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View Full Version : good 1/16" straight bits?



knight_toolworks
05-04-2012, 08:52 PM
the last ones I have been getting (no brand name made it the us) have been unreliable. I am cutting .03 polycarbonate and thats bad enough. I cut it at 1ips with a small ramp and from 7500 to 12k (the 12 tends to somewhat weld the shavings on.
I can sometimes cut for 4 hours on a bit and sometimes as soon as it touches the material it breaks. I put another bit in zero the same and it cuts for 4 hours. Now the thing is I was thinking I was using 2f bits but this last one was only 1f. I have had some of the letter parts break and I don't know if it was because of the 1f or not. some letters only have about .02 between them. but I have cut perfect sheets before with these settings. well the last perfect sheet I cut at 12k but that was more work in cleanup. but I had no broken letters.

hh_woodworking
05-07-2012, 09:45 AM
l Like Precise Bits for small ones and they stand behind them. http://www.precisebits.com/gateways/EndMillsHome.htm

khaos
05-07-2012, 10:39 AM
I have used White side 16th straight cuts in bamboo for hours with very consistent results. Bamboo will fuzz as soon as the blade is dull. Polycarb may be a different experience. I guess mileage will vary. HTH.

I cut at 10K 1.5 ips.

knight_toolworks
05-07-2012, 12:32 PM
I bought some frued as they were the only 2f bits. but I will test others. Polycarb is a grabby material that I always have trouble keeping it in place. these are the last of these 4'x4' stencils I have to cut with a small bit.
I ma going to glue the material down to some plastic cardboard so it does not lift up at all.

Mayo
05-07-2012, 02:07 PM
Hey Steve I'd be careful using "plastic cardboard" or coroplast type of material to stick your polycarbonate on before cutting.

The corrugations may result in an uneven depth of cut because the surface is not really flat and your polycarbonate will follow it if you spray glue it down.

Another choice would be the blue or pink foam insulation sheets.