|
You probably only need 2-3 layers of BID, buy it as
sheet,
The technique I use to avoid too heavy a layup
is:
Buy some 2 mil plastic material, cut out a sheet
twice the size of your layup, fold in half, mark the shape of what you want the
finished piece to look like with felt tip marker, weigh the plastic, turn the
plastic over, lay down number of plies of BID desired, fold the plastic over the
bid (make a sandwich of plastic, cloth, plastic) weigh the plastic/cloth
combo, subtract the weight of plastic to get the weight of cloth, mix an equal
weight of epoxy and pour onto cloth. Lower the plastic back into place, and
squeegee / roll the sandwich until you can see the marker through the sandwich.
squeegee out the excess epoxy and then cut with a rotary wheel cutter on the
lines. Now you can peel off ONE side of the plastic, carry it to your tape
covered foam piece, position it, and peel off the other side. Apply sheet
peel-ply and brush it down using a hair dryer to remove excess epoxy and let
cure.
Bill Schertz
KIS Cruiser # 4045
----- Original Message -----
Sent: Saturday, May 22, 2004 8:51
AM
Subject: [FlyRotary] Fiberglass
Help!
Ok, you fiberglass types. I need some
guidance. I can (and have) slapped resin on glass cloth and obtained
a functional (if heavy) item. However, I am about to start work on my
new radiator ducts and I would like to do better. My ducts will be
approx. 4"x4" at the inlet and approx. 9"x10" at the core. There might
be as much as 1 psi pressure on the walls (if I should ever be so lucky to go
that fast).
There a some semi compound curves at the corners
of the duct as it slopes inward from the top and bottom from the core to the
inlet.
I need your recommendation about the weight and
weave of the cloth. I have previously used the cloth tape as it was easy
to manage, but it required several layers and it is a bit heavy. Like I
said functional but not pretty nor light.
I would like your guidance on how best to apply
the sheet to the mold. In the past, I basically wrap the foam mold in
duct tape and the lay resin on it followed by raps of the cloth tape and more
resine. I am told that using sheet rather than the tape and first laying
it out on aluminum foil to wet it and then cut it in sizes say to fit a side
of the 4 side foam mold with a bit for overlap with the adjacent sides was one
way to go.
Any suggestions would be
appreciated.
Ed
Ed Anderson
RV-6A N494BW Rotary
Powered
Matthews, NC
|