GLASS GOOSE GAZETTE * ISSUE #17, June 15, 2000

Page 18

with. By then the adhesive will be kicking and you don’t want it to stiffen up too much to squeeze out after all this? Get the weights on as QUICK AS POSSIBLE! Needless to say, place the weights on GENTLY to avoid damaging the wing skin. Do Not put anything stiff like a board on the wing between the individual weights and the skin. I know it would seem that such a protective layer would seem to make sense, but we have found that it is best to just gingerly place the weights directly on the surface. The primary objective is to get the spar cap down into total contact with the spar flanges. Anything that would interfere with that happening is inadvisable and a long board on the skin does just that. You just won’t get consistent squeeze out with a long board. Small short boards under EACH individual weight are OK, but don’t use a long board to span under multiple weights.

At first you may not think you are going to get good squeeze out. But everywhere there is a heavy weight, after 5 or 10 minutes, you will see a small roll of material evident along the edges of the spar that you can see. There may be a few small spots that the roll doesn’t quite make it to the edge, but if you have about 1500 pounds spread along that spar, you will have a good wing. There will be some areas where the squeeze out will be very heavy like down at the BL 65 bonding strip. I always stick a long piece of electrical conduit down in there and try to scrap off those blobs and bring them out. They are just added weight to the wing that serve no purpose.

If you don’t get as much squeeze out as you think you should, remember that the flanges on each side of the spar are somewhat flexible. They will naturally flex down away from the pressure of the squeezing of the Dexter-Hysol. The Hysol will be squeezed very thin in the center just over the spar, but out toward the edges of the flanges, it will be thicker. The flanges are supported in the areas of the ribs and you will notice much heavier

squeeze-out on both sides of the ribs. There is nothing bad about this scenario. I am only explaining it so you will understand and not wonder if something is wrong because the squeeze-out is not completely uniform when you know you applied the Hysol uniformly. You don’t need to add any glass to the flanges. You don’t need to add any ribs. Just build it the way the plans say to build it and this explanation will merely help you to understand what you are seeing when the time comes.

Bert MaWhinney made a suggestion that has worked well for us. Place plastic wrapping material on the lower skin surface inside the wing in all the areas where you will be able to pull it out after the upper skin is in place. Any drips from the squeeze out will fall on the plastic and you can pull the drips out with the plastic later! This will work on the front compartments, but not the back fuel compartments for obvious reasons.

Look in through the leading edge crack with a flashlight before you put the leading edges on and you will be able to view the squeeze out in the forward fuel tank area. This process works so well that if there is squeeze out showing on the front side of the spar, it is virtually impossible for there not to be squeeze out on the back side. But for peace of mind, you can look in through the cleco holes and view the back side as well. You have to get your eye up REAL close and if you have deminished near vision brought on by increasing longevity, you may want to get a youngster to do that looking for you.

Make sure the shear web is cleco’d firmly end to end because it tends to pull away at the ends . Wipe off the squeeze out at the ribs on the leading edge. Apply the leading edges and cleco them in place. Be sure to place saran wrap over the rib points before applying the leading edges to prevent bonding the leading edges at this time.

GLASS GOOSE GAZETTE * ISSUE #17, June 15, 2000

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