Easy to Build Desk Top 3 Axis CNC Milling Machine

Step 3 X it Stage right

Take a piece of plastic(I used Plexiglas) or metal, something strong and flat and mount a piece of the U channel to it. Now the tricky part. The round thing is a bearing. You can get them out of motors or buy them at a hardware store. Mount it to a short piece of aluminum like so. Then take a 1/4 in. coupling nut(a long nut) and wrap it with aluminum like so(see pic.) The bearing will hold the X stage to the X rail and the coupling nut will allow the motor to run the satge back and forth. It wouldn't hurt to grease the skids a little and the nut too.
Here's a video on making the bearing fixture.

Comments

[fgleich]

Here's a source for hobby RC cars, trucks, etc bearings. Try to buy one from Ace Hardware for less than 10 dollars per bearing......I'm NOT paying that amount when I can order a pack of ten for about 20 bucks. Anyway,
http://www.vxb.com/Merchant2/merchant.mvc

BTW, Lowes and Home Depot do NOT carry bearings any more

[bluumax]

They're a great bearing for the price.
I bought 1000 for $270 for my machines.
You can get them by 10, 100, 1000.
10 for $4.95 + $4.95 S&H - 10 for $10.
They ship priority mail in the U.S.
http://www.vxb.com/page/bearings/PROD/608ZZ10
Item # 608ZZ

[malikilam]

You can get the 10 bearings even cheaper from the same company by ordering them on Amazon ($1.64 in shipping charge as opposed to $4.95): http://www.amazon.com/Bearing-Shielded-Diameter-Miniature-Bearings/dp/B002BBICBK/ref=sr_1_1?ie=UTF8&qid=1313250027&sr=8-1

[bluumax]

They come in plastic tubes too, not bags.

[tjuxed]

Remember to cut away FROM your finger so you don't cut away the finger.

[bobbval]

I would take it a step further and suggest investing in a cheap vice so you can hold the tool with two hands and maintain proper control. rotary tools can "jump" from the part you are working on and cause some major damage to the hand which is holding the part (I say this from experience!)

[Mastros]

Yes, I fully agree with that caution. When the screw starts turning inside the aluminium, it will also start forcing the aluminium to take a spin. If you are not holding it really strong, the aluminium piece will hit your fingers like the turning blade of a fan.
-.

[Austringer]

So would you call pressing the start button, turning off the lights and going up stairs to take a shower "away"? I mean it's not close to you, but sometimes it's going to be getting closer.

[chinda.raul]

you can get a pack of 8 bearings from a skate store ... high quality, high volume = good value.

[iklln6]

 tap the screw with a hammer before getting it with the screwdriver to keep it from sliding around.  tapping it will make a slight indentation that will hold the screw in place before the self-tapping edges catch and start digging through the aluminum 

[dop3]

hi great idea! :)
but will the driver work with MACH3 CNC CONTROLLER
????
http://www.machsupport.com/artsoft/index/index.htm

mfg dop3

[zoot686]

If you build Tom McWire's driver shown here it will, as his driver uses the step/direction schema, and Mach3 also uses the step/direction schema.
Both use two pins for each motor driver one pin for step and one for direction, and those can be mapped to specific pins in the mach3 setup/configuration.

[donald.emerson]

Great Idea, would like to build, what is the software that drives the mill? Hopefully it's as cheap as the machine.

[josheeg]

cheaper linux cnc.

[ctrlaltdelete]

Hey what sized bearing are you using and what abec rating? i've got a load of old skateboard bearings that i could use for this ranging from some abec 1s to abec 7s. i'm mainly going to be using a mill like this for making some longboards since it will let me just slap down some wood when i leave the house and come back to a cut board.

[HankMcSpank]

What are the dimensions of the bearings you nare using please? (ie inner hole diameter, overall bearing diameter & bearing width)....even better if you have them in metric!

[Dodgy]

Hank, I think the GREAT thing about this CNC mill as opposed to other designs on the net, including this site, is that it's freely adjustable in all terms. You can make the bearings what ever size you wish, from the 5mm OD ones to the 4 inch wide ones. So long as it all comes together nicely. You also can place 1 or 2 or 3 of them if you want. And you don't have to measure their positions accurately, just judge it by eye. The leadscrew does all the accuracy setting for you. I suggest though, you 2 coupling nuts for each threaded rod (leadscrew) one oneach end of the plexglass (or what ever you choose to use) stage. This way, you can get more stability. Even the placement of the rails isn't critical, as they're just guides. If you make the holes in the U channels a bit bigger than the screws that pass through them, you can adjust it if need be, then tighten them up for stability.

[christophor]

Dodgy, relax. Enthusiasm is great, but you're participating all alone. lol

I have ADHD so I had trouble following all of your posts. But based on what I think you said, I think you should check this out. I think you're going to like it.

These guys took what Tom did here and expanded on it in a good way. They implemented springs. They also put in some other cool upgrades.

In some ways, I like Tom's way better. The RepStrap version is slightly more complicated and I'm not sure if all of the 'improvements' add much value.

http://reprap.org/bin/view/Main/McWire_Cartesian_Bot_1_2

I hope you get something you can use out of it like I did. Good luck.

[josheeg]

I seen reprap does have parts for this design it makes it more accessible for someone like me. I am in NY USA but I am into electronics and circuitboards and mechanical stuff is someone else's specalty. I am considering getting their parts to make this to make my printed circuit boards. Any idea of the trace with sizes this could do? Probably would need a finer screw and pieces for a surface mount ssop package.

[josheeg]

well for 100$ or 125$ finished lazer cut parts maby a place like budgetrobotics would be better. Their expanded pvc might be better and it is easy to work. I do not know about strenth... Also PCB and small detail work interest me I hope this can do that...

[Dodgy]

What keeps constant pressure on the ball bearing race to press it against the rail ? I would use an adjusting screw thru the middle of a compression spring. How does that sound ? I've made a simple diagram to illustrate what I mean. But damn, it's wrong... incomplete and I'm not sure how to do it. I know that all the adjuster screw should do, is possibly keep the spring from bending outwards, but mainly it should increase or reduce the pressure on the spring, like squashing it harder or less.

[Dodgy]

Can we see a side view (cross section) to see how the 2 rails (U channel) , plastic & ball bearing race all come together? Also, what stops the plastic nearest to the T piece from hitting the rail under it? Shouldn't there be a ball bearing race going downwards, not just horizontally ?