How to make a mini milling machine- manual or CNC!

Step 13 Mount a motor! (or a spindle and motor)

I used an old Aluminum block I had in my scrap box to mount the Foredom handpiece. The handpiece has a 1" OD and the block I had was for holding bicycle fork steerer tubes during cutting so it was a perfect fit. You could also use a hardwood block with a hole bored in it with a Forstner bit. The holes in the center of the block are for tightening/loosening the collet.

I drilled a couple of holes in the block and mounted it to the Z axis plate with two bolts. The motor mount was a piece of bent steel that came from an electrical box. The motor is connected to the handpiece with a small timing belt that came from an old copying machine, but I've found that large "O" rings do a good job as well- so do vacuum cleaner drive belts. The end cap of the handpiece is removed and a timing belt pulley is fitted to the handpiece shaft- the shaft is 1/4" diameter. I'm currently working on speed control for the motor and will post an update when that's finished.

I found a similar motor to the one I'm using here. It's a 12v motor like the kind used in a cordless drill. They tend to be very durable and have a wide voltage range. Miniature timing belts and pulleys are available here .

The other option is to simply mount a Dremel tool- no need to worry about belt tension!

Mount some rubber feet to the bottom of the mill and you're done!

I did add some stick on metal ruler scales to the Aluminum channel for each axis- it makes it really easy to get rough measurements. I also made a dial indicator holder that is positionable so I can get really precise measurements from each axis. The indicator in the photo measures in .0001" increments.

I'll be posting the CNC conversion soon along with several handy tools like an indexing fixture and milling vise so stay tuned....

Comments

[jonjon1978]

Wicked project. Its the first one ive done so im strugling with getting some of the parts needed e.g. motor coupled with not having all the right tools aswell e.g. Router. so im going to concentrate on getting all the right tools and materials before i start with the critical cuts and drilling. i have seen the prices of the delrin and thought it would be cheeper to sub it with pieces of laminate floor or do you think it would be better to use delrin? Also im thinking of salvaging a motor out of a hoover but would have to slow it down some how? Do you think this would be ok to so? Many thanks. jonjon1978

[Honus]

Delrin would definitely be a better choice. I would think laminate flooring wouldn't make for as good a slide mechanism. I don't know what speed a vacuum cleaner motor would turn- for cutting wood you definitely want high RPM. Most wood routers turn around 20,000 to 30,000 RPM. Palm routers make for good spindles/cutting heads as do die grinders but they usually turn too fast for metal cutting.

I'll have the instructable up soon (probably within the next month) for the new CNC. It'll be a much higher quality machine since I'm using industrial slides, but it will be very accurate/rigid -and it will be able to machine aluminum.

[kmorgan54]

Was it easy to remove the top cap of the handpiece? I have a Foredom #44 handpiece, and I'm unable to remove it. At least, it seems that I would have to destroy it to do so.

[Honus]

Yep- it just screwed right off. Mine is pretty old though (at least 10 yrs) - maybe they put Loctite or something on the newer ones?

[stalker1973]

nice project, can you explain how did you make the spindle ( the inside ) I follow your projects Greetings Barry the Netherlands

[Honus]

Barry,

The spindle is just a Foredom #44 handpiece. The top cap has been removed and a pulley was attached to the shaft.

There is a guide to making your own spindle here:
http://www.buildyouridea.com/cnc/spindle_05/spindle_05.html