I have five questions about fiberglassing:
- when fiberglassing aluminum onto roughed up fiberglass, should I squeegee
or thin the layer of pure epoxy applied w/ paintbrush to coat the metal?
- when making a layup onto an existing fiberglass part, is it ok to wipe away
excess epoxy with a paper towel?
- Is floxing the appropriate method to build up a ramp to a metal piece
placed over existing fiberglass so another ply can be layed up on top?
- Is floxing between rows of rivets-to-nowhere a good idea to prevent
air bubbles if another ply is to be layed up on top?
- What does properly cured floxed epoxy look like - is it kind of a white
haze under a non-floxed layup? does anyone have photos of flox'd work?
Background:
The gear leg fairings on my RV-3 are hollow fiberglass.
They have a 1.5"x4" aluminum tab to attach to the gear leg, similar to the tab
shown for the aluminum fairings in the RV-3 plans. The tab has 6 "rivets to
nowhere", and it (was) attached to the fairing with a layer of fiberglass that
was broken recently when the fairings were removed. The outer fairings have
what appear to be wear holes where the rivets to nowhere sit snugly.
I'm attempting to re-glass the aluminum tabs back to the fairing.
I have not done fiberglass work before.
I made a test piece with a similar configuration and it seems ok, please let me
know if you have suggestions on what I might do differently.
#1 - remove old fiberglass/epoxy from metal tab. sand w/ 220 grit paper.
#2 - sand inside of fairing where the tab is to be replaced w/ 60 grit paper until rough.
#3 - cut two squares of 7725 bidi, one perp to selvedge, one at 45 deg.
dimensions approx 3in wider and 1.5in taller than portion of tab to attach to fairing.
#4 - mix one pump of west 105 resin w/ one pump 206 hardner. mix for 1min.
within 4 min:
#5 - coat outer fairing where tab is to be attached, and metal tab top and bottom with epoxy.
unclear: how thick should this be? Should I squeegee it thinner?
#6 - place tab onto outer fairing. align wear holes w/ rivets-to-nowhere.
support hanging end with a layer of wax paper'd cardboard to prevent
hanging.
#7 - add flox to remaining resin so that flox makes mixture stand up w/ a
paintbrush. If > 3min has elapsed, mix a new batch for this.
#8 - apply floxd epoxy w/ paintbrush to build up a "ramp" up to the side of
the aluminum tab. Also apply flox w/ paintbrush to ramp up to the "rivets to
nowhere" so that the glass can lay ontop of it without forming a bubble.
#9 - mix one pump west 105 resin, w/ one pump 206 hardner, mix for 1min.
#10- - apply 1 square of 8oz 7725 bidi parallel/perp to aluminum strip, overlap sides & end by ~1.5in.
- squeegee to soak up epoxy from underneath.
- apply extra epoxy if necessary
- squeegee it out
unclear: how to prevent excess from making a mess on existing fairing - wipe w/ paper towel?
#11 - apply 1 square of 8oz 7725 bidi at 45deg to aluminum strip, overlap sides & end by ~1.5in.
- squeegee to soak up expoxy from underneath
- apply extra epoxy if necessary
- pump a new mixture if it's been >= 4min since mixing.
wait 24hrs.
- when fiberglassing aluminum onto roughed up fiberglass, should I squeegee
or thin the layer of pure epoxy applied w/ paintbrush to coat the metal?
- when making a layup onto an existing fiberglass part, is it ok to wipe away
excess epoxy with a paper towel?
- Is floxing the appropriate method to build up a ramp to a metal piece
placed over existing fiberglass so another ply can be layed up on top?
- Is floxing between rows of rivets-to-nowhere a good idea to prevent
air bubbles if another ply is to be layed up on top?
- What does properly cured floxed epoxy look like - is it kind of a white
haze under a non-floxed layup? does anyone have photos of flox'd work?
Background:
The gear leg fairings on my RV-3 are hollow fiberglass.
They have a 1.5"x4" aluminum tab to attach to the gear leg, similar to the tab
shown for the aluminum fairings in the RV-3 plans. The tab has 6 "rivets to
nowhere", and it (was) attached to the fairing with a layer of fiberglass that
was broken recently when the fairings were removed. The outer fairings have
what appear to be wear holes where the rivets to nowhere sit snugly.
I'm attempting to re-glass the aluminum tabs back to the fairing.
I have not done fiberglass work before.
I made a test piece with a similar configuration and it seems ok, please let me
know if you have suggestions on what I might do differently.
#1 - remove old fiberglass/epoxy from metal tab. sand w/ 220 grit paper.
#2 - sand inside of fairing where the tab is to be replaced w/ 60 grit paper until rough.
#3 - cut two squares of 7725 bidi, one perp to selvedge, one at 45 deg.
dimensions approx 3in wider and 1.5in taller than portion of tab to attach to fairing.
#4 - mix one pump of west 105 resin w/ one pump 206 hardner. mix for 1min.
within 4 min:
#5 - coat outer fairing where tab is to be attached, and metal tab top and bottom with epoxy.
unclear: how thick should this be? Should I squeegee it thinner?
#6 - place tab onto outer fairing. align wear holes w/ rivets-to-nowhere.
support hanging end with a layer of wax paper'd cardboard to prevent
hanging.
#7 - add flox to remaining resin so that flox makes mixture stand up w/ a
paintbrush. If > 3min has elapsed, mix a new batch for this.
#8 - apply floxd epoxy w/ paintbrush to build up a "ramp" up to the side of
the aluminum tab. Also apply flox w/ paintbrush to ramp up to the "rivets to
nowhere" so that the glass can lay ontop of it without forming a bubble.
#9 - mix one pump west 105 resin, w/ one pump 206 hardner, mix for 1min.
#10- - apply 1 square of 8oz 7725 bidi parallel/perp to aluminum strip, overlap sides & end by ~1.5in.
- squeegee to soak up epoxy from underneath.
- apply extra epoxy if necessary
- squeegee it out
unclear: how to prevent excess from making a mess on existing fairing - wipe w/ paper towel?
#11 - apply 1 square of 8oz 7725 bidi at 45deg to aluminum strip, overlap sides & end by ~1.5in.
- squeegee to soak up expoxy from underneath
- apply extra epoxy if necessary
- pump a new mixture if it's been >= 4min since mixing.
wait 24hrs.