Trimming/shaping UHMW blocks

[David_Nelson]

Hey Guys and Gals,

What's the best way to neatly trim and shape UHMW blocks? I've tried the scotch-bright wheel on low RPM but that does not seem to do it (maybe for final polishing).

I'm making the tip-up canopy latch guides and I've got the basic block made. Now I want to shape it into something that looks somewhat aesthetically pleasing to the eye.

Thanks,

[hydroguy2]

I use a bandsaw followed by an italian milling machine. here's a pic:

[Mel]

Shape with a belt sander and then scrape the corners with an Exacto knife.

[Greg Arehart]

Or get yourself a piece of delrin plastic that is easier to work.

greg

[hgerhardt]

Originally Posted by hydroguy2

I use a bandsaw followed by an italian milling machine. here's a pic:

That's a Vixen file, and it works the best for the UHMW blocks. It's also important that the file is new and sharp. If it's been used much on metal, go buy a new one. You need to apply heavy pressure and go slowly. The block needs to be in a vise so you can apply enough pressure. Also, hold the file in a 60 deg angle to the block and slide the file lengthwise with the block so that the teeth slice into the plastic. This is not the same as holding the file 60 deg to the work and going back and forth. I'm talking move the file sideways. This takes some practice to master, but it will remove stock quickly and leave a nice finish. This technique works well on metal, too.

Heinrich Gerhardt
RV-6, flying

[rv6ejguy]

A bench grinder with a coarse stone is about 10X faster than a file.