[holobox]

Getting very close to completing the ~4ftx4ft CNC assembly using 8020 extrusions. I spent quite a bit of time making the linear slide design work with the 2inch extrusion - there are 16 bearings in each slide. The trick was finding bushings to bring the ID of the bearings down to 0.25" to match the T-slot. These motors (425oz-in) are unnecessarily large but were had for a good price. I worked the shaft for the gantry drive inside of the gantry bar, there are 7 bearings along the length to keep the shaft centered in the extrusion to eliminate whipping. Just got the drag-chain and wiring done this weekend.

Attachment 253036
"FuelCNC" - I have no idea why this name stuck

Attachment 253034
Build envelope will be around 40inch x 44inch

Attachment 253038
There's a lot of stuff riding up there. I may need to go with smaller motors at some point. I made a simple torch holder out of polycarbonate with a spring-loaded touch off switch. There will be plenty of experimentation here.

Attachment 253040
2:1 reduction on the X-axis

Attachment 253042
2:1 reduction on the Y-axis

Attachment 253044
Finishing up the wiring this week.

Most of the side plates, etc. are 6061 Al cut on my CNC router using a fantastic cutter from Onsrud and a stream of compressed air aimed at the cut to remove the chips. Very impressed with the cut quality on these pieces. My CNC router is a DIY also based on the BlackToe design over at buildyourcnc.com - it is a workhorse!


Now it's time to design the table this will sit on. I'm going with a downdraft design. Anyone got a design that they like?

Charlie

[mcv]

great build, post some picture when it is cutting

[repauli1]

Your electronics will be ruined in short order..the need to be off the table, in a enclosure, with filtered air. The dust from plasma will be attracted to them. Great looking table!

[BTA PLASMA]

8020 is a quick way of building an enclosure but all 8020 are a simple aluminum extrusion that require machining to be strait and flat. You may find your bearings chewing away the aluminum under the anodizing. Their was a MFG of plasma tables that went out of business and we replaced several of their units that were using bearings on 8020 extrusion just like that. Just a friendly reminder to keep it in the back of your head. I would hate to see a fellow CNCZoner pull his hair out.

[repauli1]

I am actually attaching hardened v rail onto the sides for the v wheels to ride on..

[LeeWay]

A plasma machine only looks new when it actually is.
It will never look new again. I second the thoughts that all electronics need be off the table in an enclosure. Plasma dust is very abrasive as well. It's actually a mix of stuff depending on what you cut. If you cut steel, you basically have steel dust. Very magnetic. It will attach itself to all surfaces. Even aluminum. This is where the bearings design you have will fail quickly.
That steel dust will imbed in the aluminum and make a very poor bearing surface.
I understand this may be a test platform just to get you going, but don't be surprised if you need to rebuild after just a short time. You may want to source some type of dry lube for the chain.
I have seen a few machines that use chain though.

[HorseN]

Nice build Mind telling me what size of 8020 you used for this? how has it been holding up?

Thanks