Cutting .028 slots

[srd1@bright.net]

I am not familiar with router bits so this may be a crazy question. Is it possible to get a bit that will cut a .028" slot all the way through 5/8 birch plywood? (this wood is pretty soft) Basicly cut like a jig saw blade. Thank you for any info on this.

[billp]

The smallest router bit I have tried in my Shopbot was a 1/16"straight carbide unit. I tried it in pine, and I tried to make a 1/4" deep cut at .5"per second. It took exactly 2 seconds to snap....I think you might find engraving bits that are thinner in diameter, but I doubt that their cutting length will be more than 1/2". And I'd be ( pleasantly) surprised if they could cut through 5/8 inch material.If the wood didn't break the bit, the glue lines in plywood almost certainly would...Thinnest cut I've been able to get in ply is with a 1/16" Matsushita saw blade which cuts just about any wood like butter, but it's more than twice the thickness you need..

[Robin]

I've used bits that small (engraving game boards and "inlaying" with coloured epoxy) but never more than an 1/8" or so in depth. My speed was set at around .2"/s and I was using 1/8" shank remanufactured bits from the electronics industry. I bought mine cheap (around $8 for 10) from Princess Auto. The tiny spiral's worked better than the rasp type.

[sheldon@dingwallguitars.com]

I have a .025" bit that I will be using in a 65,000 RPM spindle. It's depth of cut is 3/16", I doubt if you could find one much longer than that. You also need the high rpm to keep your tip speed sensible.