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Now I am confused, Re: Filler.

KLUTZ

Luke Skywalker
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Before I put the "Bondoglass" over the areas I welded onto, dogleg, fender.. I asked a question in regards to if you put the filler right over on top of the bare metal or do you prime it first.
The count was 7 to 0 in favoUr of putting it right over clean metal.
Yesterday I was at my mechanic's shop picking up a rear rubber bumper and was talking to him about it. He told me that the paint companies are now saying that you should put a coat of Epoxy or Etch primer on first, then the filler. He says they state that it will give you double the years of service of the repair since the filler has moisture in it as well.
So... do I need to remove my filler and start from scratch.. and etch first or leave it the way it is? Is it just a way for the paint companies to sell more product as well?
Experts please /ubbthreads/images/graemlins/smile.gif

Paul
 
As for filler, I say rough sanded bare metal. What is important is sealing water out from behind.

The filler will wick moisture if it has glass strands in it. So, it's important to seal (prime and paint) the filler as soon as possible.

On the back of your panels, use a good flexible seam sealer, then coat with a good rubberized undercoating, waxyol, or the ever-popular, POR15(without the seam seal, I guess).

That's my .02.
 
Mine was painted with epoxy primer then a skim coat.
 
On my 37 Chevy truck, my PPG dealer told me to seal the bare metal w/epoxy primer first, then add any filler, sanding primer, etc. They say this keeps the moisture from getting to the metal. I can say that this procedure works. I have spots I epoxy primed first 4 years ago, no hint of rust or moisture. Seems to be holding up just fine.
 
[ QUOTE ]
As for filler, I say rough sanded bare metal. What is important is sealing water out from behind.

The filler will wick moisture if it has glass strands in it. So, it's important to seal (prime and paint) the filler as soon as possible.

On the back of your panels, use a good flexible seam sealer, then coat with a good rubberized undercoating, waxyol, or the ever-popular, POR15(without the seam seal, I guess).

That's my .02.

[/ QUOTE ]


I did all of the above and used the POR 15 on all the inside areas.
So, again though.. differant ideas here too.

Thanks

Paul
 
Grind down weld, epoxy prime then fill. It is better for under the putty as well athe feather edging. This is the new school of thought (last 10yrs. or so). Prior it was just straight filler on the bare.

Patrick
 
Etch prime it & put the filler over the primer..that's how my body guy does it.
 
Wait, that's my body guy.
 
Were it me, I'd buy everything at the same place...decide what brand paint you're using & stay with that brand exclusively - & go through a paint jobber, not NAPA.
 
Krylon, rattle can.
 
[ QUOTE ]
Krylon, rattle can.

[/ QUOTE ]

/ubbthreads/images/graemlins/lol.gif Yeah, I know how much rattle can is on Miss Agatha!
 
Thanks so much for that link. Seems to be split 50 / 50 on this issue. I called the Maaco that did my TR7 6 years ago and asked them. Mike told me filler directly on metal as well, and the 7 stood up perfectly all that time.
Don't think I will hack off the work I have done now.
Paul
 
I suspect that over time filler on bare paint leads to rust at the interface line which will raise the filler. The two part goes on right away and stops any surface rust even and seals all tightly first. In my opinion.
 
Yeah, I started to learn new tricks when I started this B rebuild. Local paint supply guy LOVES to see me walk in.

Epoxy primer will adhere to a GALVANIZED surface (if prepped right)!! It's MAGIC stuff. I went with AllMetal as the filler, over the primer. This B is nearly hermetically sealed in epoxy primer. /ubbthreads/images/graemlins/wink.gif
 
There was a time when I did filler right to raw metal...over the years, I've come to agree with prime first & then fill...I usually let my cars sit 4 or 5 years after paint before I put back together.....no problems with either but there are problems with the Karmann Ghia that we put filler directly to metal when we replaced the headlight boxes...we only primed it (haven't painted yet) & I can see rust popping up all along the welded edges..now, that might be because we didn't go over the primer with paint right away, or....
 
Well this might be an area I can help with. I work for the largest independent P&B supply in the southeast, Auto Color Co., and I also do paint and body work on the side and I have been to college to learn paint and body. Fillers are porous and urethane primers are porous so you MUST seal the bare metal before any filler is applied. There are many ways to do this, one is self-etch primers, basically a zinc chromate. These come in quarts gallons and aerosals. Companies like Sem and Dupont both make them. Another option is chemical treatment/metal prep. These are made by most name brand paint companies. I don't like these because they harsh chemicals that can be somewhat difficult to work with. The easiest and most accepted way of treating bare metal today is the epoxy primer. These work the best and are easy to work with. Once you have put 1-2 coats of epoxy on the bare metal you can start the filler process. Once you are happy with your putty work then you move to a urethane or polyester primer depending on how much blocking you have to do. Urethane primers are expensive and if you need to do some heavy blocking you can spend a lot of money. The primers I like to use run $250.00 and up per gallon. I also use a polyester primer made by Fibre Glass Evercoat called FeatherFill G2. This is an extremely high build primer that dries very quickly in the right tempratures (70-80 degress) and sands very easy and it will not shrink or crack and if VERY hard. You can apply paint directly on the FeatherFill but id you have many color primers on the car it is very wise to seal the car before paint.

Just my long .02 worth

p.s. my favorite paint is Dupont Chomabase or House of Kolor.
 
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