|
|
Brad writes:
<< Does anyone have a good solution to repairing a pin
hole leak in the leading edge of the wing. I did not
close out the wing, it was done by a previous owner.
It is part of the fuel bay. It took about 50 hours to
leak through. I am looking for a product like hysol,
but do need a whole quart for a little patch job.
Anybody else experience this? Brad LIV-55 hours Still
in primer.
>>
Brad, this problem is not uncommon in the early wings as, during wing
closeout, the leading edges were clamped with a line of sheet metal
screws that are removed then the holes filled. The leading edges are
also prone to voids in the layup. Later wings have a leading edge
"spar" that eliminated this problem and provides a conduit for wiring.
The Jefco epoxy has good fuel resistance and can be used with flox to
patch the pin leak. First, drain all fuel from the wing and park the
plane in the sun with the fuel cap off until the inside of the wind is
dry. Then make a female mold of the area to be patched with some 4
bid. Cover the inside of the mold with packing tape. Ground the wing /
airplane to drain off any static buildup. Next cover the area of the
leak with 2" masking tape then dremmel out the leak. Follow the fuel.
Clean the area with MC. Use a pneumatic venturi pump (Harbor Freight)
and a gauge or manometer to pull a 5-10" H2O vacuum on the wing. Do NOT
use a vacuum cleaner due to the risk of sparks from the motor.
Liberally wet out the inside of the carved out area with epoxy. When
the epoxy starts to kick, mix a fresh batch and wet out the area again.
Mix a third batch and make a runny flox mixture that is trowled into
the patch area. Cover with the female mold and secure with more masking
tape.
After the patch cures you can remove the mold and protective masking
tape. The patch will be slightly taller than the surrounding wing
surface by the thickness of the masking tape. This will allow you to
sand the area down flush to the primered surface. A couple of wet
primer coats later and "Viola" no more leak.
Regards
Brent Regan
|
|