Shell on shell off? Newbie

[Dustycowgirl]

Can y'all please explain the difference btwn shell on repair and off. I have seen a lot of posts about shell off and read a few just not sure about what shell on entails. My project is pretty new all I've done is clean it. It has already been gutted except the bathroom. The only place I can see floor root is in the bathroom. There is also a piece of belly pan? (I think that's the right term) that is unattached at the rear don't have any specific pics of it but will upload some ASAP. Just trying to read up now. Any help greatly appreciated

[RM66caravel]

Welcome and yes a picture will save us a thousand words! The shell off is used by some when the frame requires a lot of work and welding. Taking the shell off is not always needed because you can do a lot with the frame on and if you are limited on space then you kinda have to go with what works for you. Hope that this helps, the belly pan (skin or aluminum on the bottom or under the trailer) can be opened in the back area by drilling out the rivets and you can get a look at the frame.
Cliff

[Belegedhel]

Shell-off suggests that you are physically lifting the entire shell off of the frame and floor. This is typically called for if there is so much rot in the floor that the entire floor needs to be replaced, or the frame is so heavily damaged that it can't reasonably be repaired without removing the floor from it (in these cases, the floor is usually toast as well).

If you only have rot in the last sheet of plywood, and your frame does not require a lot of repair, then you can probably either patch the rot, or replace only the last sheet, without removing the shell. The difficulty is in that the plywood is sandwiched between the frame and the shell, so replacing a sheet with the shell on can get awkward.

good luck!

[Dustycowgirl]

If you do not take the whole shell off how do you get the new floor up under the sides as it's suppose to go. Can you lift only that part ?

[RM66caravel]

No but then you do not really need to if only replacing the rear sheet of plywood then cut the bolts holding the c channel but leave the rivets for the shell in this will separate the floor in that area from the frame then when you slide the replacement piece in you can bolt the channel to the new floor from under the airstream.
Cliff


Yes I said that! Or did I?

[Stefrobrts]

I did a shell-on replacement of the front half of the floor in my Caravel, with the bellypan in place. I cut out the floor in pieces until I had access to reach under and cut through the bolts holding it to the frame. Once the frame was visible we found several broken welds and had a welder come in and fix those. Then I fitted new sheets of marine grade plywood, cutting them so there was an extra seam in the middle, which allowed me to slide them into place under the C-channel. Some people think this is a bad idea but it has been fine for ten years now (I did this in 2004). I then screwed the floor to the frame using self tapping screws from above, and fastened the C-channel to the new wood also using self tapping screws from above.

If you are replacing all the floor, and already have it gutted, you might as well lift the shell. If you are only replacing a portion of the floor, then I think a shell-on replacement is a good alternative to taking it completely apart.

[Dustycowgirl]

The whole shell off idea just kinda scares me still but I'm afraid if I don't of shell off I may miss something. You never know what's under there. I can tell it has spray foam and see the top of one beam. Wasn't sure they even had that in 1968 and I'm pretty sure the floors still original Bc it has bolts and no sign of any repairs

[Stefrobrts]

You are correct that the underside of the floor is insulated with spray foam. That is original.

How bad is your floor? Is there a lot of rot/soft spots? Mine had holes clear through it, and spots where I could just pull away chunks of soft wood with my hand. Clearly all that needed to be cut away back to solid wood. There were probably some minor soft spots in the back under the bathroom, but I couldn't find anything significant after poking around (literally poking, with a screwdriver looking for soft spots), so I chose to leave it alone.

Only you can decide how bad it is. I struggled with the idea that I would be missing something and have to go back and fix it later. If your trailer is already apart, it would be the time to do it, but you also don't want to make extra work for no reason.

[RM66caravel]

Okay please take some pictures we need to see what you are referring to. Sounds like a po did a shade tree insulation attempt.
Cliff



Yes I said that! Or did I?

[RM66caravel]

Spray foam is NOT original fiberglass bat is what they used so time to look in the belly pan!
Cliff


Yes I said that! Or did I?

[Dustycowgirl]

Front near first window appears to have some
Kind of spray foam ATTACH]216372[/ATTACH]

Bathroom floor

[Dustycowgirl]

Second pic shows foam didn't upload in the right order

[ALUMINUMINUM]

Stefrobrts is correct.

Remarkably, for an untold reason, 1968 was the year they sprayed the underside with foam instead of using fiberglass batting.

Go figure??

[Dustycowgirl]

Interesting... Guess I gotta get all that out to see and inspect the frame. I am currently in the process of taking off rivets to detach the belly pan to see what I've got the belly pan is in good shape except the very back piece I'll need to replace that piece.

[slowmover]

Originally Posted by ALUMINUMINUM

Stefrobrts is correct.

Remarkably, for an untold reason, 1968 was the year they sprayed the underside with foam instead of using fiberglass batting.

Go figure??

Avion and Streamline were both starting to replace batting with complete spray foam that year. See sales brochures at Dr Gradeless and Tom Patterson respectively.

This is also a point in time where inflation due to Vietn War was taking off. Tends to mark end of innovation, overall.

[64airstream]

Dustycg,

I'm interested in what you ultimately decided to do. We're just starting on our 68 Overlander. We have a soft spot in exactly the same spot (both sides), but not rotted through. We're leaning toward replacing the front piece of flooring without removing the shell. So far the rest of our floor looks very solid (although, I still need to pull the refrigerator and have a look under it).

Thanks,

Roy and Marie

[gdod25]

Take a 16 penny nail, ice pick, or something similar to check floor under windows and at the entry door of your trailer to help determine how much floor needs replaced. The bathroom is obvious and perhaps your frame is heavily rusted?

[luca16]

I'm thinking about no shell off complete floor replacement hypothesis.I'm going to explain my project, First step cut first floor 2'square width side to side off.Second round built up a small size steel ribbon right lenght sliding it below c-channel from that to the opposite,90 degrees respect the longitudinal structural frame's bars. The ends of the bar fitted with holes for screwing and teflon covering preventing corrosion from c-channel and screw contact. Put the ribbon in place screwing throught the teflon in the hole fixing it to the c-channels like a bridge, then weld the ribbon to the frame. Repeat step by step first and second round along the surface. At the end of the process the floor is off with shell in place with good stability. Now the floor will be just replaced as you want with any structural impact and a solid support. Hoping in my scolastic foreign llanguage I thank in advance for any relplies.

Luca

[luca16]

I'm just starting with my own project. Now here is first round, look at shots attached below, I hope are clearer than I wrote previously. You can see bars' feature and how I've fixed th them down there on the frame and below the c channel. Even a stiffener for shell's periferhal edge . Weldering is going on. To be continued...

Luca

[luca16]

Originally Posted by luca16

I'm just starting with my own project. Now here is first round, look at shots attached below, I hope are clearer than I wrote previously. You can see bars' feature and how I've fixed th them down there on the frame and below the c channel. Even a stiffener for shell's periferhal edge . Weldering is going on. To be continued...

Luca

First welderings done. Now the frame is just plugged with the rear.Small inferior inner skins' patches for vertical c channel screwing were removed and will be replaced in the and. Another old subfloor's square cutted off. 2nd bar in place is going to be attached. My job is running quickly...

Luca

PS please rotate some pics I don’t know the reason why not be able to do