Cheapish CNC machine

[dirtbikerxz]

Originally Posted by mman1506

I built this machine for about 500$ USD (I haven't built the enclosure yet so it's a bit of mess). It cuts aluminium better than X-Carve or Shapeoko IMO, I can fairly easily do 1/16 DOC at 15 IPM with a 1/8 Carbide single flute end mill. I cut this sprocket on it in about 15 minutes. It's definitely not something I'd recommend to someone new to CNC machining but a practical machine for aluminium can be made for well under the price of an X-Carve.

I would love it, if you are capable of sharing the plans for this. The 500 dollar price range is insane

[techhelpbb]

At $25 a stepper plus say $30 bucks an amp.
That is about $150 to get controls alone unless you salvaged.

I assume $500 is the machine itself?
Prusa 3D printers are in this price range now at not nearly that build quality.

[mman1506]

Originally Posted by asid61

That looks really good! Any chance we can get some plans?

I've seen Shapeoko 3's out-of-the-box cut aluminum, albeit slowly.

Thanks, I'm planning on writing a build log about it soon. The only thing that is custom on the machine is the spindle but that could be made on a drill press if need be. To keep the costs down I imported almost all of the parts directly from China

[techhelpbb]

Originally Posted by mman1506

Thanks, I'm planning on writing a build log about it soon. The only thing that is custom on the machine is the spindle but that could be made on a drill press if need be. To keep the costs down I imported almost all of the parts directly from China

ACME screws or standard threaded rod?
What kind of accuracy and repeatability are you getting?

[mman1506]

Originally Posted by techhelpbb

At $25 a stepper plus say $30 bucks an amp.
That is about $150 to get controls alone unless you salvaged.

I assume $500 is the machine itself?
Prusa 3D printers are in this price range now at not nearly that build quality.

I bought the steppers for $3.50 each and the drivers + CNC shield+ Arduino was another 20$. The frame was about 280$ including ball screws and linear rails. Shipping accounted for about 1/4 of the cost of the machine.

[mman1506]

Originally Posted by techhelpbb

ACME screws or standard threaded rod?
What kind of accuracy and repeatability are you getting?

Ball Screws , I wouldn't settle for anything less. I haven't tuned the machine yet but the tolerances are higher than my chinese digital caliper can read (perfectly acceptable for FRC use)

[dirtbikerxz]

Originally Posted by mman1506

I bought the steppers for $3.50 each and the drivers + CNC shield+ Arduino was another 20$. The frame was about 280$ including ball screws and linear rails. Shipping accounted for about 1/4 of the cost of the machine.

You sir, are a master

[dirtbikerxz]

Originally Posted by mman1506

Ball Screws , I wouldn't settle for anything less. I haven't tuned the machine yet but the tolerances are higher than my chinese digital caliper can read (perfectly acceptable for FRC use)

Our team will do anything, to have access to something like this. There have been several situation this past season where a cnc machine would have been a god send.

[echin]

I have a cheap Chinese CNC router from Ebay at home. The electronics were done poorly and we had to re-work the stepper controllers, but mechanically, it is a fairly good machine. We use these router bits for aluminum and have had great results. They cut much cleaner and faster than a standard end mill, but still are not fast.

[techhelpbb]

Originally Posted by mman1506

Ball Screws , I wouldn't settle for anything less. I haven't tuned the machine yet but the tolerances are higher than my chinese digital caliper can read (perfectly acceptable for FRC use)

Very nice! Will look forward to the build log. I do not know of any sources for good multi-turn ball screws and ball anti-backlash nuts in a price range like that. Usually they resort to threaded rod or nylon blocks heated then pressed and sooner or later that bites you from wear.

Kind of suspect your CNC shield is a RAMPS 1.4?

[dirtbikerxz]

Originally Posted by echin

I have a cheap Chinese CNC router from Ebay at home. The electronics were done poorly and we had to re-work the stepper controllers, but mechanically, it is a fairly good machine. We use these router bits for aluminum and have had great results. They cut much cleaner and faster than a standard end mill, but still are not fast.

Thanks for the advice, will keep it in mind if and when we hopefully get a cnc router

[dirtbikerxz]

What are the differences between an x-carve and a shapeko3? The shapeko 3 website shows videos of it milling into aluminum pretty easily....

[techhelpbb]

Originally Posted by dirtbikerxz

What are the differences between an x-carve and a shapeko3? The shapeko 3 website shows videos of it milling into aluminum pretty easily....

A couple of things to note video is terrible at showing:
Accuracy, repeatability and grade of aluminium.

I have no doubt you can force aluminum into a drill press with an X/Y table as well and it will cut. Eventually the drill press will fail from that but I know folks do it. Some even toss the drill presses and replace them because the presses are -that- cheap they are literally disposable.

[jkelleyrtp]

We actually used the X-Carve to machine our practice robot this year and it did a pretty good job. We put a LOT of work into learning how to properly use CAM software and feeds/speeds but eventually we found the sweet spot for both 5052 and 6061 with our setup. We machined our bellypan, chassis rails, superstructure gussets, and shooter components from components .050" to .1875" thick. You definitely will have better luck with with an actual CNC mill, but for a router, the X-Carve (with mods) can take you just about as far as you are willing to put into it.

[dirtbikerxz]

Originally Posted by jkelleyrtp

We actually used the X-Carve to machine our practice robot this year and it did a pretty good job. We put a LOT of work into learning how to properly use CAM software and feeds/speeds but eventually we found the sweet spot for both 5052 and 6061 with our setup. We machined our bellypan, chassis rails, superstructure gussets, and shooter components from components .050" to .1875" thick. You definitely will have better luck with with an actual CNC mill, but for a router, the X-Carve (with mods) can take you just about as far as you are willing to put into it.

What is the thickest block of aluminum do you think it can work with? (just wondering about the height of the z axis)