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Scratched Ribs

So, you need a rib set.

Often a problem, and one of the biggest hurdles encountered with a scratch build. There are sources, but maybe not for the plane your working on.  I have access to ACAD, so do my drawing there to make sure the spar notches, lengths and heights all come together. The tip panel needs extra attention as there is often a taper in 2 planes

I first cut all the templates from thin aluminum, this type can be scored with a sharp stable knife, and then broke

The heights are cut slightly over, and then I cut the lengths

The bottom is flat, and I clean all the edges as well with a file

I measure and mark everything with a set of calipers as I go along, a couple square files work well when it comes to clearing the notches

Paper and aluminum, ready for the next step

Here I have filed the lower spar notch and the TE lower sheet notch, note the extension of the forward notch edge line thru to the top surface

In order to get the top surface shape I have to align and glue the paper templates to the aluminum

I cut the paper template with a straight cut across the bottom, , rear and front and allow clearance at the top so I can file to the line after

all eight templates glued up and ready to have the top edge cleaned up

the other set also ready for upper surface cleaning

Top edge cleaned up, have measured and confirmed height and added the notch. I will set these together and clean the LE and TE up some more and then they are ready to go.