When to dimple wing ribs?

[danielhv]

Ok, so I just glanced ahead in the directions but didn't see anything... I just got through match drilling the ribs to the spars, do I need to match drill the holes in the flange where the skin, spar, and ribs rivet together so that they can be deburred? Also, should I go ahead and final drill/dimple the rib flanges before they are riveted to the spar?

[-goose]

From memory I clecoed the ribs to the front & rear spars, fitted & drilled the skins with everything mounted to the posts & plumbed square. Then removed the ribs, deburred the holes, dimpled and primed everything before riveting them back to the spar.

I think next time though I won't match drill or dimple the rib-skin flanges until after the ribs are all riveted to the spar. Easy enough to spot prime those flanges after the skins are match drilled later on.

[mackd]

Originally Posted by danielhv

Ok, so I just glanced ahead in the directions but didn't see anything... I just got through match drilling the ribs to the spars, do I need to match drill the holes in the flange where the skin, spar, and ribs rivet together so that they can be deburred? Also, should I go ahead and final drill/dimple the rib flanges before they are riveted to the spar?

Wait to drill and dimple the rib flanges (except for the ones that get riveted to the spars). You'll match drill with the skins (and debur/dimple those holes) later in the process.

I don't know what the "correct" thing to do is for those few holes that pass through the skin, main spar flange, and rib flanges, but I waited and drilled them with the skins later. The only thing you won't be able to do is to debur where the rib flange and main spar sit against each other. You could still get a chip chaser in there, at least. Probably not a big deal...