Novice. The firewall (interior/exterior) and dash were stripped to bare metal and primered several years ago. Rust has resurfaced and I want to take steps to stop the rust from becoming too serious. Plan is as follows:

-Resurface area's mentioned to bare metal.
-Spray with metal etch, wash using dish soap, then rinse thoroughly.
-Spray couple coats of primer:*** Not clear whether I should use a Urethane, or Expoxy Primer. I was given a gallon of 2K urethane primer/surfacer, and 1 gal. of Enduro Expoxy primer, labels on both indicate manufactured by Kirker. I have no problem passing these primers on to someone else if indicated. Aware it best to stick w/ a particular manufacturers products threwout the project. Looking at PPG, or Dupont but need to do further research. Intend to prime within next few days. It will be few months while making body repairs before I start preping entire vehicle for painting. I would appreciate any suggestions, or input.

dave

 

I used PPG DPLF40 epoxy primer on my truck and loved it, then I primer/surfaced it wet on wet with K36. The PPG K36 primer surfacer I used said it was not for large areas of bare metal. I think epoxy is the way to go on bare metal though. ...

Check your P-SHEETS for putting epoxy over etch primer though. I read somewhere that epoxy over etch primers can cause problems and not really needed with good epoxies. Opinions and applications on this topic vary from one shop to the next . Good luck. jmo

 

Use a coat or two of epoxy over bare metal. If you need added build for some reason and easy of sanding, use the urethane over the epoxy. If the urethane is applied over the epoxy within its window, you will not need to sand the epoxy before coats of urethane primer surfacer. Epoxy will seal the metal from moisture and air/ provide good corrosion protection and have good adhesion to sanded or etched and clean metal. Epoxy is a little tougher to sand and may want to gum up the sandpaper and may be easier to sand wet. Cure time on epoxy is generally pretty wide, like a few days to a week or so. Check with your epoxy manufacturer. You can use bodyfiller over epoxy if needed also, without sanding if still in window, scuffing up first with 180 grit if past its time window. Urethane is somewhat porous, but typically has more build and is fairly easy to sand after a few hours or best overnight. If you want to go all out, epoxy reduced as a sealer and sprayed over the sanded urethane may provide a little advantage in chip resistance, hold out and gloss, but you will be perfectly fine painting over the sanded urethane also, but do use epoxy over all baremetal areas. Also keep in mind with 2k products like urethane and especially epoxy you need to have realitively warm temps, particularily the metal temp is what you need to be warm. You want to keep the metal temp above 60 or cure may stop and it may not continue curing when it warms up. 2K products cure by chemical crosslinking and the temps need to be maintained for at least several hours.

 

With the cool temps of late, looks like this task is becoming problematic. At this time only concerned about the area's noted, firewall and primarily the dash. Any opinion whether it possible to use a 125k portable forced air heater until vehicle and shop reach desired temp., shoot couple coats of primer, then set thermostat for the several hours for paint to set. If it requires maintaining the temp for matter of days for paint to set then will need to rethink, perhaps quick fix using fast drying primer.

Browsing online and came across a product 'epoxy primer sealer'. Kenseth17, not sure if this is same or simular to process mentioned in thread where epoxy is reduced to act as a sealer. Wonder if it would be less labor intensive if apply couple coats of the epoxy primer/sealer; or the epoxy primer, then 1 or 2 coats of the urethane. If understand correctly, when time to prep for painting in 3-4 months, it would be less labor intense sanding over urethane than the epoxy primer. Preping would consist of sanding, applying coat of the epoxy primer then prep by sanding again for painting.

Appreciate the information, thank you.

dave

 

Unbelieveable paint job. Do not have the history on the Kirker products, they have been setting for close to 1 yr. since given to me, do not know how long before that. Will check out other popular products and purchase fresh supply. Greg is pleased w/ PPG so intend to check their primers, and couple others brands. Tried the Southern polyurethane.com but unsuccessful. Using kerosene forced air heater is exactly the setup I have, sounds do able and can't wait to get started. Was very close to taking cutting torch to project, increasingly motivated now seeing some progress. Again, appreciate your time and information.

dave

 

http://southernpolyurethanes.com
I'd be concerned about how good the activators are after that amount of time. Possibly okay if kept sealed and stored in a cool dry place. The primers themselves I think should be okay. The activators can either harden up or just go bad or get seedy. You may want to try mixing a little of the primer up in the correct mix ratio and see if they will harden up.

 

I have experience only with PPG products and used used the their epoxy primer (greenish color) several times. Sometimes I needed fill so used their primer surfacer over it as soon as possible, sanded and then sealed with their sealer sprayed straight out of the can. I don't even paint during our "warm" California winters. Ha! Low 50's lately. Can tell you that once the cans of catalyst and hardner are opened they don't have much shelf life due to moisture absorption. Since those are where the real costs lie I don't paint until I can use at least the whole container that has been opened within the week of painting. Don't want to waste any by taking it down to the recycle center for disposal.

 

Came across web site for 'kustom shop' and appears they have quite a selection of online products, and only supplier found who carries the epoxy primer/sealer. Tempting, but not familiar with their product.
http://www.tcpglobal.com/kustomshop/kspepoprime.aspx

Couple manufacturers require telephone contact, Southern and couple others, will call and inquire tomorrow. Seems most of the local auto paint supplier only carry PPG. May go the PPG route, like the face to face; although finding sales person who knows his business is another matter. Appreciate the information.

dave

 

It won't be a problem at all calling BarryK from spi if you have any questions. He has his cell number right on the site if you need to call him. People do it all the time I guess, and he says he enjoys talking to people and answering there questions. I was a big ppg guy too, but been using it less often now that them and the other big names have gotten so expensive, and there are other good brands at better prices. PPG's DP epoxy primer use to be great stuff, and I used it a lot. Then it changed to dplf- lead free. I haven't used it since it changed. I've read a few people having problems with it, but not using it, I can not say. I just notice you said it was taken to bare metal years ago. Do you know what primer was put on it. I think I would plan on restripping it all and starting with the epoxy, or maybe your self etch first if absolutely needed followed by a good epoxy. If lacquer primer was used, time to restrip. If epoxy was the first time, then the rust must not of been properly removed or something not done right, cause with clean metal followed by epoxy it should of held up well.

 

Not clear what type primer was applied so currently in process of stripping the area's mentioned to bare metal then apply couple coats of epoxy primer. Intend to contact SPI tomorrow, have few questions and perhap they can provide some advice. Need to make selection soon. Appreciate the help.

dave