Homemade Linear Slide System
Building my own CNC machine, for both plasma cutting and for slinging a dremel around, and after pricing ebay/used/new THK slides and competitive products, I decided to at least try making them myself.
Turned out not to be anywhere near as difficult as I thought it would be. I hope I posted this in the right place; After looking at several forum names I guess it could fit in multiple places, but I chose this one "just because" :D
Some bearings, some square stock, a few drill bits, and a digital caliper makes this easy work. Figured I'd share this since I see a bunch of threads about how to make such things yourself.
Step 1: Making the saddle chassis (need four of these):
http://frederic.midimonkey.com/cnc2/IM001789.JPG
Step 2: Making sure all the holes line up well enough to bolt together:
http://frederic.midimonkey.com/cnc2/IM001790.JPG
Step 3: Machine two spacers per bearing (eight bearings total per saddle). Whit the bearings I selected the two spacers need to be 0.152-0.153" for a tight fit:
http://frederic.midimonkey.com/cnc2/IM001787.JPG
Step 4: Bolt it together and hope it fits:
http://frederic.midimonkey.com/cnc2/IM001791.JPG
Step 5: Make more!
Progress as of 2006.05.25
Drilling out the ends of the stainless, hardened rod to 27/64"
http://frederic.midimonkey.com/cnc2/IM001792.JPG
Tapping to 7/16 course:
http://frederic.midimonkey.com/cnc2/IM001793.JPG
Completed rail, with rail supports. I still have to chuck the end supports and skim them with a carbide cutter to make sure as both ends of the rail are the same height off the chassis. You can see the saddle floating in the middle.
http://frederic.midimonkey.com/cnc2/IM001794.JPG
Completed second rail, with supports, still have to skim the bases of the four end supports. I'll do that in a few days once I swap lathe chucks.
http://frederic.midimonkey.com/cnc2/IM001795.JPG
Anyway, back to making 3/16" ID, 0.153" long bushings :D
Unsupported linear rail flex fix?
After looking at the design for these homemade linear bearing slides which looked to be nearly flawless, I wanted to add a suggestion for those who liked the design but were worried about the rail flexing with the use of this particular design. A couple of options crossed my mind here. One would be to secure the rail to an upsidedown mounted Piece of "T" steel or thin "U" steel that would be the length of the machine with a weld(assuming this material will take a weld and that there is a main support directly beneath the rail). The other option that came to mind was to tap the rail every 12 inches or so and run a few pins(welded) or bolts with steel sleeves or up through the main support of the unit. Welding may be the simpler of the two considering the fact that aligning multiple taps in a cylinder may be difficult for some. There looks to be plenty of clearance on the slides for either option.