Portable, homemade CNC machine WIP

[robm]

Yep, sure do, at least for the family cars. I've got two Craftsman tool chests and matching set of drawers for each. I should take a couple more pictures of the garage once I get it cleaned out, I've got a regular workshop going out there now what with the multiple table saws and such.

My wife is lovingly indulgent in my various hobbies, which are woefully plentiful. Woodworking, sadly, is not something I'm wonderful at, mainly because this CNC machine is the first real woodworking project I've done... ever.

 

[robm]

Double posting.

Stepper motors came in today! Thanks Sam!

 

[βeta]

Why would you ever need MULTIPLE table saws?

 

[robm]

One is your standard table saw, the other one is a miter saw.

Also, assembled the bearings to the gantry slides today. Work real well. Will take pics later.

 

[βeta]

Bench saw =/= table saw

 

[robm]

It is if the saw is not mounted on a bench, but on a table instead.

 

[βeta]

A mitre saw is not a kind of table saw, they just both bench saws.

 

[robm]

Woodworking, sadly, is not something I'm wonderful at, mainly because this CNC machine is the first real woodworking project I've done... ever.

 

[robm]

Y axis stepper motor installed:

 

[βeta]

Not a woodworker, yet you have the tools. XD Did you get them just for the project? Also, looking good!

 

[robm]

The miter saw I inherited from my in-laws when they packed up and moved to Florida, the table saw we bought when we bought the house because the previous owners took all the baseboards. I don't really count making relatively simple cuts as being woodworking, though.

I put together the y axis control nut assembly (I'm not sure if that's the actual machine name for the part but whatever, it is now) last night. It's what the lead screw from the stepper motor threads through, the nut assembly being attached to the gantry.

 

[βeta]

Coool. Free tools are best tools.

 

[techknott]

Rob, what are you planning to cut with it? What spindle do you plan to use? How much torque do your motors have?

 

[robm]

I'm using a Dremel 9001 whatever model, one of the higher-end ones. The torque rating isn't stamped on the motors, but probably in the 10-35 oz-in range. Not a whole lot of power, but I'm only really planning on PCB engraving - very little force required. However, I do plan on upgrading to the size that Sam sent me, which have "10 lb" stamped on the ends of them. At that point, I'd like to do some light aluminum work.

 

[techknott]

If you're only milling pcb's for now then cool. But if you're going for wood or plastic cutting, I'd advise you to invest at least in some linear rod and proper support brackets. Otherwise you're going to have to cut down at a rate of maybe .25mm per pass and slow at that, forget aluminum.

I ask because I built a first machine using gas pipe and L-plate bearings on mdf. It couldn't cope with the torque that the motors were providing on x and y, even at shallow depths and just ended up twisting.

If something has ever gone wrong with a cnc machine, I've probably experienced it. I have one built from aluminium and steel now and even that struggles with aluminum cuts using a 1000w spindle and 2nm motors.

 

[samjc3]

As far as linear rod, you should totally use Roll-on. I realize its only a ton over what you will need, but its so epic! (Used it before; never seen anything roll so well.)

Also, if you need a third motor like those one I sent, I may be able to scrounge one. The machine they were from had several, and they have been replaced, so the old ones gotta be hanging around someplace.

 

[robm]

@techknott: Awesome, if I run into any issues, mind if I shoot you a question or two?

@Sam: That would be sweet

In any case, yeah, this thing is really only intended as a portable PCB machine than anything else, though obviously having the ability to cut something harder would be great.

 

[techknott]

Sure no worries. Ask away

Also, I don't know what controller and drivers you plan on buying(or making), but check out the Chinese 5 axis all-in-ones on eBay. Honestly, they're dirt cheap and are actually pretty good. They don't come with any info at all but I sussed the pinout(took ages).

 

[robm]

That's exactly what I was planning on doing, so that's good. What did you end up using for a power supply? The 17's are 24v motors, though apparently they can run at 12v.

 

[techknott]

I got my power supply and steppers from a company in the US called probotix. I also got some drivers from them but they were absolute crap.