[Shonky]

Hi, I've been lurking around for a bit, but decided to share my build, and figured it was better to get input sooner rather than later.

So, as with a lot of these builds that are a bit different, I have something at my disposal which makes me able to do this in a way that isn't really feasible for the majority of people. I work at a medium/large manufacturing company that makes very large stuff out of steel. Anyway, what it boils down to is that I can pay cost price (which is cheap when you buy as much as they do) for the square footage of steel, and then get it laser cut for free.

I'm going to use A572 grade 50 .5" thick structural steel for the frame of my new toy. I'm going to build it with tabs so that it nicely slots together, and should hopefully be reasonably dimensional without too much shimming. It will cost me ~$8.80 per square foot.

I believe that it should stand on it's own without too much interference, but for extra support I will put some tack welds or epoxy it together at the end when I have everything where I want it. I might also use brackets and bolts. I haven't decided on that yet.

I ordered my ballscrews and linear shafts+ bearings off the ebay about a week ago, so they should arrive in 3 weeks or so. I bought them from a seller called momo19830131. I couldn't find a whole lot of info on him, but the one youtube video I did see was favorable. I'll let you know how they turn out when I get them or I put them to use I guess.

On the left-right axis I have put an anti racking system, as described here: http://www.cnczone.com/forums/diy-cn..._solid-13.html We shall see how it goes, but I probably should should have just spent another $50 on longer linear shafts.

On the Z axis I have put an extension up the top with some optional mounts for if I find I have too much slop there. If I am doing thinner, stiffer materials I will take the upper linear bearings off and attach them at those holes to give me greater stability. I will also get around to making a brace for the top there.

The "box" up the top there will also have sides to it when I am done.

At the moment, I intend on purchasing a 381 oz/ G540 kit from automation technology for the electronics of this build unless someone here has a better suggestion.

Total budget is around the $2000 mark including software. Here is my spending estimate so far:
Bought:
mechanicals $562
anti racking parts $30
Yet to buy:
electronics $500
frame $200
Hitachi M12VC spindle $120
precisebits collet set $90
--------------------------------
total so far =1502

I'm sure that number will grow by the time I'm done.

Haven't decided if I will spend on Mach3 just yet or try my hand with LinuxCNC first.

Total travel should be around 500x600x300mm minus whatever it takes to put reliable end stop switches in. In "less Z slop mode" Z travel will be reduced to 150mm.

I'll attach some screenshots of my current design. There's a lot of sky-hooks and things not finalized yet, but it's well on it's way to being done. I want to wait until all my parts arrive and I have measured them before I complete it and send it out to get cut. I'd rather wait a little while than end up paying for it twice. Here's a quick gif showing how the frame should go together, but I'm not sure how long this link will live, and uploading animated gifs doesn't seem to work on the forum. http://gifmaker.me/ViewGIFAnimation....put_fCgSY4.gif

Any suggestions are welcome, and I'll try and keep this build thread somewhat updated with my mistakes and adventures for the good of humanity and all that.

Alex.