Frame Rot

[monocoque]

Originally Posted by FC7039

I will try to get photos.

The X bracings are 1x2 and the bottom cross is 2x4. The long lengthwise are also 2x4s. They are just screwed into the channels. The picture was taken before the two long boards running lengthwise were put into place. They actually run under the cross 2x4s kind of a strong back if you know what I mean.

Step by step.
1. Put in cross bracing along the floor and screw to the channels

2. Put is more bracing to stabilize the body

3. Using a pry, lift each cross bracing off the frame and slip in a shim (I used pieces of 2x4 laid flat) Work around until the body is now sitting on shims between the frame and the braces. Repeat this until the body is high enough to put in long lengthwise braces (I used 2x4s on end. They will not provide the strength laid flat. You may need to fabricate longer pieces by bolting 2x4s together). As you pry and insert shims the body will flex some.

4. Fasten the lengthwise braces to the cross braces by toe nailing them together

5. In the same process of prying and placing shims, lift the long braces off the frame until you can slide in 4x4 landscape timers. These need to be about 10 foot long.

6. Again in this same process, now using some support outside the frame, I used cinder blocks, lift each corner and shim until high enough to pull the frame out. This can be done with two people, one lifting the 4x4 and the other inserting the shim. I used a jack by myself.

7. Quickly and carefully pull the frame out and lower the body. It looks very precarious sitting up high. If it should have fallen, who knows the damage that would have been done, not to say the crying.

This detail sure helps me visualize the process. At least at this point in my thinking I plan on leaving two sheets of flooring attached to the shell this would substitute, I think, for at least part of your 2X4 cross-bracing. I could always add a few 2x4 if the plywood floor doesn't provide enough cross support. Cross bracing to support the upper shell could be toe nailed into the flooring.

Hopefully one man alone can lift a corner, or section of the shell, to insert shims between the frame and the plywood/2X4 bracing --even though my trailer is 29 feet and weighs more than yours. (I think I'll remove the A/C to shed even more weight). I'll definitely put in length wise braces underneath the flooring for added support AND so the lower skins and floor channel clear the ground. The 4X4 timbers and the cinder blocks are a good idea too.

At this point raising and lowering the shell is the main thing. I need to be able to eventually lower the shell back to near the ground either by slowerly removing shims are gradually lowering with a jack. What kind of jack(s) did you use?

Your right about the shell being precarious sitting up there on cinder blocks. This would be the be-extra-careful-zone especially during the process of pulling out the frame! I'm picturing a carefully balanced house of cards! Definitely something to do on a windless day.

[FC7039]

I used an standard 2 ton hydraulic jack. The kind that pushes up a post. I had a stack of cinder blocks next to each stack that would hold the 4x4. I jacked a little, put in a shim, moved around until I had enough shims to add another bloc

[malconium]

Before I forget to mention it you can buy new inner wheel well shells from Inland RV.

Mostly I want to comment on how you might support the body. I replaced my floor and did some relatively minor frame repair with the body in place so I did not lift the body entirely off of the frame. However the technique that I used I think could be adapted to work for what you need. First of all let me remind you that you may not be able to just sit the body back down on the frame after installing the flooring on the frame. Your year of trailer probably has the c-channel on the bottom of the u-channel at the base of the walls. I am sure you can tell if this is the case given how much of the floor you have already taken out. The c-channel part may not be included around the cureved ends of the u-channel though. OK so what I am getting at is that you may need to lower the body back on to the frame and then install the flooring. If so your situation might not be all that different than mine from a lifting point of view. If you refer to the photo that I have included you can get a pretty good idea of what I did as follows:

1.) Cut 2x4's to the right dimension to go from side to side of the body right up to the inside of the outer skin.

2.) Cut shorter 2x4 legs and added 1/4" plywood gussets to the tops of them so that they can be attached to the 2x4 cross pieces. The idea here is that the 2x4 cross members are enough above the floor surface that I can insert a small hydralic jack to lift at any point that I want to.

3.) Cut some 3/4" squares of plywood about 4" x 4" that can be used as shims under the 2x4 legs for places where the plywood floor has been removed.

4.) I attached the 2x4 legs to the cross pieces and then attached the cross pieces to the vertical frame members using screws through the vertical member into the 2x4 cross member. I uses something like 1-1/4" pan head screws about 1/8" in diameter and two per 2x4 end.

5. You will notice that you do not have vertical frame members that go all the way to the floor at each location. The help support the body at all the vertical members I used 5/8" plywood strips about 6"or so wide as lengthwise members sitting on top of the 2x4 cross members. I used self drilling/tapping sheet metal screws to attach them to the vertical frame members.

6.) Since you are going to remove the frame from under the shell I would suggest using some 1x2 strips diagonally from side to side. Attach them to the top of the 2x4 cross members. This will help keep the shell straight.

7.) OK now you are ready to lift. You should be able to place a small hydraulic jack under the middle of a 2x4 cross member near one end and sitting on either the plywood subfloor or a piece of plywood sitting on the frame. I would think that an old fashioned car bumper jack would work just fine too. Also a smaller size hydraulic floor jack would work nicely. By the way one of these works just great for dropping axles.

8.) On my unit I have two access hatches in the back area that are directly opposite each other. Near the front the refrigerator access hatch is nearly directly oposite the entry door. I would consider putting a 4x6 through these openings from side to side on edge with perhaps 2' sticking out on each side. You should be able to attach them to your other framework at least at the plywood strips. You can also add a little extra bracing if needed to attach them solidly enough. You could then jack the body up so that it is above the frame far enough to get the frame out and rest the ends of the 4x6 on whatever you like. Depending on what type of jack you have available you could also jack up the ends of the 4x6 one at a time. I would think you would get a more evenly distributed lift by lifting from in the middle though. If you do not have conveniently located access hatches I suppose that you could lift the body a little higher and put your cross pieces under the edge of the body. Another alternative would be to put your cross pieces from side to side through opposite windows and attach to the framwork below with cable or chain. I believe that I read of one person in the forum here that lifted their body off from above using a chain hoist to overhead beams through the ceiling vent openings so there are a lot ways that could work.

9.) Once the frame is out you could easily enough lower the body down and sit it almost on the ground if you like. If you have it on a paved driveway you might need to hold it down with sand bags or the like. If it is on a dirt area you could even set 4x4 posts into the ground at each corner and attach the 4x6 cross members to them.

In general you would reverse the process to put the frame back in place. The vertical legs and shims allow you to put the plywood back in one sheet at a time with the body sitting in place. Just take out the shims a few at a time as you put the floor sheets back in. I used a racheting luggage strap to help pull the body into correct alingment with the frame as I was putting my flooring back in place. The curved end sheets can be put back in from inside if you lay them on the frame in a diagonal position and turn them into position. Of course you have to do this before you put in the sheet that is next to the end sheet. Also if you keep the body pretty well aligned with the frame (before take it off) you can use it to trace a template for the curve that is missing on your plywood end sheets onto cardboard or thin plywood.

A little note about the weight. My unit is a 73 31' unit. Its factory rated GVW wet is 7200 lbs. Dry it is probably more like 4000 lbs. The two axles together all by themselves weigh in at maybe 4 or 500 lbs. If you think about all the weight of the things that you will not be lifting with the body you can get a general idea of how much it will weigh. I would suprised if you will be lifting more than maybe 1500 to 2000 lbs total. That is really not all that much compared to jacking up a 4000 lb car for example.

I hope all these ramblings are of some help to someone...

Malcolm

[FC7039]

Here a few pictures, they probably do not much help. I had said I put the long 2x4s on end, but I see they are laying flat. There is also junk piled in there cluttering the picture. Also a picture showing that the braces are simply screwed throught the channel. And one of the jack I used.

[monocoque]

Originally Posted by malconium

If you have it on a paved driveway you might need to hold it down with sand bags or the like. If it is on a dirt area you could even set 4x4 posts into the ground at each corner and attach the 4x6 cross members to them.


Malcolm

Cheers to everybody who has contributed to the topic of supporting, framing and lifting the shell! This has definitely given me some foresight into what lies ahead. Malcolm, I really like the idea of using sandbags. I had planned on installing expansion bolts in the driveway and using climbing hangers to hold the shell down but using bags seems a lot easier and no permenant harm to the driveway.

[monocoque]

The black water tank is out and I can now inspect the extent of the rust from inside the frame behind the tank curbside and roadside. The roadside is okay. However, the damage continues on the curb-side side of the frame. Also note damage to the rearward curb-side tank support bracket (fuzzy photo) at the weld point to the frame. Nevertheless it's nice to have the tank down and a step closer to a complete inspection. The tank appears to be in good condition except for the valve which was stuck in the open position.

[monocoque]

Now I'm at a point in the dismantle just aft of the rear most axle behind the grey water tank. The curbside damage continues here too. This is the area inside the frame but behind the rear most area of the axle mount plate at the point where it is welded to the outside of the frame. Looking from the exterior of the frame it is possible to see where the frame has rotted through the round holes in the axle plate. I'm not sure why these round holes exist in the axle plate. Perhaps to save weight or give more weld points. However in any case the light shining through the frame in the photos is shining through those holes in the axle plate on the other side of the frame. The roadside of the frame is okay. Still has the original black paint! The curbside obviously must have been facing the Gulf of Mexico!

[monocoque]

Here's another look at the same curbside damage seen in post no. 67 above from a point between the two cross members that seperate the black and grey tanks. Also another look at the curbside frame behind the black water tank. Notice I have left a section of plywood in above this area of the frame to support the shell during removal.

[monocoque]

Originally Posted by malconium

A little note about the weight. My unit is a 73 31' unit. Its factory rated GVW wet is 7200 lbs. Dry it is probably more like 4000 lbs. The two axles together all by themselves weigh in at maybe 4 or 500 lbs. If you think about all the weight of the things that you will not be lifting with the body you can get a general idea of how much it will weigh. I would suprised if you will be lifting more than maybe 1500 to 2000 lbs total. That is really not all that much compared to jacking up a 4000 lb car for example.

I hope all these ramblings are of some help to someone...

Malcolm

Malcolm thanks for your ramblings! Concerning weight of the shell. I agree. With the interior assemblies stripped and the AC removed the shell should be relatively light. Here's one of those old airstream photos that show two factory guys actually carrying a stripped frame. Of course I don't plan to remove 100% of the interior skins but the weight should be very close.

[byamcaravanner]

Originally Posted by monocoque

With the interior assemblies stripped and the AC removed the shell should be relatively light.

Todd,

The complete shell with windows and without A/C for your length trailer weighs about 875lbs. Remove the inside skin and you can deduct about 300lbs. This still leaves nearly 600lbs. The shell in the picture is missing the windows, wiring, the inside skin and quite a bit of the exterior skin.

[monocoque]

Originally Posted by byamcaravanner

Todd,

The complete shell with windows and without A/C for your length trailer weighs about 875lbs. Remove the inside skin and you can deduct about 300lbs. This still leaves nearly 600lbs. The shell in the picture is missing the windows, wiring, the inside skin and quite a bit of the exterior skin.

As some have suggested, then, and even adding the wooden frame, the shell should be manageable. Thanks!

[monocoque]

The flooring is out now between the axles and here, at least, there is no damage, either between the curbside or the roadside. So most of the damage, so far, is on the curbside. Extending curbside from the back up to the just behind the axle. There is some damage roadside extending only a few feet forward of the rearmost cross-member. The first photo is curbside, the second photo is roadside. Note the damage curbside aft of the rear axle.

I wasn't expecting the condition to be this good at the axles. However, given even this bit of good news I still don't think there is any chance of salvaging/repairing this frame?

[monocoque]

I've been removing floor bolts the most difficult way possible. I've been using an angle grinder to grind off the heads. This creates a lot of smoke and during the process requires wearing safety glasses and a particle mask. Usually my eyes are watering and I'm holding my breath to avoid inhaling the smoke created by the grinder contacting the wooden floor. A friend watching this process suggested that I get a 1/2 drill, one with a lot of torque, and back these phillips head self tapping bolts out mechanically. Somewhere I read that these floor bolts are bent back under the frame but I have found most of them unbent. I've tried to back these out by hand but the majority of them are frozen tight. Is there an easier way?

[Wabbiteer]

I had no problem backing my floor bolts out with a 1/2" drill geared well for good torque - I did have a 3/8" socket drive Phillips on an eighteen inch breaker bar to persuade them, a turn or two out then back in to let the drill have some time to get up RPMs; but most of them came out on the drill alone. It's all muscle memory.

The leverage advantage on the machine thread screws really doesn't care if the screw shaft is bent as little as they usually are when enough force is properly applied.

[C Johnson]

Originally Posted by monocoque

I've been removing floor bolts the most difficult way possible. I've been using an angle grinder to grind off the heads. This creates a lot of smoke and during the process requires wearing safety glasses and a particle mask. Usually my eyes are watering and I'm holding my breath to avoid inhaling the smoke created by the grinder contacting the wooden floor. A friend watching this process suggested that I get a 1/2 drill, one with a lot of torque, and back these phillips head self tapping bolts out mechanically. Somewhere I read that these floor bolts are bent back under the frame but I have found most of them unbent. I've tried to back these out by hand but the majority of them are frozen tight. Is there an easier way?

I have seen people use a hole saw to cut around the bolt heads. You cut around the bolt heads, remove the floor and grind/cut the heads off after you have 99% of the floor out.

I had bolts. Yes they were bent over underneath. I laid under the trailer and broke them off with a wrench and a breaker bar. On the ones that I couldn't remove that way, I cut them off with a grinder equipped with a cutting wheel.

[byamcaravanner]

Originally Posted by monocoque

I've tried to back these out by hand but the majority of them are frozen tight. Is there an easier way?

Todd,

Very good explanation on the "grinder method." I can feel my eyes water and my nose burn as I recall trying that one myself. LOL!

What ultimately worked the best for me was to use a real long fine tooth blade in my Sawzall and cut the bolts off in the space between the top of the frame and the bottom of the floor. The compressed isulation allowed me to work the blade into that space.

[byamcaravanner]

Originally Posted by monocoque

As some have suggested, then, and even adding the wooden frame, the shell should be manageable. Thanks!

Manageable?...definately! Carried off by two guys? I don't think so.

If you figure out a way to have it lifted by hand make sure to post pictures. LOTS of folks here would get a kick out of that photo. Those re-inactments of historical Airstream events are cool.

[monocoque]

Originally Posted by byamcaravanner

Manageable?...definately! Carried off by two guys? I don't think so.

If you figure out a way to have it lifted by hand make sure to post pictures. LOTS of folks here would get a kick out of that photo. Those re-inactments of historical Airstream events are cool.

Steve, if I manage to recreate such a stunt I'll definitely get pictures and share them here! Now you've really got me thinkin!

[Gkiesel]

Steve has the right idea, a Sawzall works very well in these instances. George.

[monocoque]

Originally Posted by Gkiesel

Steve has the right idea, a Sawzall works very well in these instances. George.

Steve & George, help me out here. I'm not picturing how this would work. In order for this to happen the floor would need to be removed close enough to the screw to allow the saw blade to slide underneath the flooring and above the frame. So, correct me if I'm wrong, the floor, then, isn't being removed in sheets but instead is being cut out piece-meal to make room for the saw? In my case, grinding down the screw-head gives the advantage of allowing the flooring to be removed in basically whole sheets?