Do I need two primers

I am trying to put the finishing touches on the inside of my canopy skirt, this is the first fiberglass work I have done. I have a done the clear West Systems epoxy coat to fill the tiny holes and this is looking good.

Now as I understand it I want a coat of primer to block sand to show where the flaws are located. Repeat until you have the finish you want. A lot of the write ups talk about using and "Epoxy Primer" PPG DPLF is one DanH uses. This stuff is expensive, not nearly as expensive as the K36 I already bought thinking that was the stuff I wanted to use.

I only want to protect the glass work until I can have a professional do the painting in a year or so after flying, maybe two. Since I have more K36 than I will ever use, can I just use this for the whole process or is the epoxy primer needed before the K36 goes on. I don't know if there is a cheaper epoxy primer or not, online the DPLF stuff is $55 a quart then I would need the catalyst.

Thanks for any help, most of the writes up I have read online assume someone knows what things like Guide Coat, Tie coat etc mean, but this is all Greek to me and I am trying to understand the process.

Cheers

you could use your K36 on the raw glass.. it works great! plus its MUCH easier to sand than epoxy (since epoxy is not a build primer)

Best results, DPLF or other epoxy primer first.. then K36 or other high build 2K primer over that. Be mindful of dry times and adhesion windows.. DPLF has a claimed window for top coating of 7 days at 70 degrees, with out sanding between coatings. However if you must scuff the epoxy, PPG and all the others recommend that you apply a coat of the epoxy to the scuffed (and presumably cured) older coating.

K36 or other Urethane 2k primers all require sanding between application windows. You dont have to sand between coats the day you apply them, but if you wait a day you must suff (and clean it) between coats.

Mike,

I'am working on my skirt now also not ready for primer yet but I understand that epoxy primer is very hard to sand and if you are going to sand it back off I would think that the K36 would work just fine. I would like to know myself as I will need to prime mine soon. I have some nasons two part primer that I was planning on using I have it on hand so I think I will try it. I don't know about you but I am about ready to move on to something else I hate taking two baths a day I have sanding dust everywhere

DPLF, while not required under K36, is suggested as it will enhance the adhesion. There is a recoat window on the DP products that must be adhered to, by the way.

Brad Simmons
Airframes Inc.
Milan, TN

primer

Randolph Rand o plate epoxy primer works better than PPG for me on fiberglas. Then the PPG high build primer. I think the Randolph is a bit cheaper than PPG.