Fixing tail sag and a broken frame “in a pinch”.

[Eagle & Bear]

Cannot imbed images into the text so please look at the photos at the end of the post.

Last fall I discovered that my 1976, 29’ rear bath Airstream had begun to develop “tail sag” and that the rear separation repair we paid for two years ago failed. Since we are full timing, I contacted one of the local repair shops and got an estimate. The estimate included the welding and two Airstream frame repair plates. Two weeks later I attempted to set up a date to have the frame repaired but the manager of the local shop just “disappeared”. I called and emailed him. When I went to the shop to talk to him the staff would only say that they did not know where he was. Since there was no one else in the area who could work on Airstreams, I was forced to do the repair myself.

A week after discovering the distortion of the axle mounting plates (bulging outward at the rear axle shock mounts) I ran a 6 foot length of 7/16 all thread from one axle mounting plate to the other and began a process of tightening the two 1” long nuts every other day with enough torque to bend the axle mounting plates back into their original shape. This process took approximately 2 weeks.

I am open to many experiences in life but I will do whatever it takes to keep from being crushed. The frame repair strategy required me to jack up the trailer, use 4 jack stands (rated at 3 tons each) to support two 4X6s placed under the frame and remove the rear axle. Since I did not have a garage to work in or any way to build a scaffolding I wanted to leave the front axle and wheels on the AS for safety. Two scissors jacks were used to support the frame near the rear bumper and 2X4 cribbing was placed around each of the jack stands.

The repair I planned to do was similar to what the AS repair shop had proposed but did not include the AS factory frame repair/strengthening plates. A local metal supply business sold pieces of 3/16” plate steel and, for a small fee, would cut the plate steel to my specs with a torch. Using a large piece of cardboard I drew a template for the repair plate and cut it so that I could put the plate into place without removing the front tire (photo below). It was important to shape the plate so that it would drop in over the shock mount and both axles without getting hung up on them.

A local fabrication shop owner agreed to bring a portable “stick” welder over to where we had parked the AS. It took him an hour to cut several small metal plates, drive to where we were parked and two hours to complete the welding. To save the $344, I might have attempted to do the welding myself but I did not want to risk burning through the thin, 18 gauge frame.

Using a 1 ½ inch wide wood chisel I cut the belly pan to create openings that would allow access to the inside of the frame. I bent the belly pan upward so that it would protect the flooring from whatever heat the welding would create. Though a little rough, the welding looked adequate. Unfortunately, the heat from the welding caused the axle mounting plate to distort outward to its prior position.

I found out that some pawn shops sell nice tools. One of the nearby pawn shops had a Craftsman drill press for $80. Their policy allowed me to return the drill press in 30 days and pay only $20 for its use. I also picked up a good angle grinder but I will keep that for polishing the AS.

Using the drill press, I drilled out three 5/8 inch holes for the axle mounting bolts and 22 - 3/8 inch holes in each of the 3/16 inch frame repair plates. In addition, I used a piece of 24 inch long 3 inch channel to strengthen the back third of the axle mounting plate. If you attempt to do this, drill the holes in the areas between the punched out pieces on the axle mounting plate. With the frame repair plates clamped in place, begin hand drilling the holes into the axle mounting plate and frame. If there is any distortion in the axle mounting plate, drill the 6 to 8 holes that penetrate and surround the distortion and bolt the repair plate in place before drilling the other holes. This will eliminate the problem of trying to align the rest of the holes when the repair plate bends over the axle mounting plate.

This requires a lot of work and, depending on how much time you have, will take from 4 days to two weeks to complete. Purchase 6 - 5/8 inch by 1 ½ inch long grade 8 fine thread bolts, nuts and washers (for the axles); 48 – 3/8 inch grade 8 fine thread bolts (length depending on your needs), nuts and washers for the repair plate; one 5/8 inch bit; and at least 4 – 3/8 inch bits. Consider using 3in1 oil to lubricate the drill bit. Use several pieces of 2X4 material cut to different lengths to brace the drill as it will “catch” and possibly rip your hand off (JK) as it passes through the plates.

In this design, the 3 inch channel will be used to mount a grey water tank just behind the rear axle. It also provides a solid point that I can use for a safe perch (note the piece of 4 inch angle bolted to the channel) for a jack. One of the photos shows a jack under the angle iron perch.

To complete the tail sag and rear separation repairs I am planning to remove the rear banana wraps, the lower quarter panels (exterior) and cut relatively large holes in the interior quarter panels so that I can have full access to the area under the bathroom sink. Once I have the rear compartment and frame almost completely exposed I will repair the aluminum channel material, replace the wood flooring, add reinforcing plates over the floor, attach four outriggers and bolt/rivet all of it together. While inside, I will also replace the original copper with PEX.

Sorry about the arrangement of photos - system decided that it would size and place them without my help.

[TG Twinkie]

Boy that looks like a lot of work. My first question is. Why didn't you just roll the trailer up on blocks under the tires of the front axle? Or did you remove both axles to install the new plates?
I replaced both axles on my '74 Argosy without using jacks. Other than to lower the old and raise the new axles in place.

[Eagle & Bear]

TG: We are full timing. To create a solid, stable platform to work under I had to raise the AS 2-3 inches. I lowered the tonghe jack about 4-5 inches, set up two jack stands near the factory jack points in the rear, laid a 4X6 tranversly under the AS frame and on top of the jack stands and then used the tongue jack to raise the front of the trailer. This transferred much of the weight to the 4X6 in the rear. Next I placed a second set of jack stands and a 4X6 just behind the water tank and lowered the tongue jack so that most of the AS weight rested on the two 4X6s.