Dealing with inaccessible areas

[gzig5]

Trying to decide how to go about dealing with "surface rust" in some of the inaccessible areas like the inner roof structure, inside rockers, and in the A and C pillar areas.  This car will not be dipped so I need to work most of it mechanically or locally with chemicals.  I've got my roof and quarters off so I plan to wire wheel/abrade everything I can reach and apply primer (which will be another question to address).  The areas that form tubes and pockets are what concern me. I am considering to use the Eastwood internal frame coating which is applied with a small tube snaked up inside the frame tube.  But I'm not sure how good of a rust converter that is.  So I'm thinking about trying to use a similar method to mist Ospho rust converter in those spaces first and after giving it a couple days to dry, then applying the Eastwood stuff.  Just trying to do my best to slow the rust on these surfaces that aren't seen.  As you can see, I had considerable rust on some of these areas that the factory never coated. 

Is this a reasonable approach?
How have you handled this on a car that isn't getting dipped? 
I really don't want to drill out welds and partially disassemble the structures either, as good as that would make me feel.

[Blowout]

 

[EDL94]

I used the Eastwood internal frame coating in all of those areas. It seemed to spray no well. How good it will be long term???

[BIGSHCLUNK]

I have no answers but have seen this "internal condition" on cars we've cut apart. Even tho they looked good on the outside. There is no doubt we live in the rust zone.

[Dmod1974]

Eastwood's internal frame coating is about as good as it gets without cutting and blasting the insides, which is completely unrealistic.  I used that on my winter beater truck and it has held up quite well for the last 6 or 7 years.

After almost 50 years the roof structure on my rot box just had minor surface rust with the exception of the sail panel areas that had some rot on the portion going down to the wheelhouse.  That metal will likely outlast us at that rate.

[gzig5]

It would have been nice if they would have had a deeper primer dip tank to run the bodies through when they built them back in the day, then these issues could have mostly been avoided.   Obviously that wasn't their priority at the time.  I'm not going to sweat it too bad then. I'll address what I can reach with the abrasives and use the Eastwood on the internals.  Once it is in primer of some sort I'm sure it won't bother me near as much as seeing all the crusty stuff out in the open does.  I've got some Eastwood epoxy primer and hopefully the areas I start on will not flash rust before I get all the way around  it.  I may restructure the order I do a few things to reduce that likelihood.

[soundcontrol]

I used Eastwoods Internal Frame Coating in my rockers and inside the frame. Seems to cover well. Before spraying I cleaned the areas with a steel brush made for small chimney pipes, and I attached a hose to the steel brush (which had a long handle) connected to a shop vacuum to get the dust out while I was cleaning. I also used a USB camera and checked all those areas before and after spraying. This is inside my rockers (convertible).  I think it will last my lifetime at least.

[Lunchbox]

Looks good, do you have a before picture?

[gzig5]

I used Eastwoods Internal Frame Coating in my rockers and inside the frame. Seems to cover well. Before spraying I cleaned the areas with a steel brush made for small chimney pipes, and I attached a hose to the steel brush (which had a long handle) connected to a shop vacuum to get the dust out while I was cleaning. I also used a USB camera and checked all those areas before and after spraying. This is inside my rockers (convertible).  I think it will last my lifetime at least.

A man after my own heart!  I happened to get the long stem bore brushes out this afternoon that I got from the tool guy at the World of Wheels show, and hit a couple areas.  Need to get the snake camera out to check results in the A-pillar.  It looks like that should suffice.

[70Challenger440]

I hope I don't sound like a butcher, but bear in mind  I did this back in the 1980s when I was young.  I literally just poured "Por15" into rusty non-accessible areas. Forty years later I still own this car and its still  fine and no one would know. It will stand the test of time as long you keep the car relatively dry and garaged thereafter.

[soundcontrol]

Looks good, do you have a before picture?

Yes, this is during steelbrushing, I cleaned a bit more after picture was taken.

[soundcontrol]

I hope I don't sound like a butcher, but bear in mind  I did this back in the 1980s when I was young.  I literally just poured "Por15" into rusty non-accessible areas. Forty years later I still own this car and its still  fine and no one would know. It will stand the test of time as long you keep the car relatively dry and garaged thereafter.

I think we actually just could leave it as is, maybe some WD40, but we can't, we have OCD...