  One tapped for a 1/4 20 and the other for a 1/4 thru hole. take a look at the drawings and pdf for dimention data.  You will need to locate the hole for the clamp in the center of your tables, but again, it's better to build the tables up and then lay a belt across the two sprockets to best locate the position of the clamp hole.

  For Mach3, close the program and copy your existing XML file to a safe place in case power goes out.
You need to do this because Mach3 dosn't update it's xml file till you close the program.  Until then, your changes are in memory and not the xml file.
DL my next XML file as it's configured for 3D printing.  Again, you should only need to change the two settings mentioned earlier on polarity.
My XML file assumes all motors are set as follows:
X and Y = 1/16 step
Z and A(extruder) = 1/8 step



BOM for the HW store
4 each       3/8" x 36 " SS rod
1 each       24" x 24" x 1" MDF Wood
1 each         1” x 1” x 12” Delrin Plastic
                   McMaster Carr PN 8739K92
1 each        24" x 12" x 0.220 Plexiglass - We will hand drill this part
4 each        XL Series timing Sprokets
                   McMaster Carr PN = 57105K14
2 each        63" timing belts
                   McMaster Carr PN =6484K453
Lots of 1/4 - 20 1" screws and 2 each 1/4 - 20x 3" bolts
4 each        Patio door roller bearings
                   NOTE:  This is slightly different than the CAD image as I found that
                   there was not enough weight on the Y Axis to make the delrin bearing work.

BOM from our Basic CNC Cut parts
8 each        Bar Struts
2 each        Transports
2 each         Stepper motor mounts
1 each        Y Axis Base Plate

Assembly:
You'll assemble all of the X axis and just the Y axis table first.
Then set the parts out on your MDF table and mark for holes to drill.  Again, 1/4" holes.
The Y axis delrin bearings sitting on the X axis rods will indicate spacing.  I do this rather than dimensioning a large board, only to force parts into position.  This approach allows for tolerance for all of the individual parts.
After initial X assembly, complete Y axis assembly.
You will note that the 3/8" rods float in the supports at this point.  Tis is just for initial assembly.  After you have the unit assembled, you should use snug fitting wire ties on each side of the supports to secure the 3/8" rod.  Otherwise, they may move out of their location.
The Y axis plate is just a small base plate.  The intent is that you will want some main printing plate on top of this base plate and that you may want a different size than I use.   I use a 12" square of the plexiglass only because I don't currently plan on printing larger parts.  A 14" square is about the limit on a centered table.  Other wise......scale the whole unit up!

Step 16: 2BEIGH3 3D Printer Extruder Assembly

  The purpose of the extruder is to pull the material off of the spool or roll, and push it with force along/through a tube on a path into the hot-end. 

    The 2BEIGH3 3D Printer Extruder Assembly is similar to the geared extruders used on other machines.  I have heard these referred to as a "Wade's" type of extruder.  Please do a search on "Wade Extruder for 3D Printing" and read about the variations and usages.
The major difference in the 2BEIGH3 extruder from other geared units, is that the gear ratio is about 15% larger and the important difference is that the 2BEIGH3 extruder has spikes in the HOBB's screw (the section of the 2" screw that the material comes in contact with)  to grab the Nylon as well as the ABS.  Without spikes, the Nylon is far to slippery and the extruder, will eventually rub a flat spot in the Nylon and stop extruding completely.
The 2BEIGH3 extruder is seen in the photos.  The gears are cut from plexiglass (extruded acrylic).  You will see that a white lithium grease has been added to the teeth to reduce friction as extruded acrylic is not something we want gears made of, but for now it will get us printing.  I will eventually post another instructable to show you how to transition to a printed extruder with NYLON that will not need lubrication.  I'm still using this extruder as it's working great...

Assembly
All screws ( except the hobbed screw and pressure handle pivot) and nuts are 6-32.  The plates are spaced apart by the thickness of a nut.  Just add  screws to the main plate, add  nuts, add the next plates, add a nut, add last plate, add a nut.....kinda like a sandwich.
The small gear is epoxied to the Stepper motor shaft. 
     The stepper shaft is 6mm or .250.  You have cut the gears with the basic CNC table from the CAD prints and I designed the center hole to be tight.  You will need to reem/file it to get a snug fit,   Then use some sandpaper to roughen the shaft surface of the stepper.  Do not epoxie till you have built the assembly and have aligned the gears.  Remember, the material is just 0.220 and we want a much surface area as possible as the gears mesh.
A simple "fast curing two part epoxy" is used.
TIP:  I cut 4 small gears and 2 large gears in the event I needed to break a small gear to reposition it, or large gear during assembly.
The business end of the extruder is that 2" 1/4 -20 Screw.  Between the two "threaded "fender washers", we have used a dremel cutting disk to cut small slots along the opposite axis of the threads.  This gives us the "spikes" we will need to grab and push the NYLON and ABS into the hot end.
The two washers are what's known as "Fender Washers" with a 3/16 ID and 1" OD.  The hole is just right to tap with our 1/4- 20 tap and will turn the washer into a very thin nut!
These two threaded fender washers will be on each side of our ABS rod or line to keep it from bending or moving away from the spikes.
The two delrin plugs - # 1 is the same width as we have between the two threaded washers.  Delrin is just as slippery as Teflon and Nylon, but very hard.  The plug #2 is just a 1" x 1" x 1/4" square that pushes against the first plug.  The handle or lever, is sping loaded and applies force ( a lot) on to plug # 1, in turn plug # 2 in turn pressing the ABS or NYLON rod firmly against the spikes.
The distance between the threaded washers is 0.125 or 3mm+  In the photo you'll see a white tube just above the spikes screw.  I found that the pressure was so great that I needed to guide the ABS and NYLON  directly to the tubing connector.   The tube is a 1/4 OD and 1/8 ID Nylon standoff. The spring is just an available spring at the HW store I tested till I got max pressure without breaking plastic and making it easy to change from Nylon to ABS and back.
The two 626ZZ bearings are the same as the other patio door bearings.  You can either order these online, or just pop them out of the patio roller shell.  Note (in the photo)  the crimp side and this is the side the bearing will pop out on.  I installed a 1/4 20 bolt with a nut on both sides of the bearing.  Placed it in a vice, give it a good pop and out comes the bearing.  These are about $2.00 online.
Once I cut the parts, it only took about 20-30 min to assemble.

The Extruder is connected to the hot-end via a "bowdens" system as seen on some Ultimaker printers.
This is a "Quick Connect Coupler MMC PN 51215K106"
This makes it easy to put the extruder anywhere we want, and to change hot-ends.
The 2BEIGH3 uses hot-ends with the nozzle installed for different resolutions.
My 2BEIGH3 has three hot-ends that all mount the same.
1.   0.62mm for low res or large parts.
2.   0.42  for most prints
3.   0.32 for hi res small items
  0.32 is about the limit of the X-Y table stepper drivers.  Anything smaller and we'll need to get drivers that are smaller than 1/16 step.
The hot-ends mount the same and connect to the same material tube.  I have a different config file in slic3r for each nozzle.
I designed the 2BEIGH3 so you can use other extruder and hot end designs.  Again, I want people to hack the 2BEIGH3 for their needs.

Please note the assembly photos.  
The intent is as follows:
1. Show the material path through the unit
2. Show and provide more detail on the location of the bearings, washers and slotted (hobbed) screw.
3. Show the spring loading.
4. Show the added plastic tube that directs the material outward.
5. Show the tapered Delrin block that presses the material against the slotted screw.

I have also uploaded the 2D dxf files rotated for some CAD systems that want everything on an XY plane.  These are denoted with an "R".
NOTE:  (The photos show a Red Nylon small gear as I am getting ready to design an all Nylon Extruder and am currently testing gears.)

Step 17: 2BEIGH3 3D Printer Hot-End

The 2BEIGH3 hot-end is designed for quick replacement or swap out from job to job.  Just 2 screws mount the device to the Z Axis board.  The Heater connects with standard electrical spade lugs and the thermocouple uses one of the support 6/32 threaded rods.  Because there are minor differences, you'll need to re-zero your Z Axis.

The 2BEIGH3 uses two tip types.
The first is the lower resolution tip.  This is a .023" mig welding tip. See http://www.thingiverse.com/thing:7814
The small aluminum block is tapped to 1/4 - 28....there we go....knew we'd use that  1/4 28!
The mig welding tip is drilled out with a 1/8" bit to about .200" from the tip.
The white cylinders are the Teflon/PTFE tubes we ordered.  One inside the other.

Careful with ABS
While this hot end is designed for NYLON, it can have issues you need to watch for with ABS.
ABS changes states much faster than NYLON, and when you use ABS with this hot-end, you must not let the ABS idle in the hot end as it will tend to pool inside and the extruded material will start to vary in thickness/dia.  What this means is that you should always retract a few mm's of ABS or PLA material while preparing for the next print.
I typically have a 1/8" tube blowing cool air on the lower section of the white cylinder where it meets the aluminum to keep ABS from pooling.

High Resolution Nozzle
The second Hot-end nozzle is a higher resolution unit that you may already have in your tool drawer.  I have a free handful from a vendor as it had his LOGO on it.....A pocket oiler
It is made of aluminum
It is threaded
It has a 0.5mm ID that we can roll to a smaller ID
It's cheap
They're everywhere.  Even Amazon has ump-teen flavors.
(Of course you need one like in my photo, not an all plastic oiler)

Since I got my printer up and running, I have been printing parts for work and friends.....it's almost always printing or cutting!   The 2BEIGH3 can print a 55 degree undercut, but starts to drop threads after that.  So you have to design with restraints in mind.  More on that later.

BOM
1 each         1/2 OD x 1/4 " ID Teflon/PTFE Tube - each hot-end needs about 4"  MMC PN 8547K31
1 each         1/4" OD x 1/8" ID Teflon/PTFE Tube - each hot-end needs about 5"  MMC PN 8547K23
1 each         #8 washer
1 each         Coupler MMC PN 51215K106 or any HW Store
4'                   3/8 neopreme tubing (Plumbing Section of your HW Store) Cut to fit your installation.
1 each         #6/32  x 24" threaded rod
4 each           6/32 nuts
1 each           120 volt heater cartridge MM Carr PN 3618K119
1 each           aluminum block  Cut from MMC PN 6023K291 -
                       Multipurpose Anodized Aluminum (Alloy 6061) 3/8" Thick X 2" Width, 1' Length
1 each           0.023" mig welding tip - Harbor Freight  $10 for 5 pc's
2 each           male 1/4" spade terminals for #16 awg wire
1 each          ring terminal for the thermocouple
1 each           Delrin 1" x 1" x 4+ "   MM Carr PN 8739K92  each hot-end needs about 4"
1 each           1-2 amp 120 volt Light Dimmer
                       The Heater cartridge draws .56 Amps at 120 volts and a nominal 300ma at the printing temp
                        It is still not a light bulb, so we need a good Light Dimmer capable of 1+ amps.
                         The Heater cartridge is isolated  and CSA approved but you still need to use covered Spade terminals for Safety.
NOTE: As to PTFE or as the rest of us know it “Teflon Non-Stick Coating for cooking utensils” is of course the famous Dupont coating used by millions for cooking. As any inventor or designer wants those that duplicate his efforts to be safe, I’ll take a few lines to explain where concerns originate.
Since it’s invention back in 1938, there has been something known as the “Teflon Controversy”.  And to this day it is taught in colleges and universities.  A Google search on the term “Teflon Controversy” will provide you a wealth of insight.
As for an in-depth and scientific description of Teflon Non-Stick Coating for cooking utensils, this site is a good start.
http://en.wikipedia.org/wiki/Polytetrafluoroethylene
As the author of this instructable and the designer of the 2BEIGH3, I am not a polymer specialist and can not speak for Teflon Non-Stick Coating or as some refer to it PTFE.
I can however, define the usage of Teflon in the actual 3D NYLON printing process.
1. While the heater cartridge can reach temperatures as noted 600F, this is not the actual printing temperature, as NYLON would boil at that value.
2. The actual temperature at print time is about 20 – 25 degrees above that of ABS.
3. The circular area of the Teflon Non-Stick Coating that comes in contact with heat is ½ inch”,  12mm dia. Or about 1/1000 of an
average frying pan.
4. The temperature at the point of contact on the hot-end is about 10 to 20 degrees higher than most people cook their meats but
certainly not as hot as an unattended frying pan left on the stove-top.
Again, this author respects and appreciates everyone's comments.

Assembly
Cut/Saw and Drill the Delrin per the print
Cut and Drill the Aluminum per the print
NOTE: The ID of the larger tube is slightly smaller than the OD of the smaller tube.  After you have cut to length, place the larger tube in a vice or clamp and run a 1/4" drill through it's center.  We want a snug fit, so don't go larger than 1/4.  Otherwise hot plastic will find a way between the two tubes and as it expands a bit will start to limit the smooth flow of material to the aluminum block.
Chamfer the Top outside edge of the 1/2" tube so it's meets snug with the delrin.
Chamfer the bottom outside edge of the 1/4" tube so it'll sit guided into the top of the 1/4-28 hole.
    Note, this is where your plastic and NYLON will leak if there's not a good pressure seal.  The design is such that as you screw in the top connector, it will push the 1/4 PTFE rod down and apply pressure to the chamfered end.  This is not fixed, as the PTFE will expand the first time we heat it up.  If you notice leaking around the 1/2" tube and aluminum block, tighten the connector to apply more pressure to the inner tube.  The washer keeps the inner tube from sliding up into the connector.
You'll need to tap threads into the top of the Delrin block.  This is an "NPT" thread.  As Delrin is easy to Tap, and Tap's are expensive, you can do as I did.   Just take a old peice of 1/2" pipe and use your dremel to cut about 12-14 slots in the threads as shown.  Works great!  Again, time vs money.
Wrap three turns of Teflon tape around the threads of the mig tip.
You will need to drill with a 1/8" bit into the mig tip to about .2" from the tip
Use a sharp bit.
Use a very slow speed on your varible speed drill.  The metal is very soft.
Use oil...then use more oil.  10W 30 works great.
The drill process will push some of the metal out the tip.  Pull it out .
The 0.023 hole will still be clogged.
Use a 1/16 drill bit and just tap the bottom of the drilled hole....like you were going to complete the hole with a smaller bit.
DO NOT push something from the tip in.....Take a small wire and push from the inside (where you drilled) out and the shavings will come out the tip.  Use compressed air to blow out any other flecks of metal.  If it won't open up, tap it with the 1/16 bit again.

Crimp the Spade terminals to the heater cartridge wires.  Do not solder as at 320c, they'll come UN-soldered.
Screw the tip into the aluminum block - tight.  Be careful not to strip the tapped hole.  The goal is for the heater cartridge, to heat the alum and therefore the tip.  Measure and cut your threaded rod, install the thermocouple and you're good to go.

The threaded rods are in my photos slightly bent.  This is due to an earlier insulator design that wouldn't hold up to the mechanical stress.  And rather than cut new rods, I just bent these into position.

As to the light dimmer, it was to get us up and printing, but of course we'll want a more accurate way of maintaining temperature.
I suggest  using a standard industrial PID controller.  There are several on EBay for about $20.00 or so.
Below is a photo and wires labled so you can see how one is connected.  These always lack "how to" info.
This uses a "K" thermocouple.  It will come with a fancy plug, but cut it off and simply cross the two wires.  Where they cross the first point....that's where they sense.  This means you can twist the wire a few turns, but only the first "touch" is sensed.



Step 18: 2BEIGH3 3D Printer Operaton

I have posted some videos of the operation of the printer and CNC.
I will address NYLON as it uses a modified process from ABS.  You can view hundreds of ABS time lapse printing videos on YT and I would suggest watching these to get an idea as to how these units work.

Here we Go!
Make sure all steppers work.
Do not load NYLON yet....let's make sure all the motors work together.
Load the 2BEIGH3 gcode test file into Mach3.
Center the nozzle on the table and about 2" up.
Zero all 4 axis as we did earlier.
Hit "Cycle Start" and watch to make sure everything is doing what it should.
All four axis should be doing something during the first layers.
Reset and rezero
Place a sticky note paper under the nozzle
Move the nozzle down till it touches the sticky note paper.
The nozzle should "just" rub the paper, just enough to know it's there.
Zero the "Z" axis
Move Z up 5mm and over so the nozzle is not going to drip NYLON on the table as we prime the tip.
Load the NYLON
Make sure our 4th axis is pushing the NYLON rod thru the tube.  The Numeric "+" key and "-" key control the 4th axis
Install the output end of the material tube into the top of the hot-end.
Pres the + key and watch the long tubing.  When the NYLON get's to the cold tip, it'll shake the long tube a bit...you have active pressure in the long tube at this point.
Now, turn on the light dimmer to lowest.
Turn the dimmer up to 15%
You should watch the thermocouple temp start to rise. 
If not, check your wiring and meter settings.  DO NOT Touch the Alum block to see if it's warm.....it may be HOT!
Keep increasing the dimmer knob at 4 min intervals at ~5% till the temp reached 250 c
Nylon may start to drip out of the nozzle....this is a good sign.
Caution here, not all thermocouples are the same.
What we're after is a nice pile of NYLON thread on the table from the nozzle.
We're not going to print just yet.
As you approch 250C keep tapping the + key.....a tap...don't hold it.
You will hear the sound of what sounds like boiling plastic.
At this point, you're close to the right temp.
Remember, once we get to the right temp, we need to "Mark the Dimmer Knob" so we know where to set it the next time.
When the NYLON starts to run out in a thin line, you're there.  You can hold the + key for 2 sec and a stream of NYLON should come out the nozzle.
Here's how to tell if your temp is right.
First, stop worrying about wasting NYLON....if you waste the whole $3.00 rod, it's worth it
As the NYLON comes out of the nozzle, it will look one of three consistencies.
1. Very clear and shiny like toothpaste.  It's to cold
2. Very clear, yet with lots of what looks like bubbles in the stream.  This is correct.
3. A dull stream with a foam like texture.  This is to hot.
When you get a good stream, it's time to clk the Mack3 Cycle Start button.
If all goes as it should "Welcome yourself to a new world of creativity".......!





Because the Hot-End is designed to handle very high  temperatures (450 c), I have ordered both Delrin and Polycarbonate in 3mm rods!
Delrin is considered to be the work-horse of machined/tooled plastics.   I have been told that Delrin may not be usable as it should loose a binding component in the thermoplast process, but a rod is only $2.50, and worth the effort.
Polycarbonate has similar properties along with its translucent qualities.
I'll add instuctables and refer to the 2BEIGH3 as these efforts progress.

One last safety tip.  Find a way to add a limit switch that will turn off the heater power at the end of a print.  Look at my slic3r config file under gcode and you'll see I send the X axis off about 8" in one direction.  There's a limit switch at that location that turns heater power "OFF".

The Linear Bearing noted earlier is up on the Autodesk123D gallery.  This is a good test part to determine if retraction can work in your configuration.   Remaining threads should be "out" of the BB raceway.
The file or part is called "Linear Bearing 912" by taulman

Update - Printing with Clear Acrylic
Below is a video of the 2BEIGH3 printing with 0.125” Dia Clear Acrylic Material
As you might imagine, there are several differences in printing this type of material as compared to ABS, PLA, NYLON, etc.…
This printing is made possible by the taulman 4 orifice Hot-End.  This Hot-End is more complicated to build, than the already documented taulman NYLON Hot-End.  I have designed it in such a way so you can easily get the parts from our present list of vendors.  I won’t document the 4 orifice Hot-End here as this Instructable is already very large.  If there are enough requests, then I will write a sub-instructable…(if they have those?).
I will point out a few items of interest to those that may want to print in acrylic.
First, the performance of the Printer and Hot-End for Acrylic:
1. Resolution - While the resolution of the 2BEIGH3 is fine for other 3D printing materials, the optical properties of acrylic are such that it will amplify any positional anomaly.  With ABS and PLA, we get nice straight lines of plastic.  This is due to a how each thread cools as it is printed.  With acrylic, the material cools so quickly that every step in the stepper motor, every jar of the print table, slack in the belts, backlash in the pulleys and maybe the neighbors kid crying will modulate the oval reflections of a thread as it is positioned.  And because the threads are oval and optically clear, they will amplify these artifacts.
To understand this, you need to know that round optics, or spherical optics have little or no DOF.  And because of this, become more of a reflective device than an optical collimating device.  The best example I can give you is a laser level, one that puts out a thin laser line.  The laser is just any laser diode.  The optics to convert the beam to that fine line…..is a simple glass or plastic (acrylic) cylinder.  The internal reflections of the laser becomes reflective and transition out in all directions along the cylindrical axis, i.e a thin line.
2. Impurities – read “bubbles” – As you watch the video, you’ll see that the initial thread of acrylic from the Hot-End has bubbles.  Unacceptable, of course.  The material must be modified and bubbles eliminated just prior to the material leaving the tip, otherwise, the end part would not only look visually unappealing, but it would have tiny dangerous sharp edges and be easily crushed.  The 4 orifice Hot-End takes care of this and after the first 40-60mm during a print, bubbles cease.
3. Optical properties – I doubt that you will ever be able to print usable optics with this method.  Even perfectly round fibers arranged in any configuration do not lend them selves to any type of collimating ability.  You may be able to print refraction gratings, but even those would be unacceptable to any higher end optical systems.
4. For those with existing 3D Print experience:
A heated table is not used or required
Any masking tape with wax on the back, blue, white, grey…. will secure the part
Requires a Higher temp than ABS
3mm material will shatter on a storage roll
3mm material cost is ~ $0.20 a meter or less than a dime for 12”


Now, back to the 2BEIGH3……

Step 19: Current List of Materials That Can Be Printed on a 2BEIGH3

  These new materials will hopefully drive an increase in new designs by engineers, inventors, artists, hobbyists and anyone who needs anything that has been unavailable in the past.  Anyone from the professional, to the designer of home crafts will now have a wealth of materials and capabilities to make their visions, designs, crafts, inventions or just a fix for the water heater, come to reality.

  And, of course, the infamous PET.  The plastic from Billions of discarded water bottles.  Truth be told, the reason these are not recycled is that.....no one would want to drink from a "used" bottle (according to BW marketing folks).
  So....if you're an environmentalist or just desire to be environmentally responsible, how can you use this technology?

  Here are some of the photos of the current materials with notes:

(Please note that Crystal Clear Polycarbonate is incomplete at this time.)

The last image is a photo of where to replace the step signal opto isolator with two short jumper wires.  Simply cut the opto leads and replace with wires/jumpers as shown.  This will by-pass the opto and provide the full signal to the 7414buffer chip.  This should eliminate skipped steps and or sputtering steppers.

Make It Real Challenge

Runner Up in the
Make It Real Challenge