'70 Caravanner restoration

[66Overlander]

Olympics are a clear indication that a panel (or window) was replaced. If you want to switch to bucked rivets, now would be the time, but if the olympics are not leaking, some might advise "don't fix something that ain't broke", so you don't risk creating a leak. I would probably replace them so that the exterior rivet heads would appear as normal. A trained eye can always identify olympics.

Regarding wheel well liners, my 1962 Safari had dual liners with fiberglass insulation in between, but it was a galvanized lower with flange below the floor and a hard fiberglass inner with flange above the floor. If only using a single liner, I'd think you'd want it with the flange below the flooor to keep the edge of the floor (and the interior of the trailer via the seam created) from being exposed to moisture and dirt in the wheel well.

[Wabbiteer]

Yeah, that's a repair, but I'd venture from the picture one done without removing interior (cheapest method) because there isn't two tubes of vulkem sealant slathered over the spread tripod legs since there was no access to them...

From the accuracy of drilling and seeing only a few Olympics partially set from obstructions someone knew what they were doing, not seeing (gross) water leak tracks leading back to them either is a good sign. It's a now-or-never event to replace them.

I can attest that having interior Olympic rivet lines parged over with caulk increases difficulty level from fun to major annoyance to replace with bucked, you and Xylene have already been introduced. To buck in rivets in my case I had to add & clamp interior washers to many as they located over seams, very not pretty. I include photos of lazy olympians that weeped, even siphoned, moisture in past Vulkem generously slathered over them as they were located on multi-layers of sheetmetal.

Those side window frame aluminum extrusions I pictured were soft enough they'd seriously deformed from original & repair riveter force, push too hard on tool and the percussion indents the work piece as well as rivets - I used a plenishing hammer attachment with a few gun strokes to level the serpentine ribbon effect back near flat, the flange had lifted between rivets for an air-gap to exist between frame and shell.

Wheel Tubs: the OEM vacuum formed black plastic is just 3/16" thick at the edges, it is maybe a little over 1/16" thick as stretched to reach the rounded 'top' of their mold which, of course, is where it fatigued and cracked. What I did was trim the inside flange length to fit inside the frame rail and heat-gun soften the front/rear flaps to fit just inside the closed-face outriggers. Right/wrong/indifferent that's what I did.

Photo(s) reveals there is more trimming & fitting to be done, also showing that -15°F overnight weather has snow living in places the sun don't shine. Speaking of cold, apologies for unimaginative photos since the windchill had turned cold to torch burns.

[Jeremy9107]

66Overlander and Wabbiteer your comments strengthen my trepidation both of the Olympics being there and for the difficulty of their replacement. I am not sure which fear is greater though. I have zero experience in riveting and think I will mess something up major if replacing in those tight spots around the window. But also don't want to regret leaving if they start to leak....

Those Olympics are around most of the panels along the front end cap. Wish I new what had happened where it required that extensive of a repair.

Wabbiteer. Like what you did with the wheel tub. That would solve my concern about tucking 1/4" thickness of flange under my floor. Did you glue the front/rear flaps to the outriggers? Not quite understanding how you secured the other flap.

[youngpeck]

Originally Posted by Jeremy9107

I have zero experience in riveting and think I will mess something up major if replacing in those tight spots around the window. But also don't want to regret leaving if they start to leak....

From what pictures I've seen of your restoration I don't think you will have any problem picking up buck riveting. I had never done it and really enjoyed learning how to do it. A little practice helped. I found myself looking for additional projects so I could do more. The resulting rivets all look just fine and are structurally healthy. In several cases I added more rivets along existing rivet lines just for a little extra strength in the body. You will be happy you learned to do it. And your trailer will be happy, too. All you need is a person to be your "bucker."

[Wabbiteer]

If* you replace those Olympic rivets I’d sure go with a serial process of only removing 3 or 5 at a time to keep the seams bound tightly stationary during the process. Bucking rivets is incredibly easy itself so it is the prior proper preparation that leads to grey hairs.

I made up a Plexiglas spacer where an over-length rivet could be inserted from outside and held, then inside worker braces rivet against spacer and uses razor sharp wood chisel and light hammer to trim shank to a perfect length to achieve the recommended mushroom against the bucking bar. That wouldn’t fly in Aerospace industry but for lawn furniture…

Wheel wells: Maybe some extra details required, my tubs had a doubling aluminum shim of .040 between plastic and the shell to better keep the unsupported open well skirt taut. The foil tape shown is just backer to use canned minimum-expansion spray foam as glue/filler, should have top coated it with some paint to keep UV & ozone off it as it’s not aging gracefully.

Both fore & aft plastic flaps simply hang close to the solid-face outriggers, remember no adhesive sticks to polyethylene (PE), the kayak repair compound requires light sanding and using open flame to modify the PE molecular surface film to give some degree of grip. I plan to heat-gun soften those flaps again and add an aluminum clamping strip held by stainless fasteners, tighten it down over some tremco or Sikaflex bedding to keep it insect proof.

The ‘slip between frame & floor’ assembly method allowed moisture intrusion still plainly visible from rust discoloration of the black plastic flap; the closed face outriggers & those compartments were in bad lace-perforation condition.

I wondered if reasons exist for keeping floor loosely pinned above the axles, there are zero floor fasteners attached to ladder frame rails down the entire floor length, so only a few floor-to-spar screws exist near wheel wells lending a degree of ‘articulation’ since that length lacks the extra stiffness of 30” of plywood and pinning to outriggers. We’ve been told the stiff shell construction ‘holds up the frame & axles” so is a softer middle something encouraged by having the slippery PE wafers inserted where the flooring narrows giving the shell a little disconnect from axle plate flex, oscillation or twisting deflection from towing geometry forces?

I think not-so-much in modern times, much earlier Airstreams did a whole lot more unimproved roads with bottoming out dragging & washboard surfaces than what may be encountered these days so I even ended up gluing the entire floor to the frame with a silicone gasket spacer as thermal break & squeak eliminator.

Sorry for droning on and on, I’m looking forward to you sharing closing your trailer up and what directions you choose to proceed from there!

[Jeremy9107]

youngpeck. Hope you are right cause am going to tackle the project of changing out the Olympics. I'm just the kind of guy that 5 years from now will lay awake at night in that thing wondering why I didn't do it.

Wabbiteer. Understand better now. Had same concerns about moisture getting under flap of well when sitting on frame too. Was thinking of using Sikaflex between frame and flap but since you say nothing sticks to PE then prob not a good idea. Thinking of using your install method now.

Interesting thoughts on the flex design. Are you saying you had no elevator bolts holding floor down over axles? I need to look at mine but I believe I do. Certainly lose the stiffness compared to the sections that include outriggers. Can you tell me more about the silicone gasket spacer you used under the floor. Was this something that spanned the entire length of the cross members and outriggers or just something you spaced intermittently?

[Jeremy9107]

Just can't stand the oversprayed Vulkem and insulation glue that trapped dirt, mold, mildew, fiberglass and whatever else on the inside of the outer skin. But holy cow is it hard to remove. Xylene works (so does Goof Off Graffiti remover) but it evaporates within 10-20 seconds and it takes quite a bit of effort with plastic knife, scrub pad, scrub brush and rag to remove completely. Took 1 hour to do the clean section in the photo (from floor to roof). Not sure want to invest time needed to do entire trailer though.

Pros...looks nice (nobody will ever see). will certainly remove bad stuff and smells. maybe gain something in way of reflective property of alum. allows for better surface to adhere when placing insulation.
Cons...tedious, time consuming, messy, vapor inhalation, might compromise seam and rivet seals.
So, do we leave it alone or suck it up and put in the effort?

On another note. Do either of these photos represent corrosion or just grease/grime? Photo 1 is along the center roof line. Photo 2 is skin that wraps under belly. How does one go about halting/removing corrosion?

[Wabbiteer]

Maybe I should cut back on the coffee, I'm yakking up your thread something fierce - guess that means I like what you do, eh?

The discolored aluminum looks like long term humidity-condensation events reacting with the metal - a loop of some trace elements (chlorine, sulfur, salts) building oxide layers that invited repeat condensation... if it ain't adhesive over-spray its now a metal salt if it won't wipe off. Plus maybe some bonus algae, lichen and molds just passing time.

I used an aircraft metal etch paint prep solution and loved the results. http://www.aircraftspruce.com/catalo.../alumiprep.php but beware it needs running water rinsing, also some places want to add $50 hazmat fee, that outfit will put a quart at you door for $30, two for $50.. Yes it contains a tiny kicker amount of Hydrogen fluoride (hydrofluoric acid) so it can't touch bare skin or be smelled/tasted no how now way but it works niiiice... Dilute down to 1:4 or 1:5 and a $10 walmart garden pump sprayer and you've got new aluminum... if it isn't adhesive overspray.

. ..there are zero floor fasteners attached to ladder frame rails down the entire floor length.. .

. ..Meaning there isn't a single perforation in the main frame beams that run from A-frame until those at for bumper mounts, all floor fasteners clamp into spars or outriggers, a very good structural practice as that induces zero flaws for bending or cracks to radiate to/from. The reduced width floor above the axles has proportionally the same number of fasteners as the full width sections yet is structurally weaker just by not spanning to shell.. The what & how that matters maybe is best left open to to any ones interpretation, just musing cause & effect...

Silicone was 0.063" dense Boeing surplus The photos tell the story, every inch of ladder frame, spars and outriggers padded with silicone, the POR-15 metal abraded with 400 grit and 3M 5200 slow-cure (18-hour) marine adhesive sealant welding everything together. Once the floor screws were in the 5200 had pressed out in nice beads at metal edges, no/low water intrusion/holding there either. We can dance on the floor without a single creak squeak or pop. I confess here in Minnesota it gets cold, ya see, and I wanted something to reduce cold-soak up through the frame.

[Jeremy9107]

Wabbiteer. Interesting. We had a gang of elevator bolts holding the floor down. So many that we had to order more after underestimating the first go around. Not just at the outriggers. There were at least 7 across each of the frame rails in addition to a single self tapping screw down the center of each.

Liking the thermal barrier/water intrusion barrier that you fashioned. Guess you are not worried about ever having to pull your floor off again? Wonder how that marine adhesive would do against Coosa board. It is not cheap. How much did you go through?

Thanks for the Bonderite suggestion. Ordered a bottle today. How long do you leave it on once applied? Do I need to scrub in any manner before rinsing judiciously?

[Jeremy9107]

Decided the plastic on the old wheel well tubs are too damaged, weathered and corroded to reuse. Made an offer to classifieds add for a pair selling for $75 (retail for twice that at VTS) but have yet to hear back. Thinking might refab with sheet metal instead. Plan to apply Herculiner to the underside facing the road and POR15 along the outer faces. Might even build 2 sets so can sandwich insulation between them. Has anyone done something similar and how did it work out? Would be interested to know how to improve on design as it seems the way the originals were set invited a lot of road water inside.


Pertaining to this...what is the purpose of the oval section of Alum that is tacked to the inside of the outer skin at each wheel well? There is maybe one rivet holding this in place at the rib.

[Wabbiteer]

AS Factory liked to reuse as much scrap as possible, the access hatch cut-outs scrap pieces got repurposed. On post 65 I noted: Wheel wells: ". .. my tubs had a doubling aluminum shim of .040 between plastic and the shell to better keep the unsupported open well skirt taut.. .". Here, have another cup of coffee?

According to the outline left on the shell in your photo it appears to have been wedged between shell and tub intended as a stiffener plate. On my '73 a 4"+ wide sheet runs almost the flush with the wheel opening for nearly the length of the skirts cut-out, sandwiched and riveted under the skirts' trim but also trapped in place by the openings trim rivets...

For fabricating metal some folks have wandered into air conditioning duct work shops and found a few of them up to it, even affordably. I* still like the idea of using the load-ramps as tub frame so adults could sit on them w/o damage or things getting stacked on them etc., foam board grouted & glued inbetween faces with foam-in-a-can for insulation...

[Jeremy9107]

Wabbiteer. Right, recall you saying that about those shims (a bit delayed).

Do like your idea about those ladder rails for the wells, especially if they need to hold weight.

Think we are going down the path of 16 gauge galvanized sheet metal. Will keep it off the top of the frame like you did and rather rivet it to face of frame and outriggers that make the wheel well space. Thinking of using silicone sheet or window flashing tape between surfaces to keep water out. Will paint underside with Herculiner and top sides with POR15 for good measure. Played around with many ways to recreate the original arched shape but then thought....why do we need that shape? Wheel wells will sit under kitchen counters on each side and was going to build a box over them for shelving. So why not just make the wheel well a box itself. Will be much easier to fabricate for an amateur.

[Jeremy9107]

There have been a slew of awful tasks with this renovation thus far. Nasty. Hazardous. Tedious. Nearly impossible. Dangerous. These are just a few words to describe. And when each task was done, was thinking it can't get any harder...then the next one comes along!
1) Taking out 100's of hard rivets to remove shell
2) Removing fiber glass insulation
3) Removing rust/paint from frame with grinder/cable wire wheel
4) Painting frame with POR15 using paint sprayer

and the newest addition, cleaning the interior of the outer skins...

[Jeremy9107]

The amount of Vulkem sprayed on the inside of the outer skin seemed excessive, and it attracted adhesives, dirt, fiber glass, etc. Was going to leave alone but didn't think this would be good surface to tape and glue when putting new insulation up.

Spent the past week (2-4 hours each day) scraping that stuff off the skins. Experimented with many products but arrived at Xylene as the best choice. It worked best when the temperatures were cool as it evaporated quickly when hot. So worked at night time. Sprayed on. Used plastic scraper, scrub brush and 3M scouring pads to get most off. Then followed with final spray and rag. Took almost 5 quarts of Xylene but it finally cleaned up.

There was corrosion along the skins that wrapped underneath, and some other areas at the end caps and door. Following advice, used Alumiprep 33 to halt and clean up. On lighter areas used 1:4 dilution, sprayed on, set for 3 minutes, then rinsed off with garden hose. Worked bottom to top. On the heavier corroded areas, used 1:2 dilution, sprayed on, set for 5 minutes, then scrubbed with 3M scouring pad, then rinsed thoroughly. Before and after below.

[Jeremy9107]

Spent Saturday bolting the floor down. This took a lot longer than planned for. Decided to use zinc coated steel elevator bolts with neoprene zinc backed washers and nylon nuts. There were over 100. Kinda tricky getting enough pressure on that flat head to drive nut on without just spinning. Came up with a "block lever" that gave enough pressure to stop the spin.

[Jeremy9107]

Sunday was a long awaited milestone...shell back on. Had to rebuild gantry as wind storm had pulverized previous one. Nothing pretty. Mostly scrap lumber and 2x4s created from beams cut with chainsaw.

Took 110# A/C off first. Cut rivets from inside and used heat gun to soften Vulkem on top. Then lifted with assistance from pole on floor jack inside trailer. Not sure what we will do with cooling yet, but this unit did not have a cover and was not working. Really have not had much need for A/C where we have camped the past 5 years. Might go swamp cooler route eventually?

Carefully backed trailer under and lowered shell back on. What a relief! It did take some maneuvering getting the front and rear holding plates tucked inside skins. There was some early corrosion on them, so used Alumiprep 33, painted with POR15, then covered with window flashing tape where steel was to be in contact with aluminum.

[dbj216]

Very, very good work by the amateur. Your nasty jobs have resulted in a solid frame, solid subfloor, and a very clean shell that has now returned home.

I wonder how many hours of your hard work it took to arrive at this point in your rebuild? A few hundred I would guess.

Now you have to reattached the body to the subfloor and frame. That structure is called "semi monocoque" similar to early aircraft. Each one of those three members depend on the other for strength.

Go Jeremy Go!

David

[Jeremy9107]

David. Thanks. Think you are spot on with that guesstimate of hours thus far.

[Jeremy9107]

Thinking forward and need some help with how to repair the outer skin damages that became more apparent when the inside of the skin was cleaned. Not looking for perfect as like to have some wear and tear for character. But would like to smooth out some.



Had no idea this hole was there until removed Suburban heater. Think there was a pressure point that eventually just rubbed through. What is best thing to do here?

[Jeremy9107]

Have read a lot about the water build up on the bumper box that seeps in through the rear floor. Definitely want to fix that as had a lot of corrosion there on skin, C channel and holding plate.



Found this post from many years ago :

http://www.airforums.com/forums/f305...tml#post664972

Seems like a great fix. Didn't want to hijack vhord's idea without permission but was unable to PM him. How did he get that 90 degree angled piece of aluminum to bend to match the curve on the shell?