Finally getting to the point where I can start priming some parts again.
I have some open Grey primer 90% full, that has been sitting about 2 years.
And a gallon of unopened black also sitting around 2 years.
I heard that the activator that is open is ng after sitting that long.
Am I asking for trouble using paint/primer that has been sitting that long?

I see shops with tons of open cans for color mixing, I Imagine it must take years to use up some of the colors.

Thoughts?

 

Call the manufacturer or a supplier direct. That will tell you the real answer.

 

won't that answer always be "BUY More"

 

Do a test sample. If it drys as advertised, blow it! Do not ask the manufacturer. They are in the business of selling product. Secondly, if the catalyst is still fluid (not thickened), Generally it will be fine. If it is highly viscous, just buy a new bottle of hardener.

 

I’ve been painting for nearly 30 years in a production environment. I’ve seen a lot of stuff sit around for a lot of years and still be used successfully. Usually when a product goes bad, it will be obvious. Hardeners that have been opened will eventually harden. Epoxy activator/hardener is the only product I’ve ever seen consistently go bad on the shelf. Most paints, primers, clears, etc have basically an indefinite shelf life as long as they’re sealed properly. I would get some activator and send it regardless of what the tech sheet or manufacturer says. They always want you to buy more.

 

A decent rep will tell you the story and should be able to provide the data sheet for the product. That will have the info. I wouldn't halfass this. If the color lifts that will cause a lot of pain.

Use your own discretion but I'd start there.

 

If you're going to use the paint on the exterior of the car, I'd just buy some new primer. You'd never forgive yourself if you used the old primer and the paint failed or looked bad.

 

Most DIY guys and even small, low volume shops don't have easy access to manufacturer paint reps. The TDS sheets are chock full of valuable information, but they also serve as a CYA for the manufacturers. And never, ever, ever trust info given to you by the guy behind the sales counter at a jobber.

If the primer mixes up and looks fine, I'd bet my warranty that it's fine. I wouldn't trust old epoxy hardener though.

 

This is probably the best way to settle this debate. Get some new hardener, mix a small batch and spray a sample. If it does what it's supposed to do, full send it.

 

Google will get you the info. It's not impossible.

 

who said something is impossible??

google will also get you a lot of bad info. As will asking groups on the internet.

I’ve been painting. running paint shops, training painters, assisting with r&d for paint manufacturers, etc. for almost 30 years. I know what works and doesn’t work better than most paint reps.

I’m not just trying to argue, I'm just saying that a salesman isn’t the best place to go to ask if you should use the product you have or buy new product.

 

I’m kinda wishing the OP was in my neighborhood. I’d be like “Oh yeah, you need to dispose of that stuff right away! Here, I’ll safely and properly take care of that for you!”😂. Of course then again, I don’t go by the numbers on milk cartons either, my nose determines whether or not I drink it. Life is short, Roll the dice!!

 

I chickened out and got a qt of mp170
Since I spent over 40 hrs stripping the fender down due to rust under the edp coating.
I'll try the leftovers on some of the under side parts.

 

Make sure you give us an after pic too once the fender is painted and mounted.👍