I've been a little unhappy with the plastic guide rail dust covers that come with the Avid pro machines. The problem is that my shop is an unconditioned steel building, so it suffers from temperature extremes of 20s in the winter to 115 in the summer (with 40 degree daily swings). Those plastic covers tend to expand and warp up in between the hold down bolts. Picture below. So I decided to get some 1/4" aluminum stock and machine ( on the CNC... "machines building machines!") them as replacements.

I modeled them in Fusion 360 and made recessed bolt holes similar to the plastic covers. Of course, I also need to cut a dado on the underside at 3/4" by 1/8" to allow clearance for the guide blocks. At first I tried doing this on the table saw (both vertically with an aluminum blade, then flat with a dado blade), but holding them down consistently proved to be a problem (not to mention that it generated aluminum flakes that I'll be cleaning up for a month....).

So I finally ended up just putting it back on the CNC and machining the dado 1mm x 1.5mm on each pass. (Sorry, forgot to pictures of that).

Below are all the pictures and final results, very happy with it!

Bits used:

Amana tool: #561776 - 1/4 O-flute aluminum

Accupro: #43027382 - 1/4 x 2 x 4 3 flute aluminum

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