How far to Rub back??

G'Day

I started stripping and making some body repairs to my Beetle this week in preperation for a new paint job and soon discovered that it has more than 10 coats of paint on it. I have been using a 125mm Orbital Sander to make a start on the larger panels , but have found that it is rubbing through to bare metal in some places. Will this matter in the overall scheme of things or will it create more work?

Cheers Paul

hey paul

Whats colour will it be???

alex

I dont know yet I keep changing my mind every 5 seconds!! but I'm thinking a little bit on the Hot Rod side

When I rub back I always stop at the top of the crack... 😂

Hi Paul,

At this stage I think you might as well take most of it back to bare metal with 180 DA disk pad.

You are better off starting from scratch as sometimes there might be a reaction when you put the color on at the final stages and you'll have to start all over again.

Is it getting painted in Acrylic or 2K?

There is no substitute for going all the way.....

this far...

With that many layers of paint it will be more important to remove any substrates that will have a chance of reating with the top coat.

Clean & strip discs as made by 3M are a good way to remove the paint to bare metal.

By the looks of your photo, you may have the car pretty much stripped of all its bits and if you're going that far with it, the next logical step would be to take off all the old paint which if nothing else will lighten the car up, being it will be 10 coats lighter, plus any body filler that might be in there..
Be prepaired to find some nasty suprises under all that paint, (my brother had his 1960 Pontiac taken back to bare metal, they put a disc sander on the 1/4 panels and it went straight through.. No metal there, just plastic filler)..

Remember you will be creating extra work for yourself by taking the car back that far, so if it's not going to be a "Restoration project", this may make it one anyway...
The only other advice I can offer is, having been around the panel and paint industry for a number of years, I have seen many paint jobs where the car had been taken back to bare metal and rust had appeared long before the gloss had fadded off the paint... (You need to be very careful when going back to metal)...
Good luck with your project...

If you do go back to bare metal don't forget to condition the metal before etching. Deoxidine is the one of the best. 1 litre will do the whole car. Get a spray bottle, fine steel wool and some really good rubber gloves. Rub it in, wait for the acid to do it's thing then rub/wash it off as per directions.

Thanks for the advice, I have never done any real body work so excuse the novice questions, I am sure I will have many more.

I am not sure if acrylic or 2k will be used at this stage, what I am trying to do is get it point where it is primed and rubbed bach before getting it painted proffesionally.

Finished rubbing back the passenger side rear quarter to pretty much bare metal as per the pic.

After reading heaps on the whole topic on this forum and the net, I am seeing that you need to etch prime the bare metal prior to high fill/primer. Do I still have to treat the bare metal with Deoxidine before etch priming? and if so will this damage any filler already on the panels?

I was hoping to leave the filler in the quarter panels (as per the pic because it seems to be a fairly good repair)

I am also presuming that I can use filler over the top of etch primer if needed , is this right?

How long can I leave it in etch primer before High Fill/Primer?

any advice appreciated

[ Edited on 7-1-2006 by 1303 ]

I'm no expert but here's what I have been learning and applying from people who know better than me.

1303 wrote:I am seeing that you need to etch prime the bare metal prior to high fill/primer.

Etch prime does exactly what the name implies... it etches the metal for proper adhesion. Straight primer will not get as good a hold on bare metal.

1303 wrote:Do I still have to treat the bare metal with Deoxidine before etch priming? and if so will this damage any filler already on the panels?

It is a good idea. Deoxidine (or similar) is a mix of phosphoric acid a few other things. It cleans, completely degreases, gives an etched surface and converts iron oxide to a much happier state.

Yes, phosphoric acid will attack the filler.

1303 wrote:I am also presuming that I can use filler over the top of etch primer if needed , is this right?

Correct.

1303 wrote:How long can I leave it in etch primer before High Fill/Primer?

Depends on the environment, but the shorter the time the better.