RE: Sig Hog-Bipe kit.
The front sheeting is very straight forward, just wet the outside of the sheeting and it will naturally bend over the fuse. I started by glueing the edge to the fuse at the bottom while everything is dry. once the edge is firmly glued to the fuse, I wet the outside of the balsa sheet untill it about layed flat on its own. Then I gently lifted it up and painted the formers and balsa sticks with my yellow wood glue using a small artist paint brush. Then I layed some dive weights (lead shot in small bags weighing between 1 pound an 5 pounds) on the top. I also used tape to wrap around the entire fuse to help hold it in place. For the rear, I just layed the sheet on the botom of the fuse and then rolled it up to the top. Then I marked wher the sheet should be cut to align with the top of the fuse and after it was cut, I rolled it on the fuse again to see where it should be cut for the front edge. I used a fairly straight cut at the front, but I think it started about 1/2" from the bottom edge. Paper templets might be easier, but I just kept cutting a bit at a time until I liked the fit. The bends on the Hog are so gentle, you really don't need anything but water to soften the balsa, and if you only wet the outside it will naturally curl in the direction of the bend.
I don't really trust magnets to hold the hatch as well as I want it to be held. I was thinking on the way home from work, that if I could find tape that matches the color of paint I will use, I could just tape it on there. I have even thought about using some sealant to glue it in place, but still have the ability to slice the sealant and remove the hatch if it ever needs removing. I don't plan to get in there much, but I don't want to tear the entire airframe apart to be able to get in there.