How to treat bare metal sand through

hanzo111

Promoted Users
Blasted the truck
Washed
Water borne cleaner
SPI epoxy 2 coats
Body fill skim coat
3 coats of 2k primer

I’m done blocking and now have a few bare metal burn through spots.
Before someone suggests epoxy, I lost my temperature window last week. my barn will have a low of 55 at best in the evening's with 78 as the high.

Can I get away with 2k? Or should I leave bare and rely on my reduced epoxy as a sealer?
 
Good question, I should have mentioned.

5 of 6 spots total.
Smallest the size of a dime
Largest size of silver dollar
 
It's pretty much a given that anyone doing this work has to invest in heat. We've seen this over and over. Don't try to get around it, it will surely bite you in the butt.
 
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I was actually just discussing this with Barry yesterday.

My protocol—which he confirmed as good: Spray a double coat of epoxy on the bare metal spots around midday. Push it out into the sun so it gets at least three hours of warmth and UV. Even direct sun on a cool day will still really heat up a panel.
If you can only spray in the evenings then I’d first suggest investing in an Infratech 1500W medium wave infrared curing lamp. If not then a heat lamp would be your next best source.

My specific question was if my infrared lamp would close my open window too much, which it wouldn’t. That was when I asked him if acceleration from sun was sufficient and he said three hours was perfect.
 
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...As long as it can get that it will be completely fine, even if your night time temps get cold. It gets cold at night here in MI too but is usually a few degrees warmer in the shop...

It might be asking for trouble to put this out as a blanket statement. Sometimes Barry's privately given advice is tailored to individual users and situations. I want to hear it straight from the man @Barry , and if I'm wrong, I will apologize and delete this post if necessary. Until then, here is the text of the Tech Manual in regards to cold weather:
Cold Weather:
In cold shop conditions this primer can and will go dormant. Keep heat on the car for 24 hours after spraying with an absolute minimum temperature of 65 degrees. Also, when it's cold it will help to mix the primer and let it induce 60 minutes before spraying. Application of any epoxy in cold weather can destroy a paint job. There is no way to accelerate the curing process. Bottom line is if the car metal or primer contents cannot be kept at 65 degrees or higher as well as the shop temperature for the next 24 hours after spraying, DO NOT spray our epoxy as you may end up having to redo all your hard work. Also, temperature of the epoxy in the can is just as important so store the epoxy in a warm place for at least 24 hours before spraying. For $20 you can buy a laser temperature gun to take readings of the can and the car panels, and this will save you from guessing. Once again if you have any questions regarding the application of SPI Epoxy Primer in cold weather please call us first. Metal temperature when you spray epoxy is critical and must be at least 65 degrees as well as the contents of the epoxy and activator cans!
 
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UV light accelerates the cure so getting several hours of sunlight on something helps. Because the intensity and amount of sunlight varies around the Country there is no set answer to how long in the sun to equal 24 hours indoors @ 70 degrees. 2 hours in Phoenix would probably be the equivalent of 6 hours or more in Michigan. Suffice to say that getting UV light on the panel will help accelerate the cure. Hanzo being in Maryland, this time of year would be "safe" if he could get it out in the sun for 4 or more hours. At least that is my guess. Waiting for @Barry to give us the authoritative info. :)
 
Personally, I wouldn't take the chance. Also it's pretty unfair to keep putting Barry in the middle of issues he doesn't need to be in. He has already outlined what needs, or doesn't need to be done. Either use what he's already stated, or don't.

Maybe it's just the comfort of knowing that in six months or a year if your paint fails, you'll have a fall guy to blame rather than yourself for not doing what you should have done from the start.
 
UV light accelerates the cure so getting several hours of sunlight on something helps. Because the intensity and amount of sunlight varies around the Country there is no set answer to how long in the sun to equal 24 hours indoors @ 70 degrees. 2 hours in Phoenix would probably be the equivalent of 6 hours or more in Michigan. Suffice to say that getting UV light on the panel will help accelerate the cure. Hanzo being in Maryland, this time of year would be "safe" if he could get it out in the sun for 4 or more hours. At least that is my guess. Waiting for @Barry to give us the authoritative info. :)
if hes on the east side, we stay a little warmer a little longer because the water is still warm. i bet we dont have frost before nov, and could still see 90 in the next few weeks. i do have to say, this week has been nice. i think the 100 temps are over.
 
Personally, I wouldn't take the chance. Also it's pretty unfair to keep putting Barry in the middle of issues he doesn't need to be in. He has already outlined what needs, or doesn't need to be done. Either use what he's already stated, or don't.
I'll keep my mouth shut from now on.
 
Personally, I wouldn't take the chance. Also it's pretty unfair to keep putting Barry in the middle of issues he doesn't need to be in. He has already outlined what needs, or doesn't need to be done. Either use what he's already stated, or don't.

I'd rather let Barry speak for himself if he thinks we're bothering him too much. I think he's a big boy now and doesn't need protection.

I'll say it again, in my opinion, some of the advice given over the tech line is tailored to specific individuals and situations, and might not be suitable as public advice. I think it's fair to ask for clarification on this matter.
 
The only reason I shared it in this case is because the OP’s use case is exactly like mine, not a blanket statement, and it was information given to me just yesterday. That being said, the tech sheets are written overboard to be safe, and I do the same thing when writing tech sheets for my own products.

It’s also important to state that when the temps get cool at night I move my epoxy into the house. Then when I spray epoxy it’s always warm. It’s really important for the epoxy itself to be warm. In the cooler fall months I’ll also put the panel out in the sun for 30 min or so and it will warm up a lot for spraying.

On the other hand, I am posting this publicly and don’t want to create problems for the B man so maybe I should have shared the info in PM. Because somebody else who might not have the same situation could interpret it wrongly.
 
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You'd be surpised at what temps those 500W twin halogen lights can produce. I use those on a single panel or small parts for epoxy when the weather start to cool off. Using an infared temp gauge, usually the metal stays in the 80 degree range.
 

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Tonight I had my infrared lamp on a hood that I sprayed epoxy on earlier today. The lamp can only cover about a quarter of the hood at a time and it was on the hood for about 30 min. The epoxy there was noticeably harder than the epoxy on the rest of the hood, which still felt soft.

I move the lamp around on panels until the entire panel can get some exposure.
 
I fixed the issue. Should have thought about it before. I built 3 green houses and this is no different.
  1. mix warm epoxy and activator (room temp 75 degrees)
  2. warm panel with chicken heat lamps
  3. 73 degrees day time temps
  4. let epoxy flash all day
  5. place 2 poles across the top of the truck bed in question
  6. drape green house plastic (new) over poles. plastic doesn't touch newly primed metal
  7. place electric radiator heater under truck bed maintaining 80 degrees all evening.
thanks for the help
 
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