rust between door skin and shell

[sam dupont]

A friend is restoring his car and I haven't had the experience to answer his question. On the back side of his door where the shell and the skin are crimped and welded, surface rust exists. He wants to tear it apart, clean the rust and put it back together on the advice of a friend who has cars in SEMA every year. I ask: where does it end? Wouldn't there be a thin layer of rust between every panel?

Will phosphoric acid wick in between where the skin and shell come together?

 

[steve340]

It will wick in there to a certain extent. The call is depends on how bad the rust in the fold really is.
My experience - if you can see it externally/slightly flaky it is probably worse when hidden in the seam.
The factory certainly would have just folded it together no matter what was there and then it was out in all weather for 50 or 60 years.
If it is not exposed and repaired it could bubble out after painting.
Depends how fussy your friend is and how much he is prepared to spend.

 

[eldubb440]

eastwood internal frame rail coating is very watery, I have used it in the bottoms of doors

View attachment 1523657

 

[icetech]

I have used phosphoric in a bug sprayer to get into hard to reach places... My car has/had rust in every seam and it scares the hell outa me (michigan ptsd) so.. i tried to kill it in everyway i could

 

[eldubb440]

if using phosphoric acid in the middle of restoration work, it must be properly neutralized to prevent an adhesion nightmare

 

[sam dupont]

eastwood internal frame rail coating is very watery, I have used it in the bottoms of doors

View attachment 1523657

my friend is taking advice from a guy who gets paid to do it perfectly. Going to that extreme seems too much to me. I don't have any panels I could paint with a phosphoric treatment and then split apart to see if it soaked everywhere between the panels or just sealed the perimeter.

I've had success with Extend, and it is rubbery. It does accept primer very well when covering it.

 

[icetech]

my friend is taking advice from a guy who gets paid to do it perfectly. Going to that extreme seems too much to me. I don't have any panels I could paint with a phosphoric treatment and then split apart to see if it soaked everywhere between the panels or just sealed the perimeter.

I've had success with Extend, and it is rubbery. It does accept primer very well when covering it.

i used the phosphoric in kleens metal/cement prep from Home depot (cheap and phosphoric) the stuff is about as thin as water..

 

[WileERobby]

A friend is restoring his car and I haven't had the experience to answer his question. On the back side of his door where the shell and the skin are crimped and welded, surface rust exists. He wants to tear it apart, clean the rust and put it back together on the advice of a friend who has cars in SEMA every year. I ask: where does it end? Wouldn't there be a thin layer of rust between every panel?

Will phosphoric acid wick in between where the skin and shell come together?

What do you mean by "tear it apart' ? Remove the outer door skin from the shell ? Or, gut the door to address the rust in the seam ?

 

[eldubb440]

in more ambitious times, I have removed the bottom inch or so of door skin and either de-rusted it or replaced it

every job is unique and there is always a line to draw somewhere

 

[icetech]

i have to fix the lower corners on my drivers door, just gonna cut them out and replace the metal ALA Fitzee.... will never be perfect but it's a driver...

 

[Bighouse]

Most repairs will last OUR lifetime. I’ve seen people separate at the seams and weld it all back together. Me? Nope.

 

[sam dupont]

I bought thousands of albums from a serious collector so I'm buying an ultrasonic record cleaner. It can be used to clean other things, so I'll find a car part with two panels that fit tight like a door skin and see if the ultrasonic cleaning action can remove corrosion between those panels that are tight fitting, but separate

 

[sam dupont]

Most repairs will last OUR lifetime. I’ve seen people separate at the seams and weld it all back together. Me? Nope.

My opinion to him was: the car has not seen rain in 30 years and will only see it by accident in the next 30. Treat it, paint it, get it back together, and start having fun with it.

 

[eldubb440]

you could pry the seam apart lust a little; and hang a bag of molasses/water on the door for a couple of weeks

 

[sam dupont]

Molasses took that off? hang a bag on it? Wonder how far it would reach without pulling the inner panel?