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Mike Shoemaker
02-23-2007, 11:20 AM
Will UHMW hold screws? I've never worked with the stuff. I'm thinking of making a crosscut sled. Thanks, Mike

Bob Wingard
02-23-2007, 11:25 AM
Yes, it will. In fact, since almost nothing will stick to it, that is probably the best way to attach it.

jonathan snyder
02-23-2007, 11:44 AM
Mike,

It makes nice sled runners, as it is not affected by humidity and has low friction. It works nicely with a hand plane if you need to take just a smidge off for a good tight fit. If the runner is a bit loose in any one spot in your mitre slot, give the screws in that area an extra turn and that will compress the uhmw and push the sides out giving you a tighter fit.

The down side is it is not cheap. Check a local store that sells plastics.

Jonathan

Edit, Just to clarify, you have to do put the screws in from the bottom as Glen suggested so the head of the screw will compress the runner and widen it to take up any slop.

glenn bradley
02-23-2007, 11:46 AM
UHMW for runners or for the table? I drilled stepped holes in my UHMW runners and used round head W/S to attach from the bottom; heads recessed into the UHMW. I would do this as opposed to screwing down from the top if that is your intention. In general UHMW machines well and takes threads but remember if you screw into it; its soft. I used oak runners on this one because my local supplier didn't have UHMX strips long enough. Normally I prefer UHMW strips for runners as they are not subject to weather / humidity changes.
http://www.sawmillcreek.org/showthread.php?t=50581

Jeff Patrick
02-23-2007, 3:15 PM
You can cut threads into uhmw using a machine tap. I put the screws in from the top. Put the runners into the tablesaw slots and position the plywood sled base..... clamp the base so that it cannot move. Drill down through the sled base and into the uhmw in one pass using the proper drill bit for tapping. Then tap the holes and drill out the plywood sled base to clear the screws, then countersink. The runners will be perfectly aligned. There is no need to design in replaceability for the runners, as they will outlast the sled.

Mike Shoemaker
02-23-2007, 4:41 PM
Thanks for all the responses. I found some on Peachtree, for a good price. I'll get some and try it.

Daniel Rabinovitz
02-24-2007, 10:58 AM
Wow!
Am I thinking the wrong thing.
SLED - Something that goes down hill on snow - correct? :confused:
Nah!
It's only because I saw UHMW in Las Vegas, many years ago - two beautiful young ladies were skating on the stuff, on a demonstration floor. The company that was advertising, with these skaters, was sell UHMW, for use on the insides of dump trucks. To allow sticky material to swiftly slide out of the dump body.
A little history from Daniel (ah! they were cute):D

Ted Miller
02-24-2007, 11:05 AM
At work one day we were demoing a public restroom and the panels surrounding the toliets to my surprise were made of UHMW, now I have one huge sheet that will last my lifetime, what a find...