Step 18: 2BEIGH3 3D Printer Operaton
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……