Shelf life of Sherman Williams Primer

JDBoston · #1 04-21-2020, 11:04 AM

I have restarted work on my 14A, and know that Sherman Williams mentions a three year shelf life for their wash primer. Has anyone had success using older primer perhaps 4-5 years old or should I do something else? SEM Rattle can is the other option, but I am in the process of dimpling all the skins for the tailcone so I have quite a bit of surface area to deal with.

Thanks

Dean Pichon · #2 04-21-2020, 01:40 PM

If your paint is only a year or two past its expiration date, I would mix up a small batch to confirm that it cures properly. If the containers were well sealed and the contents appear ok, you should have no problem. If you are still concerned, you could do a tape adhesion test (ASTM D3359 or similar) to confirm that it sticks well to the substrate (aluminum?).

Good luck,

Dean

wirejock · #3 04-21-2020, 03:38 PM

Sure hope so. I sprayed lots of parts past the date. Last one needed to be stripped to get bare metal. Took me all day to get it off!

I agree with Dean. Test of scrap to be sure.

goatflieg · #4 04-22-2020, 03:52 AM

I've already thrown away $$$$ in expired S-W paint. I was a fool to stock up early, and I've still got some wash primer and primer that I'll have to test shoot. Not taking chances on the top coats; already replaced some stock.

wirejock · #5 04-22-2020, 10:02 AM

I've moved to Kirker paints. If I build another, it will be my paint for interior and exterior.
Enduro Prime is an epoxy primer. Tough. Comes in white, gray and black. Perfect for dual use. Primer and interior color in one. Easy to spray and touch up. Cheap.
I'm equally impressed with their UltraGlo Single Stage. Beautiful finish coat.

JDBoston · #6 04-22-2020, 10:04 AM

Just to be clear to people (and thanks for the suggestions so far) this is for the interior, not priming to paint. I am going to see if I can use what I have because I have been happy with the wash primer so far as well as the SEM rattle cans at least for the use I have.

wirejock · #7 04-22-2020, 11:34 AM

Quote:

Originally Posted by JDBoston

Just to be clear to people (and thanks for the suggestions so far) this is for the interior, not priming to paint. I am going to see if I can use what I have because I have been happy with the wash primer so far as well as the SEM rattle cans at least for the use I have.

Ok. Let's try again
I sprayed interior parts P60G2 then Jet Flex SB within a 30 minute window. I would still use P60G2 on the airframe. However, I would use Kirker Enduro Prime as an interior paint with no primer if I did it again. Colors are virtually the same. Flat gray and black. I could achieve the same look with one paint, save weight, cost and have an epoxy interior finish. Quarts are about 1/2 the cost as SW paint.

JDBoston · #8 04-22-2020, 11:36 AM

Quote:

Originally Posted by wirejock

Ok. Let's try again
I sprayed interior parts P60G2 then Jet Flex SB within a 30 minute window. I would still use P60G2 on the airframe. However, I would use Kirker Enduro Prime as an interior paint with no primer if I did it again. Colors are virtually the same. Flat gray and black. I could achieve the same look with one paint, save weight, cost and have an epoxy interior finish. Quarts are about 1/2 the cost as SW paint.

Now I understand what you are saying. Thanks!