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Discussion Starter · #1 ·
I am getting ready to paint my '68 VW Bug Convertible and I have a few unanswered questions. This is my first paint job and I really want to have a good result, so I've been doing a lot of reading.

As for my equipment, I inherited a small compressor (20gal 5hp) and a Campbell Hausfeld siphon style gun which seemed to work okay for the primer. To be honest, I need some help with gun set-up too. When I shot the primer I set my PSI at the gun at 40psi and set the adjustments until I had a cigar shaped pattern and the dropletts were as fine as I could get them. I'm spraying in my garage which has been retro-fitted with a make-shift paint booth per instructions on this site (Thank you). This set-up worked good thus far, but I am worried that the paint will be much more difficult to apply and I may need to get some new equipment.

I started with all of the major body work and sanding, I did a really good job of cleaning it with a dish soap and then wiped it thoroughly with a tack cloth and just shot a coat of "Cross-Fire" self-etching primer on it. (Napa Brand) Now, I still have a few areas of the body that need some more working and was wondering, should I try to straighten these areas first or shoot my primer/filler next?

I plan to use an Acrylic Enamel paint and I think I will need to use a two-stage system. My question here is, can I use PPG or DuPont products over my Napa self-etching primer? If not I will stay with the same brand, but I am worried about yellowing clearcoats since the main color will be white (I've heard that many low-budget clears will yellow). The main reason I would like to use a two-stage is because I would like to add some pearlescent ghost-flames as well and I have read that these look best when a two-stage is used, also I hear two-stage is a little more forgiving to apply.

Any help with this will be greatly appreciated!!!
 

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'Stock' is just wrong!
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Paint's not hard...

1) Your 5HP compressor is fine (unless it has an oil-tank on it... if it's got an oil resevoir, it's made for air-tools, and you'll contaminate your paint). I shot a whole Olds Cutlass once with a 1HP compressor. Just make sure you give breathers as you shoot, to ensure you maintain as consistant a hose-pressure (if you've got a pressure regulator on the gun or at the other end of the hose, you'd be fine without waiting). If you notice your hose pressure dropping below 40, you should stop. As far as your suction gun, I'd ask "why?"! The suctions work fine, work better with thinner paints than primers, but you'll end-up using 4X the amount of product than if you shot with an HVLP. ATD sells a cheapo entry-level gravity HVLP. They're easier to use, and for around $70, you'll save money buying one as opposed to using 3-gallons of paint and clear.

2) Self-etching primer is intended to apply directly to metal. The acid etches the metal, thereby increasing the metal's surface-area, thereby increasing the adhesion. Try not to use it on subsequent coats, but it's fine for direct-to-metal.

3) Straighten-out the metal before shooting any primer, and certainly before putting any plastic filler on it. You can't beat-out anything you put filler on, and it's way-easier to beat a panel with a hammer for a few minutes than sanding filler for hours. If you're thinking about using the 5HP compressor to run a jitterbug or a DA-sander, it'll never keep up. Beat-it, file-it, beat the low-spots some more. Prime with your etching primer, then fill&sand.

4) DO NOT APPLY YOUR PAINT DIRECTLY TO THAT ETCHING PRIMER! Instead, pick up some sealant, or an epoxy primer-sealer, then paint. The porous primer will soak-up all your expensive paint (and may be incompatible with some solvents in the paint).

5) Two-stage paint is easier and harder to use than single-stage. While it's true, that you'll probably need 2-stage to do any ghosting or pearls, I find it harder to keep from running. It's way-easier to sand-out/buff-up a single-stage run.

Good luck!

-Kustomizer

P.S. You'll have way-less overspray and fumes in your garage with HVLP, something to think about if your garage is attached to your house.
 

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Discussion Starter · #3 · (Edited)
Thanks a bunch Kustomizer!!! I really appreciate it!!!

I still want to touch on a couple of things though if you don't mind a few more questions....

1) My compressor has a small hole for oil on the pump, but I don't think it puts oil into the air tank...??? My uncle has a HVLP gun, so I think I will use that.... :D

2) Thanks for the info here! I planned on using a primer/sealer first....Is there a type you recommend?

3) If I have already put some plastic on an area and I have found a few high spots (not major) should I try to fill them up or strip it down and start over?
Did I read that right...Use the self-etching THEN fill and sand? Will the plastic stick to the etching primer?
.....Yeah....:sweat: Found out the hard way with my DA sander...

4) I guess my real question here is can I apply ANY primer/sealer on top of the Napa brand self-etching primer?

5) Cool! hat helps me out a lot! I was going back-and-forth with that decision.... Is it true that some clears yellow? If so, can you suggest a good clear? The car will be white, so I would hate to have a yellowed clear on it!

Thanks again for all of your help on this!!!!:thumbup:
 

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'Stock' is just wrong!
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List-o-crap

1) You should be fine. Sounds like an oil-less compressor.

2) I think it boils-down to what you intend to shoot for paint. I use only Dupont paints (for the most-part), so I would lay-down Chroma Premier sealer or Prime&Seal (I used to use VelvaSeal, but that was more for laquers). Dupont also makes "Epoxy DTM Primer-Sealer", where DTM stands for "direct to metal." Use-up your NAPA stuff (I doubt NAPA actually made it, but I guess it's possible... it's probably something like Benjamin Moore, which is okeey-dokey in my book). Whatever you find from your jobber should be fine, as-long as it's a "sealer" or an "epoxy" under the paint. Do not paint over the self-etching primer (but it's perfectly fine to apply your sealers over the self-etching).

3) I never apply plastic directly to metals. I guess if you're using that metal-filled bondo-stuff, logic says it's okay for metal-to-metal. I just don't do it. You'll scuff-up the self-etching primer after you try to take-down your filler high-spots, in-which case you'll need to re-apply the self-etching over the filler/scuffed-metal. Don't "fill high spots" as you said, always work the area back down to metal with a wide sanding block (like a 2x4 wrapped in a full-sheet of 220-grit). You'll quickly figure out where the metal is and where the filler starts, and you'll apply THIN coats of filler to your low-spots. Lather, rinse, repeat, as they say.

3b) If you already applied filler, as soon as you whack the panel with a hammer, you'll bust it loose. That's why you should avoid filler at all costs (unless you're selling the car!). If you ever get a car-door ding, it'll remove a huge swath of paint! Filler aint "lead" like the good ol' days, it expands and contracts differently than metal, and the first impact will show you.

4) Yes. The purpose of primers is to adhere better than a paint would, most have a lot of resins and polymers that grip like glue, but look like crap. Then, they give a rough texture (increased surface area) for the paints to stick to.

5) Not so much anymore. 20-years ago, maybe. Truth is, I used a rattle-can, cheap-***, Ames-brand "special", clear probably 6-years ago on a buddy's snowmobile (the kind of buddy that never pays). Still looks good to this day. I think the yellowing was more a result of Ultra-Violet (UV) breakdown, and all of the major-brand clears today have UV-inhibitors in them (I could be wrong on this one).

For you low-buck painters, the foot-long 2x4 block wrapped in a sheet of 220 (or rougher), for sanding down panels full of filler really works. It allows you 2-hands to work the problem, and it's wide/long so you don't add your own dips into what's already a mess. Don't sand in the direction of the 2x4, you'll want to sand at a 30-45° type of sliding motion. Good luck!

-Kustomizer
 

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Discussion Starter · #5 ·
Well, once again you have given me some great suggestions! Thank you!

It looks like I have a lot of work still before I start painting, but if it will get me a good result, I'm in!

My main problem is the rear apron of this car. When I got it the apron was basically demolished. spent a lot of time beating it out from the inside and trying to get it as flat as possible. Then I put the filler on it. Once I put the etching-primer on I could see three distinct creases that I missed. I really hoped that I could fix it without stripping down, but....:( Oh well.....

Thanks!
 

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Filler

I'm not telling you you can't use filler... I'm just trying to tell you anything worth doing is worth doing well. The thinner the better.

Don't forget, when you pound-out the metal's dings, you're actually stretching the metal. Striking the metal with a hammer into an anvil (aka "on-dolly") will shrink it slightly where you struck it, but it makes the metal hard where it shrunk, possibly making further movement difficult.

If this is your first car, you're not going to do a perfect job anyway, no matter how good you are! Filler may be a good way to "get it done", which is better than my latest project, a '55 chevy that's been torn apart in my garage for over a year.

I attached a picture for your amusement.

Cya!

-Kustomizer
 

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Discussion Starter · #8 ·
Kustomizer, you have been super-helpful, and I want to say thanks, yes again....

I thought I'd post a couple of pics of my works-in-progress....
 

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Discussion Starter · #9 ·
I hope nobody minds if I send a few replies with pics attached.

Here is the rear apron I don't know how well you will be able to see the creases, but here it is...
 

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Discussion Starter · #12 ·
Here's my 69 it's not even getting as good of treatment as your 55! I promised her I would make it up to her though.....
 

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