Fuel tank ribs

Fracrat · #1 02-26-2013, 04:42 AM

I'm having a devil of a time with fitting the ribs. The bend of the skin does not seem to be enough for the rib. Having to force the skin to mate up with rib holes. As much as 3/8 in alignment difference. As always thanks for the help!

rleffler · #2 02-26-2013, 06:39 AM

Which ribs are you having difficulty with?

The tank ribs were the ones that I had the most difficulty with, but then I figured out a solution. I had started by putting clecos on one side, then having problems with the other side. I had symptoms like you described. I found if I reversed the process and started on the other side, the process went smoother. I can't explain the physics, only the results.

There are other rib "opportunities" in the build too. If you haven't read the "gotchas" section that Tim Olson put on myrv10.com, I would strongly recommend it.

bob

bill@fusion4.net · #3 02-26-2013, 06:45 AM

I found them difficult as well, but found if I clecoed starting at the tip on both sides that they aligned better. They were very tight

Fracrat · #4 02-26-2013, 06:56 AM

Thanks for the feedback will try a different technique. will also read tim olsen's site. hopefully just need a little more elbow grease. trying not to be to ruff with it.

J Twilbeck · #5 02-26-2013, 09:02 AM

I found these difficult as well. After arguing with them for longer than I would like to admit I found that if I cleco the leading edge in place on each side (a single hole on each side) and then keep alternating sides as I move aft it worked out with no problems.

ppilotmike · #6 02-26-2013, 09:53 AM

My fuel tank ribs were also a challenge to assemble and match drill. I fluted them as best as possible to align the holes, but they were still a royal pain, especially the holes near the rib tips.

BigD · #7 02-26-2013, 10:00 AM

Almost done with my tanks (rear baffle remains) and I agree with Twilbeck and Bill. I left the skin out of the cradle to start, then clecoed one rib at a time, bottom leading edge, then top leading edge. by having the skin out of the cradle you can open it up a little and get the clecoes started. With only two holes clecoed, they are a little bit floppy. Then get the next one or two per side in and finally put the thing in the cradle. Still required some pulling with a punch to get some of the holes lined up, but more like a 1/16th of an inch. After they are drilled and dimpled, the pro seal plus the slightly larger holes allow assembly with the skin starting in the cradle. There have been some recent posts on this as well...

==dave==
RV-10
ordering fuse

Mouser · #8 02-27-2013, 07:25 AM

I concur with what has been said above. I'm about to put the aft baffle on my final tank. Getting the initial assembly done was a real pain and I ended up with a lot of scratches on the inside of the skins near the nose of each rib. I did find after match-drilling that the second assembly was considerably easier.

longranger · #9 02-27-2013, 10:04 AM

The -7 tank ribs were no piece of cake either. After a lot of trial and error, I got the best results from starting on top at the nose, and working my way toward the spar, then put the half-clecoed tank in the cradle to compress the skin toward the bottom side, then clecoed the bottom starting at the spar and working down. The first cleco or two on the bottom need to be levered into place, but after that it gets easier. Details and photos here.

Fracrat · #10 03-01-2013, 08:00 PM

Changed my technique and started at the nose out of the cradle and put first two clecoes on both sides then worked my way aft. Still a pain but worked. Thanks for all the help.