What spacing should I use for the screws into the sheetmetal? Also how do I make the threads in the steel formers for the P-K screws?
———- We use 3″ screw spacing on most everything. Adjust for corners etc. Also, on our pre-welded fuselages, we fit the lower skins first, rear to front, then the sides rear to front. Note: When fitting the formers to the fuselage and sheetmetal to the formers together at the same time when scratch building my fuselage, I found it easier to fit everything from forward to aft instead, but I did do the bottom panels first like Kevin suggests- Darin Use #8 x 3/8″ long stainless steel sheet metal screws in most all the alum skins. These are only used where the steel formers or longeron strips are located. Instrument panels, firewall, small bulkhead at lower longeron aft of FW, etc are aluminum, so we use 8-32 nutplates in these places. (cowl uses 10-32 nutplates) The trick is to drill all the attach holes #40 for use of sliver clecos. Do not open the holes up in the steel strips. Typically, people have trouble getting a stainless screw to thread into the steel. So, they open up the ho
