I installed the spar attach fittings with Rib #1 already on the spars. Any suggestions on how to notch the rib so it will go over the spar attach reinforcements. See pictures.
Printable View
I installed the spar attach fittings with Rib #1 already on the spars. Any suggestions on how to notch the rib so it will go over the spar attach reinforcements. See pictures.
I painted myself into that corner also. I vaguely recall that I marked the attach fitting locations onto the web of the rib. Slid the rib out on the spar to provide some working room. Protected the spar with a couple of layers of tape on each side of the web, and used an Exacto and small files to trim away the necessary web material. Yes, it was a real pain.
Dremel tool with cutting wheel (saw) to do most of the work. Finish cut with Xacto saw.
The only problem with the dremel is I was concerned about hitting spar since I can't remove the rib.
I wouldn't be too worried if a little more material than necessary is removed (not a "perfect" fit). Be careful of the spar, & fill any gaps with Hysol & flox if you need to.
Be careful, take your time and don't let the Dremel touch the spar.
Cut more than you need to on the rib. The hysol will fill it in. Get within 1/8" of the spar than stop and break the piece out.
If there is a little bit of space between the spar and rib you could try sliding a piece of .016 (or thicker) sheet metal between them. This would protect your spar from getting damaged by any tools you use. Ideally you would want to curl the piece to get the right radius and then slide it on the spar without making any scratches.
Instead of aluminum you might be able to use a piece of an old plastic bottle. This this would already have the curl in it.
Whatever material you use don't let your tools penetrate though it and touch the spar.
I'm at about the same spot. I thought about leaving those ribs on (and almost did) just as you did, but realized in time. I think you should only have an issue with the rear spar. I was able to fold the rib one way or another to get the front of the rib to come off the spar for trimming.
As far as the back spar is concerned, I like the idea of using a plastic bottle as protection for the spar. I would then see if I could take a ~1" ribbon of heavy grit sand paper and work into the plywood checking the plastic bottle often to make sure that you aren't going through.