Broke out the C-Frame dimpler today. Haven't seen my buddy for months since the elevator skins.

Started dimpling the skins of the left fuel tank. It is important here NOT to dimple the long line on the aft side where the baffle will attach. These will be machine countersunk.

I borrowed some special fuel tank dimple dies from Hugo. These can be bought at Cleveland tools and they produce a bit of a deeper dimple then the regular 3/32" dimples do. Guess this is to compensate for the thin proseal  layer under the rivet head.

Whack away !

Jacques came by to help with the ones near the bend as it's difficult to keep the skin open by yourself.

Then we installed the fuel drain valve plate. This comes pre-drilled in the kit and pre-countersunk. Yeah ! thanks Vans (for once :) )

I just ran a unibit in there to open the hole a fraction of a mm. Not really necessary I guess as the drain plug won't screw that deep anyway.

Then positioned the drain valve plate on the bottom side skin. Just make sure to check from the back that the per-cut hole in the skin is nicely centered over the plate. Then clamped it.

Drilled one hole and clecoed. And then more drilling and clecoes as you go through all holes.

The final result looks like this with the plate removed and the holes deburred. NO dimpling here... remember, the drain plate is already countersunk.

Another view of the finished dimpling on the fuel tank skin.

In preparation for the next work session, I took the inboard rib and experimented a bit with the access plate components. Drawn a hole on the inside radius of the reinforcement ring.
Guess next step is to drill out the opening using the flycutter.