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Gotta love a turbo!
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Discussion Starter · #1 ·
I know, it's New Year's day and everyone is out doing something! Happy New Year! :welcome: :D

I sprayed the rear third of my frame last night with one coat of SPI epoxy primer, thinking I'd wait overnight to apply the second coat. Now it's 45° out there, besides the tech sheet says:

"Spray one coat and let it flash about 10 minutes at 70° degrees or higher. Then spray second coat for maximum corrosion protection. If one coat of epoxy is used wait 30 minutes before painting. With two coats of epoxy wait 60 minutes to paint."

Has my "window of opportunity" vanished for the second coat or am I covered under this other SPI blurb:

"This epoxy does not need to be sanded if painted over within 7 days. Always paint or primer over the epoxy within 7 days."

I'd like to get another coat on while my left-over mix is still stable...

Thanks!

Russ
 

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I believe you should be fine if second coat is done within the 7 days. If in doubt, all you would have to do is scuff it up before you apply your second coat, but I think your okay and still well within your window. And being its that cold, cure will probably be slowed a lot. In fact think you should try to keep it above 60 for awhile. But, why not just ask Barry K, since they are his products and get the scoop right from him, he'll know his products much better then I. You can go here and ask your question about spi products. Spi.forumup.org
or go to the southern polyurethanes website and call the number Barry gives. Customer service is something they take pride in, so he probably won't mind answering your question, even on new years day.
southernpolyurethanes.com
 

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Gotta love a turbo!
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Discussion Starter · #5 ·
Thanks! Recoated just fine like it was, even at 50° or so. I'll wait until tomorrow to fill scratches, dents, & grind marks, should be safe enough by then...

Russ
 

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KING OF BONDO
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Russ you should never ever ever ever ever ever ever ever ever, be spraying epoxy in that cold of a shop.. I am surprised neither of the 2 above told you that.. Epoxy is not like 2k, you cant shoot it and let it be cold, or even worse shoot it on ice cold metal.. It is a big no no.. BIG NO NO

Metal temp needs to be at least 60 degrees and the garage kept warm for at least 4 hours after it is sprayed..

I keep telling Barry he needs to put a huge disclaimer on the epoxy tech sheets just for this reason
 

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In fact think you should try to keep it above 60 for awhile.
Well alluded to it BK, I caught it. I gave links to Barry's site, and forum. I figured he would be best to give recommendations on use of his product. How do we know how long it was above 60 when he painted the first coat? he just said it got down to 45. Now is it going to cure if it wasn't in proper temps if he warms the area now if it did fall below 60 first time, or has cure stopped for good? He asked how long you can apply second coat, so I assumed he would wait till it warmed up again or could get it warmer. not spraying right away. Hoped he'd talk to Barry and could explain the whole situation. Guess when you make assumtions, sometimes you make an arse out of yourself and can't give perfect answers to everyones questions. Yes, that statement on sheets would be a good addition, since a lot don't know about how low temps will prevent cure, and many that do mention to stay above a certain temp are vague and don't give a reason why.
 

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KING OF BONDO
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Its metal temp guys... Air temp being 60 doesnt mean a hoot... It would only come into play if the garage was kept that temp all the time by heat.. Then you could take a guess as to the metal temp.. Bob is right of course, you dont need to shoot anything at those temps, but at least with 2k it would not be as bad

I look at it like this.. paint is like you and I.. It is comfortable at 70-75 degrees.. it can work in hotter temps, but put you and I in below 65 degree conditions and the majority of us are cold and dont work as well.. keep droping the temp and down goes our ability to accomplish task.. same for paint, colder it gets, the slower it cures up to the point where it wont cure at all.. Epoxy is even worse.. Its like an super skinny person that likes the hotter temps and cant stand the cold... Get that person in the temps S10's shop is and they are pretty much worthless.. Just plain to cold

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I am fully aware that metal temp is what counts. This is why infrared is used for heat(cure) lamps. It doesn't really warm the air, but it warms the object, ie the car body or objects in front of it. But if it fell below 45 and was 2nd coated at 50, that car was not above 60 degrees. And if it wasn't in the shop long above 60, even though the shop may be 60 like bk said, what you are painting very well may not be. Infrared heat lamps are pricey, and you would likely need quite a few for a whole frame or car, but they will warm up an object quickly as well as cure your primers, ect quicker, without running a lot to heat the shop and air. These benefits are why they are used in cure booths. If I had the money I would purchase a few, would be easier to keep what you are painting warm enough (your heating what really needs to be heated) and have cure when you have an uninsulated garage and live in a state that is often cold. A production shop without heat lamps would have a problem. The heat gets turned down at night to save money. So you go in next morning to a cold shop and vehicle and have a spot that needs to be primed. Often things get primed and painted in the same day. So you pull out the heat lamp and speed the cure.Heck if I won the lottery I'd have a nice huge heated insulated garage and infrared for curing. But most people don't, so we run into troubles keeping stuff warm enough for many hours and in the middle of summer fighting opposite conditions. And if you are not aware of exactly how a product is to be used, that can cause problems you probably aren't even aware is a problem.
 
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S10.... Let me set this straight. The metal temp is normally, in colder temps, at least 5-10 deg cooler than the air. The metal temp needs to be 60+ for several hours after spraying epoxy for it to cure. Total curing takes about 7 days, but the first 24 hours are the most important.

I understand that many people don't have an insulated, heated garage. If that is the case, and you cannot get the temps in that range, for that amount of time, you need to wait until you can.

Aaron
 

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Gotta love a turbo!
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Discussion Starter · #14 ·
adtkart said:
S10.... Let me set this straight. The metal temp is normally, in colder temps, at least 5-10 deg cooler than the air. The metal temp needs to be 60+ for several hours after spraying epoxy for it to cure. Total curing takes about 7 days, but the first 24 hours are the most important.

I understand that many people don't have an insulated, heated garage. If that is the case, and you cannot get the temps in that range, for that amount of time, you need to wait until you can.

Aaron
Too late now! When the first coat was applied it was maybe 60° ambient (4 pm). A little warmer in the garage, but the door was open... Second coat went on the next morning about 50° ambient. Both sprayed well and seemed to take, I've handled my panhard bar which was primed at the same time and it's not soft.

I'm not planning on doing anything to that area, I'll just be sanding and prepping the forward 2/3 of the frame. This old ride has been nothing but mistakes so far, I guess I can add another to the list! :spank:

Russ
 

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Gotta love a turbo!
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Discussion Starter · #17 ·
I've been reading this board for 2 years and don't remember anything being said about temperature affecting epoxy curing correctly. Had I remembered, I'd have searched it out. Besides this is a catalytic reaction, hence the "cure" shouldn't be affected, only the cure time. I'm not pressed for time here...

If the old saying "mistakes build character" is true, I should be, well, full of it!

Russ
 

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Not with epoxy.
You go below it's "cure" temp and it basically goes dormant untill the temp comes back up.
I have some mixed SPI in the fridge now,been there since Sept.
I'll pull it out in another month and let it warm up and spray it as a test.
Just consider yourself lucky with this one and you'll know better next time.
 

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KING OF BONDO
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A couple quotes from the master himself concerning epoxy and temps


BarryK said:
Epoxy is different they any other product with the cold.

2k primer you can spray out side when its 30 out and it will cure out as it warms up, same with the clears.

Not with epoxy, if sprayed at say 50 degrees it will flash off but could be 6 months to a year before it finishes kicking off and can cause major problems.

Cold weather applications:
Pre warm metal to 70 degree range.
Let epoxy induce in mixing cup for 30 minutes after mixed and then remix.
Spray a coat and let flash good and then second coat.
THE MOST important thing you can do is keep it at least 70 for two hours after you spray the epoxy and then let it get cold.

Barryk said:
It is a bad idea to store mixed epoxy in a freezer.
All epoxies react different to this but the curing process in some can cause a reaction and form alcohol or water and then never cure.

Epoxy is a weird duck with the way it is set up and cold temperatures.
It could work fine or it may 1/2 dry or it may never dry, you just can't say.

55 degrees scare me with my epoxy but has worked at that temp 50 degrees all bets are off as I have seen some real messes at that temp.
Sorry for your mishap S10..
 
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