Thorp Air Command - T18.net

I recently removed the screws that hold the round plates on the bottom of the S wing which is wet. And the cover is stuck down with pro-seal or other fuel sealant. How in the world do you remove the plate without destroying it?

I've tried going around the edge of the diameter with an awl and tried to get as much seal removed as possible. But it doesn't even move an iota!

Are the plates sacraficial so that once installed you have to cut them out in order to take them off and gain access to the rib bay, and then work to make a new plate and reseal?

I use a thin knife (paring) drive it under the cover, then hold the handle and lightly tap blade around the circle of the cover.

I would try a dental tool that is skinny but has a 90 degree at the end. See if you can get it thru the panel hole but not the flange and give it a tug.
Cubes

I helped build these wings and the only way I have removed the covers is to drive the pointed end of a sharp knife between the cover and ring, holding the knife lightly tap the blade around the cover.

I just repaired an RV-4 fuel tank, and removing th access cover was difficult too. I resorted to using a heat gun to soften the proseal.
I suppose it's UN-necessary to remind all that the tank needs to be fuel free to do this....

_________________
Scott Emery
EAA Chapter 326
T-18 N18TE

Sounds like heat gun AND pointy knife might be the ticket . "Not too hot , not too cold , just right !"

RB

In my particular case. I cannot even get the tip of a ice pic or awl under the edge or even hardely in between the cover and the hole. It seems that the plate was perhaps a little bit larger than it needed to be with such close tolerance.

But I will still keep trying. I'm too stubborn (or is it stupid??) to give up! I need to re-skin the whole wing anyhow. So it is not so much a matter of salvaging. But I would like to keep the skin as intact as I possibly can potentially as a pattern. I also want to salvage as much as possible any part that I can, to minimize what I need to build or replace when reconstructing the wing(s).

Can you perhaps soften the sealant with a heat gun to get it started?

_________________
John Evens
Arvada, Colorado
T-18 N71JE (sold)
Kitfox 7 SS N27JE

I finally got the first cover off! Geeze that was a lot harder than I thought it would be!

I found a tool in my toolbox I had never used before. Looked like a dental instrument but had a very thin flat "blade" on the one end. I was able to "sneek" it under the lip and then with a small ball peen hammer I slowly worked it under and then around the perimeter.

Looking inside I was surprised to see that the wet wing did NOT have any hole or way for the fuel to get to the fuel between the bays at or near what I thought would be the low point. That is at the bottom of the main spar and the nose rib meet. there were a series of I'd say half inch holes staggered but the hole nearest the bottom of the nose rib and the spar was at least half an inch up from the bottom of the skin. Seems like that would trap a lot of fuel in each bay. Or is that the expected way to do it?

I was expecting a small notch in the bottom of the nose rib at the point where it meets the spar. With of course several other holes.

In fact I was was expecting to see a larger hole in the nose rib that maybe I could get my hand through and into the next bay. But all there was I believe was about 4 half inch or so holes in the nose ribs.

Is there any drwaings for a "wet wing" as to how to best construct a new wing?

I'm still don't know whether I will simply replace all the nose ribs and maybe the entire ribs with new as I replace the skins on the repair of these wings.

I'm leaning to just start with 100% all new nose ribs. And try to put in new rivets in between the existing ribs aft of the main spar. I still must replcate accuratly 100% of the holes in the existing main and rear spars. What is the best method to do that?

Do they make a reliable #30 center punch so that it will align perfectly with the existing rivet holes in the spars and with the new skin stretched and held tightly in place, to simply hit the punch with a hammer to mark where to drill each hole after removing the skin and drilling and re-dimpling the skin. Will that be accurate enough for the entire width of the skin along the spars?

I have the wet wings drawings around here somewhere, seemed th have lost my S18 drawings
At one tine I had a spring load center punch that I made a number 40 punch to duplicate holes, One could be made for a 30

I just received a couple weeks ago the S-18 plans from Cubes.

I went through them all but I don't recall seeing the nose rib and wet wing drawing. Maybe they are there. I will have to take a closer look.

NOP...he does not have the wet wing drawings
Jon Walton gave them to Bob and I years ago

Correct. I do not have those drawings.
Cubes

Pretty sure I saw something about "wet wings" in the old NL'S ? Remember I am only right 1/2 of the time .

RB

Hold tight, when I find them I'll make a copy for you