Fiberglass tips....
Having built a Long-EZ, let me share some fiberglassing tips.
1. Once a FG part has fully cured, the only adhesion for subsequent glass layers is mechanical. The part should be sanded with at least 80 grit paper, preferably 36 grit. If the part was originally created using polyester resin, subsequent layups should be with polyester resin, not epoxy.
2. Please use a small ?Dixie? cup and popsicle stick for mixing, not a baggie.
3. Please don?t ?pre-preging? just one or two plies. Once glass cloth is wet with epoxy, controlling fiber orientation is like controlling wet toilet paper, unless it?s fairly thick (like 5 plies). Pre-preg on wax paper if you?re doing at least 5 plys. Transfer the glass to the part you?re applying it to, then peel off the wax paper.
4. Use a cheap 1? brush to apply a wetted out layer of pure epoxy to the component, then carefully apply the single ply of dry glass. Use the brush to stipple in the epoxy until wetted out. You can use a pliable rubber squeegee instead of the brush if you?re working with a larger flat surface. Then apply the next layer of glass cloth? repeat until you have the needed thickness. Wet out a strip of peel-ply over top the layup (all the way to the peel-ply edges) to make a smooth edge transition, or for leaving a rough surface for later applications of glass. (You don?t have to sand a previous layup if it has been peel-plied).
5. Please don?t cure wet epoxy in the oven at temps over 85-90 Deg F. At higher temps you run great risk of causing the epoxy to drain out of the cloth, resulting in a dry, non structural layup. You can use higher temps once the epoxy has cured to at least the tack free state. If you cure it out at 150 DegF, then application of heat to the part to reform it at a later time, will require heat greater than 150.
6. When faced with cold temps for wetting out FG, use a hair dryer on low temp to aide in wetting out the cloth. But be careful to prevent the cloth from becoming ?dry? by the epoxy draining out of the cloth.
7. And please, wear gloves when handling epoxy, the stuff can and will cause allergic skin reaction. It requires solvents to get epoxy off your skin, which will also act to dissolve the epoxy into your skin.
I was almost finished building my Long-EZ without allergic problems, then all of a sudden, it was AWEFUL (that was 1984). I almost didn?t finish the project because of the subsequent reactions to the epoxy. To this day, I break out like a poison oak rash if I get any of it on me.
All fiberglass components (like fairings) must have a tinnerman washer under the screw, otherwise in time, the screw head will work it?s way through the bare FG hole.
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Long-EZ built 1985 -> Sold 2007
RV-9A; N539RV First Flight: 7/2010
RV-8A N468DL 40 hr Flight Test Program
Building Log: www.mykitlog.com/n539rv
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2017 Paid
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