RE: Sig Tri Star Build
Fuse assembly in this plane is a challenge. The ply doublers and tri stock was added. Then I inspected and sanded the edge that accepts the sheeting for a tight fit. Other kit's I've buit call for pinning a side to plans or had tabs on formers to keep things lined up. None of that here [&o] The fuse tapers fore and aft while the top is a gentle curve. pinning a side to the table and monting formers at 90deg was my plan but I wound up using epoxy for the F4 and F1 former for strength and to give me some time to be sure the fuse was straight and not twisting. Wood scraps were pinned to the table to keep pressure on the sides at F1 with a weight on F1 and a clamp at F4. the fuse was checked for level side to side the bubble in the level is forward due to the downthrust built in. A thin shim on each side corrected that and it was spot on.
Pete