a little panel/paint advice

[seany-boy]

I have a fair bit of 'hazy' cracking coming through my paint on my TBird and started removing the paint to assess the size of the problem.It comes through from areas where filler was used (I think back in the 80's it was done) and the filler has hairline cracks through it as well- but so far no signs of new rust creating this problem.
So am I best to take the panel back to bare metal, remove the filler and start again or would the self levelling ability of a paint like KBS or POR15 cover and seal these areas for a repaint?
Second question is the bottom surface of the doors seems to have a fair bit of pitting that has been painted over so they may have used a rust convertor or similar way back then (again no sign of much new activity), if I remove the paint and treat it then use KBS/POR15 am I right in assuming I should remove the door and flip it upside down in order for the product to smooth out correctly? i.e. would it self level upside down?

As you can see, I am lazy by nature and not experienced in painting!
Cheers.

[evan]

I'm no painter but I don't think it's wise to paint over the old filler (I doubt KBS/POR will adhere unless metal is clean & prepared anyway). You need to remove everything & seal the metal with a good 2 pack epoxy & then apply fresh filler. Filler is porous so it's important to re-seal the repair promptly with epoxy before final prime & paint.

For the bottom of the door, you need to bare metal it inside & out. You could seal both sides with KBS/POR to slow down the rust. If you plan on painting the visible section, you'll probably need to spray your primer over it before the last coat fully cures, otherwise it won't adhere. I was told this years ago by a KBS agent. They told me they once sprayed an entire car with KBS & successfully primed over the top. I can't say I've tried this though. Have a good chat with a supplier that actually uses the stuff before you start.

Evan.

[seany-boy]

cheers Evan

[barnett468]

yes, all the bad bondo must be completely removed.

[seany-boy]

cheers. Started the process, had a visit from a great painter friend who has set me up with the right sanding tools and the work starts now 

[seany-boy]

so I think I got lucky with the panel/paint guy. A young guy in Bayswater who has been doing a great job, his brother is the main painter so they keep it all in the family. They were happy to work with our choice of products and even process. Been up and inspected every step with my son who was a qualified spray painter previously, done a great job on the body and about to get the car back to start the re-assembly. Will give it the real once over when back but so far could not have been happier.
Went to someone who was previously recommended a couple of times on the forum only to be told 'I don't do big jobs like that any more' so I think it is getting harder to find the competent and willing!

[jiffy]

Sure looks good

[barnett468]

Look nice but it's too late now to properly repair the doors, which involves using acid to de-rust them, but you may be able to lightly sand blast the inside of them along the bottom then epoxy primer them then spray ruberized undercoating inside along the bottom to make them waterproof. some undercoatings will stick to bare metal as well.

[seany-boy]

cheers Barnett,

The door were taken off and attacked while off the car. They have come up well, re-assembly ongoing