1962 Ambassador Restoration – One Bite at a Time

[66Overlander]

Originally Posted by dbj216

I think 62 was the first year of the dura-torque axles, and maybe the frame rail design change was part of that major upgrade over leaf springs.

The switch to the Duratorque axles occured for the 1961 model year.

I believe that 1962 was advertised as the first year for the new "aerostress" chassis, but in reality I have no idea what that means. Maybe that is when they added the oval holes for lightening in the cross members and outriggers. I know my 1962 Safari has those, but my 1955 Safari did not.

[steinVT]

Joe, I think I can help you with Aerostress Chassis. The main frame rails in the newer chassis are built from 4" structural steel channel (U shaped with 1 1/2" legs) instead of 4" x 2" rectangular tubing like on my Safari. This is an improvement in that water cannot get trapped and corrode. Except in the front A-frame and the rear six inches or so, where they welded on a 4" plate to make a box. The factory did not seal the weather ends of the boxes, so dirt and water can collect in the tube.

I just discovered that is exactly what happened to my chassis. I was cleaning it getting ready to repair and paint, when I noticed a different sound as I was tapping with a body hammer. I got a little more aggressive and an area that looked perfect from the outside, really was pretty bad.

This is what I found:

Then tapping on the other side, the same thing.

A little scary since I had just dragged it 300 miles home.

The rest of the main frame is fine, but because of some pitting corrosion, I will replace the front 5' and the coupler. - Mark

[66Overlander]

Originally Posted by steinVT

Joe, I think I can help you with Aerostress Chassis. The main frame rails in the newer chassis are built from 4" structural steel channel (U shaped with 1 1/2" legs) instead of 4" x 2" rectangular tubing like on my Safari. This is an improvement in that water cannot get trapped and corrode. Except in the front A-frame and the rear six inches or so, where they welded on a 4" plate to make a box. The factory did not seal the weather ends of the boxes, so dirt and water can collect in the tube.

I just discovered that is exactly what happened to my chassis. I was cleaning it getting ready to repair and paint, when I noticed a different sound as I was tapping with a body hammer. I got a little more aggressive and an area that looked perfect from the outside, really was pretty bad.

This is what I found:
Attachment 366805
Then tapping on the other side, the same thing.
Attachment 366806
A little scary since I had just dragged it 300 miles home.

The rest of the main frame is fine, but because of some pitting corrosion, I will replace the front 5' and the coupler. - Mark

My previously owned 1955 22' Safari had the main rails made from 4x2 thin wall tubing (and yes they were significantly weakened by rust), yet I had a friend with a 1956 26' Overlander that had beefier C-channel main rails rather than the rectangular tubing - not sure if that was a 1955 to 1956 difference or a 22' to 26' difference. Both of these were Ohio trailers, California may have been different.

In any case I believe the mainstream switch to the much beefier C-channel frame members occurred before 1962 for most, if not all, Airstreams, though the little 16' Bambi's had rails of a smaller size. I do not know the exact year this change was made, but I believe it occurred before the Airstream started advertising the "aerostress" chassis. I seem to remember they claimed the "aerostress" chassis was lighter, yet stronger than their previous chassis. Perhaps it came about as a result of lessons learned on the 1959-60 African Caravan that had several cases of frames cracking.

Or perhaps there was no real chassis change between 1961 and 1962, but the term "aerostress" was created by the marketing team. A detailed review of likely several 1961 and 1962 frames from both plants would be needed to really determine the answer.

[Scott S]

Joe, this interests me, as my 1960 Overlander has the box frame. Over the years both the front and the rear of the frame where exposed to the weather and have rusted...mostly from the inside out as I have been diligent for the last 30+ years to keep good paint on the frame. These spots have been repaired at least four times and now we no longer use the spare tire rack on the rear bumper for fear that the stress will snap the frame in half between the bumper and where the frame disappears into the underbelly.

Dropping the underbelly reveals a mint looking frame except where it was bent to make the A-frame. That needs repair now too. I think I see a frame off restoration in my future...probably just replace the frame and running gear so I can lose the leaf springs as well as the rust!

Anyone know who does that kind of work? Its a bit beyond my physical abilities.

[dbj216]

As they say: "upon further review". Sometimes, rarely, we find a 50 year old item that is in very good original condition. Most of us don't. Your old Ambassador looks like so many renovation projects in these Forums. I think they call it the slippery slope of vintage projects. My 75 Overlander was a good example. It looked good from the outside. But it failed the bumper bounce test, the axles were like hockey pucks, rusty frame members, broken waste water tanks and many freeze repairs in the plumbing.

Moisture, and trapping of moisture, is the enemy of Airstream trailers that sit outside.

I am confident you will restore this old girl better than new and have fun doing it. Press on regardless.

David

[Cheoah]

Hi Mark, you’re making great progress. I’m going to sound the A again with a hammer, although I know I’ve done it once.

The bunk wall, which is the forward outside wall of hanging closet, is at 65”.

The closet is 24” outside-outside. Leaving 41” from aft inside skin to closet.

What down angle are you using for new axles?

c.

[66Overlander]

Originally Posted by Scott S

Joe, this interests me, as my 1960 Overlander has the box frame. Over the years both the front and the rear of the frame where exposed to the weather and have rusted...mostly from the inside out as I have been diligent for the last 30+ years to keep good paint on the frame. These spots have been repaired at least four times and now we no longer use the spare tire rack on the rear bumper for fear that the stress will snap the frame in half between the bumper and where the frame disappears into the underbelly.

Dropping the underbelly reveals a mint looking frame except where it was bent to make the A-frame. That needs repair now too. I think I see a frame off restoration in my future...probably just replace the frame and running gear so I can lose the leaf springs as well as the rust!

Anyone know who does that kind of work? Its a bit beyond my physical abilities.

Well that is a great data point. I admit to having a feeling that they changed to a C-channel frame before 1962, but not real data. If your 1960 still has the box frame that means the change was made somewhere between a 1960 running change and 1962, when there advertised the Aerostress chassis. Maybe it was 1962 after all. I'll be keeping my eyes open on this detail from now on.

[HiHoAgRV]

Originally Posted by 66Overlander

Well that is a great data point. I admit to having a feeling that they changed to a C-channel frame before 1962, but not real data. If your 1960 still has the box frame that means the change was made somewhere between a 1960 running change and 1962, when there advertised the Aerostress chassis. Maybe it was 1962 after all. I'll be keeping my eyes open on this detail from now on.

I’m pretty sure that my ‘61 Ohio is the same as my ‘63 California Overlander, both are structural C channel, not a box. I’ll double check in a few weeks when we go and see it.

[islandtrader]

Originally Posted by steinVT

Like I said, there was a lot of interior wall corrosion. From letters and postcards found in the trailer, I think it might have had a stint on the beach in Florida. Wonder if the salt contributed. Just glad it stayed away from the frame. Here is a picture of a screw? that I removed from the entryway threshold. - Mark
Attachment 366450

Mark..what I did for the inside corrosion was a simple two for one fix. When we tested all the seams. Using soapy water out side and blowing compressed air inside. I used flex seal on the seams and then painted over the corrosion spots with flex seal (after wire brushing). One brush one product one time...

BTW living in FLA. and living on a barrier island I can safely say yes the salt air has contributed to any and all corrosion in your trailer. If I forget a socket or wrench someplace with in a week it is showing signs of corrosion.

[steinVT]

This was the pile of corrosion that I emptied out of the first 5 feet of the A-frame. Notice the large welding vice grips for perspective. We are talking pounds.


Airstream created the rectangular section of the frame by stitch welding a plate onto the structural channel. Why they didn't close the end and do a continuous weld to keep out the water at the factory I'll never know. It was very short sighted. The new A-frame replacement won't have that problem. All this welding is hidden under the coupler.


This is the replacement section just prior to welding. Kind of a pain to layout, but ended up fitting nicely. The replacement structural channel was the lightest available to me, but is still about 0.045" thicker in the web then the original. A little extra weight for additional strength. I also like the security of the bulldog coupler, so I used the same one as I installed on the Safari.


Still left to do; replace the rear foot or so of the frame rails and add fish plates over the main joints. The rear rails were heavily modified for plumbing feed thru's and I want to extend them an additional 6" so I can build a bumper trunk. I also will be building a spare tire carrier under the A-frame. - Mark

[Bubba L]

Have no idea why the main frame members were left open on the ends on most of that era chassis. I also sealed mine. Colin Hyde has brought that up on several episodes of the VAP. Some have even slid a bit smaller tube inside the 4” main frame member, drilled holes and puddle welded through the main frame onto the added tube. I guess for added strength and less flexion. You sure are doing it first class. Great job.

[Atomic_13]

Great work as usual, Mark. Completely agree on the importance of closing up the rectangular tubing ends. Did the same on my Tradewind.

[dbj216]

My wife's 86 Limited had open A frame square tubes. I was having mouse problems and figured what a great way for the little critters to come on in and roam around the belly area and then up to the interior itself. So I closed them off with an aluminum cap since I don't have a welder. At least less road spray water running down the frame members, but it had little affect on the mouse house.

I've closed off the other trailers I've worked on also. Again, just with a cap.

David

[steinVT]

I've made quite a bit of progress since my last post. The rear 18" or so of the frame was cut up for plumbing pass thru's and were quite corroded also. Instead of replacing with the heavy channel and closing in with a plate, I welded in some 2" x 4" square tubing. This was the same material I built the Safari chassis with. At the same time I extended the rear bumper back another 6" so I can build a bumper trunk for the sewer hose.

From the factory, the bumper is held on by welds directly to the frame. This is not that secure and since I use the bumper as an attachment to my rotisserie, I add an additional bracket on each rail to help support the weight.


The design for the rotisserie was the same as I built for the Safari and I actually used some of the same lumber and the attachment to the coupler. There are some benefits for repeating the process.


This frame is 6 feet longer than the Safari, and heavier, but I can easily spin it by myself and stop it anywhere to work on it. I don't like inverted welding so all my welding is now on the flat. I spin it multiple times during the day. If I am going to be working under it, I always chain it to the tractor bucket as a safety measure. - Mark

[steinVT]

My new axles have arrived. I ordered them through Colin Hyde and went with all of his recommendations. 3500#, 10" drums and 32 degree down angle.

As I did a test fit up, it was immediately obvious that the mounting plates were not going to work. The mounting holes in the plates were 10" apart and the new axles 8". Not only that, but the plates were too short to even accept new holes. The old plates also had swing arm bump stops welded on that were in the way of the new horizontal shocks.


And then on closer examination, I found that corrosion had gotten between the plates and the main frame rail in a big way. Even forcing the two apart in a couple of spots. Colin had warning me about this potential.


Basically I had no choice, the plates had to be replaced. To do that, all of the welds had to be cut. Harbor Freight has a coupon for a package of 10 - 4 1/2" cut off wheels. I went thru more than a few. I found it interesting that since the frame was on the rotisserie, as I cut welds, the plate would pop a bit as it was helping support the weight.

The original plate was about 0.200" thick. I decided to replace it with 0.250" thinking it would replace any strength lost in the frame rails from corrosion. Making the axle cut outs again was a job for the 4 1/2" angle grinder. I hope the grinder makes it through this project. - Mark

[ALUMINUMINUM]

Leafing through the 1968 brochure, I marveled at the mechanism revealed way down in the lower right image.

Thought you rotisserie builders would get a kick out of the AS factory production method of frame flipping.

[islandtrader]

Originally Posted by steinVT

. Harbor Freight has a coupon for a package of 10 - 4 1/2" cut off wheels. I went thru more than a few.
Attachment 368577

I do not use those wheels any more since they have literally exploded on me. I am sure you are wearing a face shield and gloves. If not be fore warned...stay safe.

[dbj216]

It is a lot of work to repair a frame and install new axles. Fabricating a new axle mounting plate is the right way to go considering the corrosion. I just spent most of Saturday installing new axles on my friend's 76 Sovereign. We went with Dexter #11 7000# axles set at 3600#, on the very low limit of these larger axles. They have a 3" square tube. We used a tool by DeWalt called a "porta band", or a power band saw that is portable. It worked well for us. You also gotta figure out shock mount locations, always fun.

Our axles went on at the end game of the project. Yours are going on early as your frame is fully accessible. Just like the Airstream factory does it to this day.

Nothing like a compact tractor to hold things up.

David

[steinVT]

Aluminumum, thanks for that picture. Interesting how they attached to the bumper. Still would scare me to have the complete frame with wheels, hanging from those four 1 1/2" welds. When I took mine apart, they weren't all that great.

Islandtrader, gloves, respirator and safety glasses always. Burning though 15 wheels, I only once had it get away from me. Definitely humbling.

David, I like to get the dirty stuff out of the way. I know you have installed belly pans multiple times with the trailer upright, but I think that would be beyond my patience. And by building the new frame for the Safari, I missed out on all of that fun cleanup with a wire wheel. The frames look pretty big when it's time to clean them up. It does feel good when it's done - Mark

[57Vintage]

X2 on being able to rotate the frame. Working solo it makes so many things easier: welding, painting, conduit, belly pans, tanks, subfloor .....



I'm old enough to be lazy, took the frame to be sand blasted after repairs were done.