Floor puzzle

[Sardine]

I’m doing a shell off renovation on a ’68 Overlander and near to putting the shell back on the frame, but am a puzzled by the amount of variation I’m getting lining up the subfloor to the shell.

When doing the tear-down we marked the seam position of original floor sheets against c-channel and placed cross members at each rib down the length of the shell to stop side-to-side bulging and hold the shell’s form before lifting. We then used the old floor as a router template to cut the new floor. I *thought* this would make it simple to know that the new subfloor was the right size and in the right place.

The C-channel stayed on shell except on the rear banana wrapped corners, where it stayed on the wrap. When we hoisted the shell the skin seemed to be very tightly wrapped around the end corners. It took a fair amount of force from the winch to separate the corners, but that might just have been the Vulkem between the skin sheets.

A couple of weekends ago we loose-fit the floor on the frame and lowered the shell down on top. After much hammering of the sheets and shoving of the shell we got the original marks on the c-channel to line up with the floor seams for the three front sections and two rearmost floor sections, but the section between the wheel-wells was an inch too long to fit, the front wall was pushed forward from the front hold down plate, and the back wall was in the right position but bulging.

This bothered me all week, so this weekend we loose-fit the floor again, this time snug but not pushing out the front or back wall. The marks on the c-channel were consistently forward of the floor seams by about an inch, and about 2 inches would need to be cut off floor section between the wheel wells for it to fit. In both attempts plenty of c-channel rested on the subfloor.

What’s the correct fit? Is it by design that the floor be so tightly wedged in, or was it a bad day for someone at the factory and they just wellied on it till it was in good enough? How was the floor originally assembled in the factory? Am I overly concerned by a 1-2 inch variation in the length of the shell to floor? I would hate to see rivets shearing 5000 miles down the road from getting this wrong.

Thanks for your answers, I know this is a long post.

David

[DryFly]

There's a very good discussion of this very thing on a recent VAP. I think it's episode 191.
I only recently discovered the VAP, after reading something on this forum that mentioned it. It's another great resource we all should help support. I'll be buying some of their DVDs for XMAS.

[Sardine]

Thanks for the pointer to this episode. It has heaps of good information (as they all do). For those interested, my particular question is covered by Ari's question #5, and answered by Colin, about 48 minutes into the episode.

[KCN]

There is a good thread on this by Belegedhel on a 71 GT I think. There are others on it that add their experiences to that thread. Several great ideas. I'm in the same spot right now with my Overlander. Tweaking. I'm listening to the VAP right now, but I'm not really a strong auditory learner and the visual and written answers are useful. Does Ari have a thread on here somewhere?

[Sardine]

So from the bit of researching I did over the holidays it seems that there's as much art as there is engineering in getting everything to line up. From the three loose fits I tried over the last few weeks all the hole markings came within half an inch of each other. I'm pretty comfortable that 1/2 an inch over 23 feet isn't likely to cause too much issue.

[JCPOTTERF]

How did you lift your body off the floor? my 28' ambassador is now gutted the rear floor about 7 ft is removed, I was going to try to splice it in but this forum changed my mind . I really need to pull the trailer out from under the body The question after it's up off the floor whats the most economical way to support it while at rest. i seen a couple of pics on here and remember one holding it up through the windows with 4x4's any help ?

[Sardine]

I sunk four 16ft 4x4s into the ground about 4 feet to make a gantry.You need about 12 ft to raise the shell enough to slide the frame out.

If I had it to do over again (which I've promised my very patient wife and 4 kids won't be until I retire) I'd create gantry's I could move instead of sinking them in the ground so that you can then use the gantry to rotate the chassis.

That being said, while the shell hung from the gantry for the last 6 mo's I didn't worry about it blowing away....

here's a pic ...

[Sardine]

I need a rotisserie for pictures ....

[Sardine]

So I've come to the conclusion it wasn't built that straight in the first place. So after the shell off renovation it went back on straighter than it did in the factory. I wonder if the end caps and interior skins were hand made to fit because they weren't keen on fitting to the now straight shell.

Anyway we've towed 10,000+ miles and no rivets have worked loose yet