Paint Bubbles - Best Path Forward?

[betzgb]

I have some paint bubbling up from rust around the side markers and seam in the lower quarter panel. To see if I could get to good metal I ground down one side behind the side marker but still didn't get to clean metal and the panel is getting pretty thin. If I want to fix the rust right and not see it again for another 40 years, is metal replacement the only option? POR-15? Where I can grind to clean metal then acid etch would that fix it permanently?

Thanks for the advice, working on the do's and don't of body work...

 

[rojo23]

instead of grinding you may want to media blast the rust pits. after the rust is gone, etch primer and then body filler. if the metal is flimsy then you may want to cut it out and replace it with good metal.

 

[bronkenn]

If you want to prolong the inevitable panel replacement, then you can blast the spots that are bubbling and paint some POR on it with a small brush and top coat with some color. Will buy you some time.

 

[betzgb]

I would like to fix it this round and not mess with it again for decades. Sounds like blasting and POR will not be a long term answer? Looking for those who have gone this path and who far down the road did it get you?

 

[reamer]

The whole seam is already compromised, your seeing maybe 20% of it, Fix that and ya didn't get the stuff to the left and right of it. The seam gets moisture from the inside IN the wheel well.... you want 40 years (instead of 4 years)? whole seal/panel replacement with proper sealing from both sides (which Ford didn't do), is the only option......

 

[nvrstuk]

reamer is right.... entire seam has to be exposed (inside the tub also) and since I did this recently. I did not have to replace the lower or upper panel but my panel didn't have holes, just extensive pitting. I had POR'd this seam back in '96 when I painted it. Lasted about 25 yrs but not 40 yrs.

Sealing it up on the inside is important. I haven't had a full top on my since '98 and I come back from snow wheeling with a couple inches of fresh in it so that contributes...

 

[betzgb]

Well 25 years with POR is more than I would have expected! When you say expose the seam inside the tub, you mean remove the entire lower quarter to get between the seam between upper and lower panels? I can see the spot welds for the lower panel in the B pillar but not the entire run of the C pillar nor on the top side of the upper when looking from inside the tub. Was it spot welded from the topside also? I'd love to save the original panel but I suspect I will trash it while trying to separate all those spot welds. Can this be done or mission impossible?

 

[nvrstuk]

I am not qualified enough to tell ya.

I know if you have the time, energy and money to do it now and if you REALLY want it to last 40 years you need to replace the panel. I'd be willing to bet more than 50 cents that you will need to do the other side also if you want it to last 40 years. It will start blistering thru... just a matter of time and it will be less than 40 yrs. Sorry.

 

[reamer]

Very tough to do, Do you know how Ford made these? the top-exterior panel (the cap bolts to) is actually the lower-interior wall. and the lower exterior panel is just a "Skin" where they are spot weld together, it is in the interior-wheel well high up where you can't get in.
Even with new panels (which I did) almost impossible to spot weld.
I mated the 2-panels together, drilled 2 holes, 1 by B and one by C pillars, used panel adhesive on the entire mating surface and bolted them together.