I've acquired several dozen 8 oz cans (not spray) of the original Pactra Formula U polyurethane in a buncha colors, still liquid.
I'm not at all familiar with it.
Good stuff? Bad stuff?
If good, is there a suitable thinner currently available for it?

I think it was OOP for a while, but there's an online HS selling 3 1/2 oz cans of Pactra Formula U - over $31/can!
Another lists spray cans so I guess its back.
Don't know if it's the same stuff or not.

Thanks.

Terry

Update: ckd again - it's $31/ctn of 6 

I have acetone so I can try it if F U (pardon the expression) can be recommended.
Also found some old posts elsewhere saying "paint thinner", so'll probably work.

Terry

p.s. - discovered "thinner" is for lacquer; reducer for others, like polyurethanes.
Live and learn.

p.p.s. - Opened a can to try it; waiting for it to dry.
BUT - tried to clean the brush in acetone - a total bust - didn't even discolor the acetone.
Lived longer, learned a little more.  

Not sure but I think its a enamel so it would need reducer not thinner

Not sure but I think its a enamel so it would need reducer not thinner

  Its a one-part enamel and as I recall, turpentine or "paint thinner" works, nothing exotic is required, for sure.

   I used a fair bit of this back in the day. The only issue I ever had was that the gloss was inconsistent from color to color, and the clear was amber. It also had a tendency to remain rubbery, depending on the color.

   Brett

I used it years ago and my experience with it was similar to Brett's, inconsistent drying led to soft areas. You may want to make up some test pieces before putting it on your plane to avoid starting another thread titled "removing Formula U from my plane".

I have recently returned to C/L and building. I still have lots of Pactra Formula U left from when I bought up big in a closing down sale (due to the owner's terminal illness). Along with many other products for basis of comparison, I have used Pactra Formula U a lot. I like it. It is a superb paint, but like all paint products, you need to be aware of its characteristics.

I originally had the proper Pactra Forumula U thinner along with the Pactra Prep undercoat product and its thinner -which is a  lacquer & lacquer thinners.

Thinners

Pactra Formula U is a polyurethane enamel. IME enamel thinner proved the best substitute for the original Pactra Formula U thinners. I was spraying using an Iwata cabinet maker's gun. It works as well as the original thinners for spraying. But buy enamel thinner intended for spraying, not cheaper GP (general purpose) thinner (which is also an enamel thinner) but low quality. It'll work, but not as well and the price difference is worth it for the finish and spray characteristics the higher quality thinners will offer. Cheaper GP thinners is fine for cleanup.

Spraying with Pactra Formula U

Three things to keep salient in mind.

1. Light coats. If you're not achieving the opacity you want in a single coat or second coat, don't persevere with further application or you will get a wet coat, sags and run/s. Let the first and immediate subsequent second coat dry, then come back and recoat in the time period according to the instructions on the can. In the particular with Forumula U, do try to avoid a wet coat and runs. Why? Pactra Formula U is great paint. It's completely fuelproof and presents a deep lustre protective finish will will keep for 20 years. But, it dries as hard as a rock. Sanding it back really is a PITA. So . . . for the opacity you want, the rule is . . . light coats.

2. Practice on scrap first until you have the pressure and thinning ratio right for your weather conditions. Don't spray when its very hot or hot 'n humid if you can avoid it, as this will significantly affect the flash time of the paint and thus working time of the paint, particularly important if you want to apply a second coat and it's a larger model.

3. I've never found it to be any good for brush application. No matter the thinning ratio, it just sets up too fast and you'll get that dry coat look with a brush. Spray application only.

Hope those tips help.

IMHO.

If I couldn't get Formula U thinner, I wouldn't use the product.

But that"s me.

Edited for spelling.