as some of you may be aware I am currently doing some rust repairs on my beetle.

My question is, should I etch prime the repaired areas prior to using filler, or should I just put the filler straight on the bare metal.

I have previuosly always put filler straight on bare metal, but there is a bit of talk around that says etch prime first then filler on top of the etch primer.


I am painting in acrylic lacquer, using a single stage etch primer.

if its etch primer on first, what do I then have to do to the etch prime prior to putting the filler on? do I need to sand it? what grade of abrasive? or do I key the metal with a course wheel prior to etch priming & that will do?

What do the gurus reckon?

Cheers
Brendan

my advice etch prime. Filler. Primer. Paint. Yes you should scratch the sirface first. A green scotch pad will be enough to get bite.

Good luck

Yep etch first, as this will provide the seal for the metalwork.
Cheers
D

Do not put filler over a single pack product of any kind. Filler is two part. Single part products have movement and adhesion to any two part products on top is limited.

A two part epoxy primer is the best way. Then a minimum of 240 grit sanding before filler. PPG, Ameron, Concept, Spies Hecker, De Beer all have products in their range to suit this application with varying levels of price and user features and product functionality. If this is not an option, then bare metal filled and primed without being left exposed for too long is the next choice.

Filler, and single pack primers are hydroscopic, meaning they accept moisture from the air.

I've always used filler on bare metal...
it grabs onto the bare metal and never comes off...

LEE

PS: I'm no expert...

Filler over bare metal will work. If it is done on clean steel and to manufacturers specifications, it can last between 5 and 15 years. Same sort of age most cars endup lasting. If you want more from your restoration, then epoxy priming the metal is a better way to do it.

Well I went into my local auto paint supply joint & he didnt have a clue what I was talking about when I asked for a 2 part epoxy primer.

The only 2 part primer he had was this: http://www.hichem.com.au/hicheminfo/PIDS/Two_pack/2prp.pdf 

if i had time on my hands he might be able to get me this (maybe). http://www.hichem.com.au/hicheminfo/PIDS/Two_pack/2pep.pdf 


So after spending an age on google trying to determine what I need & a brand that I might be able to source semi-local, I have come up with these couple

http://www.tat-co.com/products/preps-and-primers/2k-epoxy-primer-sealer-6134/ 

http://www.conceptpaints.com.au/TDS/2K%20Epoxy%20 (Urethane)%20Primer.pdf

I found the data on the web very confusing to a punter as to what is compatible for what I want to do, ie 2pack epoxy followed by acrylic topcoats.

Any further info you could give me would be great, like a brand & a product code or name? as I dnt reaaly understand the paint companies technical speak very well.

Thanks again

You there guys??????

We use EPOTEC 408 by Protec. It is an epoxy primer that is real strong on clean metal and seals it. Then after curing rub it with 120grit paper and fill over the top. Follow the manufacturers directions properly. It comes in 3 colours black,white and green/grey.

Thanks Peter

So this is technically an industrial paint yes? most of the ones I've looked at were industrial type paints & I wasnt sure if they be compatible with what I wanted to do.

I'll see what I can scrounge up, rang a paint supplier in the next nearest town & he wants to sell me a single pack primer.

I would guess that what your saying here about two pack product over a single pack product would also apply to 2 part glazing putties? if used over acrylic primer/surfacer?

so I should go 2 pack products until I'm finished with all body working.

Cheers
Brendan

Two part cured products all the way is the only way to ensure proper adhesion and prevent movement of underlying products.

Epotec 408 is industrial and real strong and permanent. We start all restorations on steel/ aluminium combined body vehicles with it. That is $100K plus restorations, so the start is the most important part.