The galvanic reaction between brass and aluminum is worse than the reaction between steel and aluminum.

May I suggest you purchase Stainless piano hinge and use that in place of the steel hinges. Piano hinge designed to be welded into place does not have holes in it and can be drilled as desired.

As it sounds like the door skins are just skins replacing the skin with 5000 series aluminum or 6061 might be a road to a better product with one heck of a lot less work.

After fiddling with the stainless hinges sending them out to be electro-polished is something that I like to do, this removes any steel left from my drill bits and the like. Besides stainless rusts too, just ask any boater.


Timothy

Patching the blisters as gregH did, lasted about 3 months on mine. I dismantled the door & found the plywood core water-soaked. I rebuilt the door the hard way, with plywood, urethane insulation, & a skin of aluminum flashing material (couldn't get thicker material here in the boondocks).

New York Bill's solution is easier & much more elegant.

IMHO the corrosion resulted from iron leaching out of the luan plywood core, & reacting with the aluminum. Why? The wet plywood was next to the corroded exterior skin. The inside skin next to the insulation was unaffected.

I sealed the edges & the rivets as carefully as I could to exclude any more water intrusion. Time will tell if it works.

Hi, Folks....
I've just joined the Barthmobile.com forum. This paint blistering reminds me of a similar condition we used to encounter with airplanes. It was known as 'Filiform Corrosion' (hope I've got the spelling right) and it usually appeared where dissimilar metals joined. It also seemed to show up more on airplanes that were based near the salt water & air.

I don't have 'My Barth' just yet but I will be looking for this condition on each unit we consider for purchase. Anyone who encounters the problem might want to consult an aiplane paint shop of good character to see how they deal with the problem.

Lou

Wasn't this subject covered a while back? Seems the bay doors were the same material a trailer doors and you could just make you own.

But memory is the second thing to go!

quote:

Originally posted by Gary Carter:
Wasn't this subject covered a while back?

Yeah, Bill NY had a real good post on it.

I've been following the thread here and 0n "modifications" concerning our errant doors and there's a lot to think about. I keep comeing back to the steel hinges and non steel hinges ,or maybe stainless, and am still wondering if that is not the cause of the problems...has anyone checked to see if their bad doors are hinged with steel and the good are something else? Timothy referred to the incompatability of brass and aluminum so I assume that the doors that are OK are stainless.
On another slant on this..... from what I've read, all the bad doors are only bad on the outside, is this correct? My bad ones are OK inside causing me to wonder if I could get away with turning them around.
One of the main problems I've encountered is that my worst door has three colors of the graphics coming together. I received one estimate to paint the door At $570.00. So off to the men's mall to get spray cans as close as I could to the original..not even close!! I'm sorry to report.
Well the adventure continues and I'd like to thank those who chimed in with their ideas...I'll let you know where this ends up.

Greg Hamilton
Burnsville, MN

95 Regal 28'

Greg, check my latest post on the other thread, & El Segundo Bill's post right after that one, where he blew water out after drilling the bottom of his doors. My corrosion was clearly water intrusion, not dissimilar frame metals, but I think iron makes the luan red, & when wet it leaches out of the luan plywood to react with the aluminum.

Aluminum riveted to steel causes your pop rivets to corrode where the front cap attaches, & I've found similar problems in other places where aluminum is riveted to steel frame members, but it wasn't the cause of my door corrosion.

Gentelmen: I have followed your posts on this door problem and looked mine over. They have the same problem of small blisters that, when sanded, form holes and show water soaked Luan beneath. There are lots of ways to address this but as you have seen most the band-aid approaches are very temporary. To solve this I went to a friend who operates an FAA structural repair center and showed them the problem. Here is what we did: Remove the hinge and all pop rivets; discard the steel hinge; then remove the skin, discard the inner Luan substrate and clean all surfaces. Replace with aircraft honeycomb aluminum in the proper thickness and bond to two new sheets of aluminum. Paint the interior portions with Zip Chemicals D-5029NS Corrosion Inhibiting Compound (available from aircraft supply depots at your local FAA repair stations or stores - some are on the internet or you can contact ZIP Chemicals in San Jose California). Then replace the door frame and weld in place (this means of course the skin is thicker than the original, I used 5/32 aircraft aluminum) and then install an aluminum aircraft hinge using flush rivets and not pop rivets. The FAA certified stations have the large equipment necessary to install these rivets and at the same time coat the mating surfaces with more of the corrosion preventative. Once installed, use a two part auto or aircraft paint and you are done. Expensive? Yes, in the neighborhood of $250 per door, less painting, but for our Barth's it is worth the effort. The sealing and corrosion preventing treatments make these permanent fixes and they told me the reason it should be done is the same heating, cooling and condensation occurs in aircraft with each flight, so this removes that possibility. The finished doors are lighter than the soaked wood ones I removed and they are much stronger. Mine has eight doors and it cost me about $2400 with repainting. Having them all done at once got me a discount of several hundred and I did the removal and installation. They did the work and sold me the hinge material. The hinge was secured to the door with flush rivets and with pop rivets to the coach exterior. Stainless screws could also have been used on the coach rail because there is not much chance of water getting in as the weatherstripping does a good job of sealing this. The same problem existed in my pre Barth SOB but in that case we stripped off the exterior plastic, removed the wood, put the two skins in a jig and filled with two part urethane foam. Once hardened we trimmed it to size, reinstalled the frame and put it back on. That was much cheaper, but so was the quality of the coach.
Tom

Apparently, somewhere along the line, Barth noticed this problem, as my doors have weep holes along the bottom which would keep water from accumulating.