i have started using spi epoxy entirely through my process. last project i went to about 30 days on my final prime so with spi epoxy so i 180 blocked it reprimed with two coats prepped with 400 4 days later sealed with 20 percent reduced epoxy based and cleared worked great. i typically like to block through the grits 150,320,500 then seal and shoot what i used to do before all epoxy. i understand there is alot of variables . i understand after a while its cured where it needs that strong sand scratch to bite because its lost its chemical adeshion. since im sealing with epoxy do i have a little more time than the 14 day window if kept inside? just curious so i could maybe get it done in one prime session basically. im usually sealing with 20 percent reduced epoxy letting flash overnight then base coating.
epoxy ready for sealer time.
- Thread starter zachm
- Start date
Sanding epoxy with 180 yes 14 days or longer is a nonissue as long as the epoxy you apply is reduced by less than 25%.
Of course, in a perfect world, I like the idea of the first coat being shot at 1:1 and then the second coat reduced for the slickness you want, but past testing does not confirm my opinion.
Of course, in a perfect world, I like the idea of the first coat being shot at 1:1 and then the second coat reduced for the slickness you want, but past testing does not confirm my opinion.
Lizer
Mad Scientist
You have a ton of unnecessary steps IMO. Reduced epoxy has a shorter cure window, and the window is 7 days for epoxy, not 14 days.
Once you reprimed and sanded with 400 you were ready for base, there's no need to shoot a sealer over fresh blocked epoxy providing everything was uniform in color and no sand thru's somewhere.
You don't need to block through all those grits either. It sounds like you were referring to high build urethane and then have since switched to epoxy only? Your post is a bit hard to follow.
Once you reprimed and sanded with 400 you were ready for base, there's no need to shoot a sealer over fresh blocked epoxy providing everything was uniform in color and no sand thru's somewhere.
You don't need to block through all those grits either. It sounds like you were referring to high build urethane and then have since switched to epoxy only? Your post is a bit hard to follow.
Awesome thanks for the response Barry. So basically anything g after 14 days you would reccomend the 180 and reprime for safety sake. And max ashesion? I might have to get where I just do a “final prime” then which isn’t a big deal. If I can’t get it all blocked out within 14 days to a finish grit.
I use the epoxy as a high build. Non reduced. Usually by the time I finish blocking everything it’s around that 14 to 30 day mark.
'68 Coronet R/T
Oldtimer
When you guys are using straight epoxy primer, do you still use a 1.4 tip when spraying?
I would hope they are!
Everything in tech guide is based on 1.4 and no reason ever to use a 1.8 as i.8 or higher is for 2 k primers.
'68 Coronet R/T
Oldtimer
Thanks Barry. I am wanting to keep my GTX in straight epoxy but wasn't sure about this.
I'll shoot another coat today and when cured block sand it with 180 grit and see how it turns out.