Simple trick for installing upper inner skins...

[malconium]

I found that I was having some trouble figuring out how to lift and hold the top inner side skins in place long enough for me to get them secured but I came up with a simple technique that I would like to share here.

On my 1973 31 footer there are 3 levels of side skin and the top one is about 3' wide and close to 22' long. While it is not all that heavy it is pretty floppy. Also, as mentioned elsewhere in a post about installing foil insulation, I decided to use felt strips to provide some amount of thermal isolation between the skin and the body ribs. This makes it hard to see the mounting holes for re-attaching the body panels. It is easy enough to find them with an ice pick if they are close but trying to hold the skin in place and hunt for a hole is pretty hard. My wife and I gave it a try and gave up on just lifting and holding it in place. I didn't want to have to collect a bunch of friends to come help so I gave some thought to how I could hold it in place while I found the mounting holes. First of all let me point out that once I got a few holes located at the ends and a place or two in the middle it was easy to find all the rest with the ice pick.

I had thought about creating some sort of support t-bars or even in investing in some commercially available products like the T_Jack or Third Hand telescoping support poles. I did not want to spend the money for one thing and I just needed a quick simple approach. The way that I decided on cost me about $4 dollars for some bolts and a few pieces of scrap lumber that I already had.

The main premise of the approach is that the body itself has the strength to support the panel when it is in place so why not figure out a way to get the body to help support it temporaily while I fasten it in place. The main steps are outlined as follows and are supported by the attache photos:

1.) I fabricated two simple window brakets (see WindowBracket and WindowBracketTop photos) that set in the window frames of two of my street side windows roughly 6 feet from each end of my wall panel. I used 3/4 inch plywood, some 1/4" plywood and a 3/4" thick strip of wood in the bottom of the window channel to lift the bottom of the bracket. I sized the height so that I could slip the top end behind the window channel and lift it enough to slip the bottom over the bottom channel. When I dropped it in place there was about a 1/4" of the bottom channel to help hold the bottom of the braket in place. The top of the middle piece of plywood is slightly lower than where the bottom edge of the panel attaches (maybe 1/16" or so).

2.) I came up with a simple bracket that I mounted in two places to the middle of my ceiling ribs. The idea is that it the piece of 2x2 can rotate into position to hold the top edge of the panel in place. See the Diagram photo for a detail as to the hardware I used. It is all 1/4" diameter stuff. I drilled one hole in the middle of each of two ribs to put the short bolt through. The 2x2 is long enough to work for putting up the panel on both sides. I cut it to about 26" long. Look at the CeilingBracket photo for an installation detail before putting the skin in place.

3.) The technique also relys on forcing the skin into the aproximate curve that it will be in when placed. I did this using some strapping tape (the kind with fibers in it). I would recommend putting something like a strip of cardboard or some such thing at the panel edge where the tape is since the tape could easily be cut by the metal edge there. I didn't do that and things worked OK but I did have one or two pieces get cut. Look at the SkinTaped photo to see what I mean. The idea here is that the skin panel will be more or less straight and not flopply with it taped this way. I think I taped it in about 5 places. The strapping tape stuck just fine to the back side of the panel.

4.) My wife and I then lifted the panel up and set the bottom edge into the top of the two window brakets. On my end I had to fish some wires through the panel before I set my end in place. We then tipped the panel up at the top and rotated the two ceiling brakets into place. We were then able to let go of the panel. It took all of maybe 5 minutes to lift the panel into place. My wife was able to get back to pruning here rose bushes while I fastened the panel into place.

5.) It was then quite easy to move the panel a little to get some starting holes to align. I used a couple of screws to hold the bottom two ends in place to start with. I then went along the bottom edge and installed rivets there first. One the panel position is well established it was no trouble to finish attaching the rest of the panel.

I will use the technique again for the curbside upper panel when I get to it. I think that I may use 3 window brakets over there - partly because of where my windows are located on that side and partly because I think it would help to have brackets a little closer to the ends of the panel and one in the middle. Just two ceiling mounted brakets seemed fine but it might not hurt to have three of them too. The middle middle body ribs were not all that accessible though because of the air conditioner location.

All said the technique worked quite well and I would recommend it to anyone else that does not have ready access to a bunch of people to help lift their inner panels into place. My next challege will be to see if I can do something similarly simple when I put my center skins back in. Mine are not in a continuous piece though so it might not be all that hard to lift into place. We shall see...

Note: I see that there are no labels directly on the photos. In my view their names do display if I hold my mouse over them. It looks like you can also click on the photo to get a larger view.

Malcolm

[CanoeStream]

Thank you Malcolm! I'm fascinated by jigs and their usefulness. Thank you for posting this.

[SmokelessJoe]

Malcolm, if you do more of this the butyl tape truck body builders use would be perfect to line the ribs before your re-rivet the panels on.

Not only will it act as a non-conducting thermo block, it will sound deaden. It is also very “sticky”, which will help to hold the sheets while you rivet.

You can see it being used here, post #132, in a somewhat similar application:

http://www.airforums.com/forum...-18448-10.html


Sergei

[malconium]

Sergei,

Thanks for the pointer. I had not yet seen that thread. You have some good ideas going there.

Where can I get the butyl tape that you described? Do you have some sort of exact product name or part number? I am not sure if I want the panels to be stuck on though. I have already had to loosen certain parts to make small adjustments. What I would really like is something that had adhesive on just one side.

Malcolm

[Shapmaui]

Malcolm- and all- what an amazing resource this forum is. A post from 2007, helping a guy in 2022!! Like "Back to the future" or some strange star trek time travel technique.. So glad these posts are still available. PLEASE never destroy this resource!

Topic at hand, confusing at first, so I read and re-read it more slowly, looking at each picture, and have a good idea of what you accomplished. I'm just in the process of stripping down my 1973 31' Sovereign- see my thread here... and have a long way to go, but am thinking alot on whether to take the inner skins off or not. The reinstall being so seemingly difficult by so many here...

http://https://www.airforums.com/forums/f186/hasty-mouse-to-mighty-mouse-228156.html