priming the car

[cbudvet]

I am planning on having the shell of my 240z chemical dipped to remove the paint, rust, etc. My question is: when you are down to bare metal, what is the best way to prime the metal? I have seen cans of self etching primer at Autozone, etc. but have heard that many primers are actually porous and won't save the metal from rust. It may be some time between the stripping and the painting. I don't have the money to go straight from the dip to paint. Also, there is some body work to be done. So, can I buy a bunch of cans of primer and slap some on to protect it until the eventual paint or is an epoxy primer (that someone else has to do) the only way to go? Thanks. Carl

[BD240Z]

Carl,

It's nice to see such a low VIN car getting the royal treatment. I don't have an experienced answer for you, but I don't believe the rattle cans will protect/seal the metal from moisture.

Have you asked the supplier who's doing the chemical dip what they recommend? Won't the dip be followed by some sort of zinc phosphate wash? Some members here have had their car dipped, maybe they'll pipe in and explain what they did while waiting to have their car painted.

Good luck and post some pictures when you're finished.

Bruce

[hls30.com]

Depending on the condition of the car, I would wait to strip it until you are ready to do the work and get the project on the fast track, there is no point is stripping ot to coat it to have to strip it again.

If you are serious about chemical dipping, most of the baths offered will prevent flash rust until the chemicals are cleaned off.

The best long term answer to keeping a stripped body from rusting is paint-even a couple of thin coats of the cheepest white you can find.

Will

[JimmyZ]

Zinc phosphate is really a temporary coating for metal and should get primer ASAP.

I'm assuming the dipping place uses electolysis in a lye or soda bath. (Could be wrong) If they do then the areas hidden from view aren't getting derusted as well since electrolysis is line of sight and proximity sensitive. It is the best way to strip paint and do some light derusting. I've tried it and been amazed.

Does the dipping place offer a primer sealer bath or at least some means of addressing the inside inaccesable areas? (Rocker P's, Pillars, QP's) For visible areas epoxy primer is the best if followed by phosphoric treatment. (ZPhosphate) Epoxy makes the best barrier to keep moisture out during prolonged prep. Most other primers are permeable and can actually hold moisture if topcoated before drying. Zinc Chromate really needs to be topcoated with something impermeable and should not be relied upon for more than a day if you are shooting for 0 sheet rust under your paint. People do get away with less all the time but we are trying to save what precious little thin sheet metal we have left.

To my knowlege most primers need to be topcoated within three days for a good chemical bond. In hot climates this time can be shorter. After three days pass the primer needs to be scuffed before other coats follow. Epoxies can stay on for up to a year before they need to be stripped.

PPG has great .pdf docs regarding proper use and prep for all their products...

http://www.ppg.com/cr-refinish/phase1/frmSiteIndex.asp#

I'm no expert but I just stripped and repainted my Z. There was minimal rust underneath the paint which verified that the use of ZP and epoxy during the six month prep period worked. (Paint was 17 years old)

My2c

http://warbuddies.homestead.com/RestoHelp.html

[cbudvet]

Thanks for the information. I am pretty sure the dipping is an electrolysis process, at least I am pretty sure he mentioned something about it. I was going with the chemical bath vs. sandblasting because I was told it was easier on the metal and wouldn't deform the thin sheetmetal. I do really appreciate your responsed because it sounds like I should wait until I can save the money and try to get it done all at once. I am going to take the gas tank to them because it is small enough for me to handle. Thanks again. Carl

[jmanz6]

Some chemical dipping is done in a phosphoric acid solution. This will eat the rust, but not attack the metal as much as a stronger acid. The acid dip should leave a protective coating on the metal, however you MUST cover it quickly. The best option is to use a porfessional etching primer on the bare metal then coat that in an epoxy primer (PPG DP90). This is where your body work can start. If you have rust to repair, you can strip just the areas you will be working on and not have to worry about the rest of the car. Some chemical strippers will do the priming for you if you pay a little more. If oyu can't afford to do it all right now, I would suggest waiting until you can. You don't want to get all the rust off the car to have it sit and flash rust all to hell while you watch. Don't use the Autozone rattle cans for anything. That primer has been proven to be incompatible with many quality paints. If you prime with the cheap stuff, don't expect the top coat to stick...

[racebird1]

I would be a bit concerned about the areas that will get stripped and will not be able to get to and recoat. I agree that it can't sit long after stripping. When recoating you must etch the bear metal or it will all start to peel off after 6 months or so. So make sure you etch the metal or use a self etching primer. Also make sure it is a primer sealer so as not to absorb moisture thru the primer.

[a7dz]

I was advised by our automotive paint store to try this product. It is sweet to work with.

http://www.autobodybrands.com/primers/5425_x2k.html

It is a direct to metal epoxy fill primer or sealer.

Just my 2Cs

[sideshowbob]

That green self etch rattle can primer won't prevent corrosion in the slightest without a topcoat, you'll actually see the rust form under it in a short time. Best thing to do is wait until you can get it done all at once. For the body repairs, just do whatever welding/hammering/grinding you can now and spray with a rattle can lacquer or enamel right over the metal in places you go through the paint and don't do any filler until just before you're ready to paint.

[cbudvet]

Thanks again for everyones input. I am planning to work on the smaller projects (gas tank, etc). and wait on the major body stuff until I am better prepared financially to do it all at the same time. Carl.

[Corganx33]

go to autobody101.com and read up on what you can there, they are very helpful on doing work such as painting a car.

I did the similar to you. Am using an epoxy primer to seal the car after stripping

[mdbrandy]

go to autobody101.com and read up on what you can there, they are very helpful on doing work such as painting a car.

I did the similar to you. Am using an epoxy primer to seal the car after stripping

I'd also suggest:

http://autobodystore.com/forum/index.php

I've found a lot of good information there.