On Jul 21, 7:44 pm, Phisherman wrote:
On Sat, 21 Jul 2007 18:17:54 -0000, "

wrote:
Ok, setting up my drill press, I've got a nifty speed chart for
different
woods (Hard,soft) and other material (metal, plastic) and
different drill bits, but nothing mentioned for plywood.

DAGS and nothing immediate shows up. Are there
any "rules" that govern drill press speeds for different
plywoods and different drill bits?

Thanks,

MJ Wallace

Keep this in mind: The harder the material, the slower the cutting
edge should be. Most of my drilling is done at 800 rpm, but for large
bits and wheel cutters use 300 rpm. Plexiglas is harder than wood,
softer than metal so the speed would be somewhere in-between. I
consider most ply as softwood (pine), but there are some hardwood
plywoods.

My experience with thermoplastics (PVC, plexiglass) is they
partially liquefy and flow under heat and pressure, allowing the
cutter to grab. With large bits or fly cutters, lube with paraffin
or beeswax, set the drillpress to low rpm, feed lightly, and back
off the cutter frequently to cool it.