Another thing to note is that you need to make your strokes of the squeegee across the spar and NOT in line with it. If the rows of adhesive are in line with the spar, in addition to rows of adhesive, you also have rows of AIR! When you put the upper skin down on the adhesive and press it down, the air between the rows of adhesive must get out if the adhesive is to give maximum coverage and bonding. To expect the air at the center of the wing to squeeze all the way out to the end of the wing as the rows of adhesive close up is unrealistic. If the rows of adhesive are in line with the spar, that is what would have to happen. True, most of it would get out anyway, but there would be unavoidable pockets of air trapped forever. If the rows of adhesive are across the spar, then the air only has to travel an inch or so as the rows close up to be out of the way of a 100% bond as it squeezes out of both sides of the spar. Neat?

When preparing to close the wing, you will of course open up the can of Dexter-Hysol resin. When you put a stir stick in it, you won’t believe how thick it is! I mean, you almost can’t get a stick in it! Don’t worry, the hardener is water thin and really thins it down. It’s hard to get the hardener to start mixing with the resin, but slowly

We have found that it takes about 1200 grams of the resin to handle closing one wing. Since it mixes with the hardener at 26/100, that means 1512 total grams of material. There is always some left over, so it doesn’t all remain on the wing, But this is the amount that I feel a person should have set up and ready to utilize. Usually we actually only use about 1200 grams total by the time we are finished.

As I said, this material initially is very thick and it only gives you about 45 minutes of working time. Even with a lot of help, you don’t need to be wasting a lot of time trying to dig the resin out of the can and measure it. You want to do all that set up ahead of time. Get 6 good size mixing cups and measure 200 grams of resin into each one. It will be hard to get exactly 200 in each cup, but get close. Then get some smaller cups and measure the correct amount of hardener for each cup of resin and set them up as matched pairs. When the time comes to start mixing, all you will have to do is dump the hardener in the matching resin cup and start stirring.

In a previous newsletter, I explained how flox was a contributing factor to the lack of bonding that occurred on a lot of Seahawk wings and why. I am about to tell you to use flox in the new bonding process. The two applications are completely different, so please do not misunderstand and feel that I am crawfishing on what I said before. That explanation still stands and you can go back in that newsletter and check it out if you like.

We have found that the mixed Dexter-Hysol is just too thin to maintain the amount needed on the spar and the ribs for the bonding process. It needs to be a little thicker to stay in place just the way we want it. Therefore, we add some flox to the mixture to help in this area.