On Sun, 24 Apr 2005 14:46:23 GMT, UltraJohn
wrote:

Kent Ashton wrote:

I've sanding a few Cozy/Long-EZ airplanes and I never had any problem with
rash or dust from that but sanding those UNI landing-gear struts will make
me itch for a day. Somehow those UNI fibers get pulled off longer and
form little needles.

Just a heavy long-sleeved shirt and a regular dust mask will do OK for me.
--Kent



From what I know of fiberglass work your not supposed to sand into the
fibers. Just till you BARELY expose the surface of the fiber. So If your
pulling enough fiber off to stick into yourself and cause a rash you are
way overdoing it.
Anyone else to comment, maybe I'm wrong but I think I'm close!

Pretty much, but not sanding into fibers is getting ready for the next
lay-up. You will sand into fibers when tapering a lay-up such as when
you add a couple layers at fuselage seams and then sand them to match
into the sides and bottom, or where ever they might be. Another
source of fibers (and they really itch) is sanding down a mill fiber
fill. It's normally used in places where you are going for strength
and I haven't run into many places where I needed to sand it, but man!
mixing up a batch, plus throwing in a little Cabosil to keep the resin
from running out is like playing in a roll of attic insulation.

As Kent said, long sleeve shirts with snug cuffs, gloves, Welder's
skull cap (if you have hair) and a good respirator. NEVER sand
fiberglass or resin without a respirator. Make sure it's a good one
too. I work with Vinyl Ester Resin (Derakane) and that stuff is
potent once it has been catalyzed. Smells nice before that. I use a
good organic vapor filter with a dust filter screwed on over it. I
have the kind that uses matching filters that gasket together and the
dust filter keeps the crap out of the activated charcoal.

I typically take the activated filters and put them in "Ziploc bags"
when not in use. Otherwise the carbon is soaking up *stuff* and
shortening its useful life.

I can work inside the fuselage wiping down parts with Acetone and
never even smell it. Just reposition the mask which breaks the seal
to your face for an instant will prove the filters are doing their
job. :-))

Don't take shortcuts and do "just a little sanding" without the mask.
If you are like me a little sanding may turn into an hour or two.

Good Luck,

Roger Halstead (K8RI & ARRL life member)
(N833R, S# CD-2 Worlds oldest Debonair)
www.rogerhalstead.com

John