Chapter 19 - Step 3

This step involves cutting all the wing foam and then assemblying the various sections.

Preparing to cut planform February 7, 2003. Here is a set of wing foam blocks layed out with the planform measured out. You can see the straight edges in place.

Preparing to cut airfoils February 8, 2003. Here is the right, inboard section ready to be cut to shape. The planform has been cut and the two templates are in place. You can see the extra foam in place on top.

I heard of other builders using some 3M spray adhesive to temporarily glue the foam blocks together instead of the plans method of using sticks and 5-minute epoxy. I like the idea and dug out the spray I used for sticking the template paper to the masonite. This didn't work at all. The blocks got sticky but the blocks easily came apart. I went down the street to our local Art supply store and bought two other 3M spray adhesives. I tried each on some scrap foam. One partially melted the foam - and this was a foam specific spray, and the other simply didn't hold at all. Being lazy I just decided to cut the foam without gluing them at all. Cutting the planforms was real easy. I simply lined the blocks up properly using marks I made on them, placed some weights on the blocks so they wouldn't move and cut all the planforms by myself - worked just fine. Next, the jigs were nailed into place and the nails easily hold everything together as long as I don't try picking it all up. Careful sliding is OK. After cutting the airfoils I simply marked all the blocks and set them aside for later microing together.

Foam, foam, everywhere February 8, 2003. Here is a shot after I cut all the planforms - there is blue foam everywhere.

Wing template February 16, 2003. Here is a shot of a wing template attached to the foam. You may notice that there are two smaller pieces attached to the template that cover the spar cap cutouts. This allows me to cut the airfoil in two steps. The first pass I just go from leading to trailing edge. I then remove the extra piece and cut the spar cap trough in a separate step. This makes it easier to cut nice straight troughs. NOTE: However, it is important that you still pause at positions 12 and 16 to let the wire lag catch up on the first pass. I didn't do this on some of the cores and it caused the troughs to have a slight sag in them.