Sprayed epoxy for the first time, have a few questions?

rustover

rustover

Member
Today I finally sprayed SPI epoxy. Its actually the first time I have ever sprayed anything with an hvlp. I sprayed the drivers door shell of my 72 Camaro. I also spray a few small brackets.

I induced the epoxy and let it sit for at least an hour. Meanwhile I cleaned everything with SPI 710. I know now that I should have used the 700 first, and will on the next one. I will say I am amazed at how well the metal cleaned up with the 710. The parts were freshly blasted and after I cleaned them the metal really looked good.

I have never sprayed anything, but when I first started out, on my first coat which was light I thought, I would get these craters that looked like cheese. I have read on the forum that this happens with white, when you lay it on heavy. It was the first coat, so I thought I would let it flash and try a second. If it got worse I would stop. On the second coat those cheese holes seemed to fill in and all was good. I let the second coat flash, mixed up some more and went to eat. After about an hour I put on a third coat. I thought on my coats were light. The second coat everything looked great, but I had a few light spots in some areas. I know these door shells must be one of the most aggravating things to spray, because of the brace that runs down the middle. I had a time trying to get paint in these areas. I got one sag at the striker area that I will fix after I skin it. There are a few places that I just could not get paint in. I'm thinking of trying my airbrush on those tomorrow after work.

After it was all said and done I used half a quart. This is 32 ounces and I have 4 left over. Does that sound right? I know some probably got wasted by me trying to get in all the nooks and crannies, Or did I over do it?

Some things I need to work on:

1- Neatness, spilt some paint, got it on my glove, then got it on other stuff

2- Cleaning the spray gun. For now I used a half of can of Sem Spray Gun Cleaner. Too expensive.

3- Next time tape the bottom of my shoes.

Thanks for the help. Here are some pics:







 
With the info given, it sounds like fish eye, which may indicate improper use of W&G remover.

The w&g remover is a slow evaporating solvent, as it is intended to "float" any impurities to the surface where it can be wiped off. Most manufacturers of these type products recommend using one rag, damp with the solvent, to wipe a small area of the panel, and after a few seconds to do its thing, a different clean dry rag to wipe it off. Do a small area at a time, and remember karate kid.....wax on, wax off. Same principle. Sometimes more than one cleaning session is a good "insurance" policy, given the cost of paint products. For the size of the area that you are cleaning at one time, you want the "area" to be covered without drying, so you have time to come back and wipe the impurities off while the W&G remover is still liquid. If it's drying too quickly, reduce size or use more W&G remover on application rag.

If part of your process that produced the "cheese" was to wipe it on and wait for the w&g remover to "flash", it is just leaving the impurities there on the panel. I have heard of others use lacquer thinner for cleaning, but typically it evaporates too quickly for not enough time to float all of the impurities up for effective removal..


Inner door is looking good, btw... :encouragement:
 
Every now and then I'll trip and get the fisheye kinda look from my gun getting too close and the air turbulence causing an odd ripple.

On the note of actual fisheye I have gotten them when not letting the wgr flash off long enough and also from missing a spot or even one day I was rushing and completely forgot to wgr.....

In any case I always sand down and start over in that spot.

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Every now and then I'll trip and get the fisheye kinda look from my gun getting too close and the air turbulence causing an odd ripple.

On the note of actual fisheye I have gotten them when not letting the wgr flash off long enough and also from missing a spot or even one day I was rushing and completely forgot to wgr.....

In any case I always sand down and start over in that spot.
 
Whenever something is sand blasted theres 2 things i dont do. Never put your bare hands on raw metal and I never clean a sand blasted surface, I blow the loose sand off but that's all. Its a very rough surface and all you do is trap the impurities or create more with your rag. And i always get it in epoxy within 24 hours of being blasted . The moment its finished with blasting that is the cleanest it will be and its a going to start collecting impurities so the sooner you shoot it the better. I have never had a problem with this method
If feel you must clean it Ide let it sit after cleaning for at least an hour


I would consider calling Barry as well :)

Hope this helps

- - - Updated - - -

Whenever something is sand blasted theres 2 things i dont do. Never put your bare hands on raw metal and I never clean a sand blasted surface, I blow the loose sand off but that's all. Its a very rough surface and all you do is trap the impurities or create more with your rag. And i always get it in epoxy within 24 hours of being blasted . The moment its finished with blasting that is the cleanest it will be and its a going to start collecting impurities so the sooner you shoot it the better. I have never had a problem with this method
If feel you must clean it Ide let it sit after cleaning for at least an hour


I would consider calling Barry as well :)

Hope this helps
 
Whenever something is sand blasted theres 2 things i dont do. Never put your bare hands on raw metal and I never clean a sand blasted surface, I blow the loose sand off but that's all. Its a very rough surface and all you do is trap the impurities or create more with your rag. And i always get it in epoxy within 24 hours of being blasted . The moment its finished with blasting that is the cleanest it will be and its a going to start collecting impurities so the sooner you shoot it the better. I have never had a problem with this method
If feel you must clean it Ide let it sit after cleaning for at least an hour


I would consider calling Barry as well :)

Hope this helps
 
Thanks guys. I did blast and coat everything the same day. I used a sprayer with the wg remover and several towels until everything was clean. I then took a new red scuff pad and lightly removed any fuzzies from the rag while using a blow gun.

If it was fish eyes would the second coat have filled them or would they have got worse? I think I may have just got too close to the substrate.

Can't wait to spray something else now.
 
Airbrusharthart;37636 said:
Whenever something is sand blasted theres 2 things i dont do. Never put your bare hands on raw metal and I never clean a sand blasted surface, I blow the loose sand off but that's all. Its a very rough surface and all you do is trap the impurities or create more with your rag. And i always get it in epoxy within 24 hours of being blasted . The moment its finished with blasting that is the cleanest it will be and its a going to start collecting impurities so the sooner you shoot it the better. I have never had a problem with this method
If feel you must clean it Ide let it sit after cleaning for at least an hour


I would consider calling Barry as well :)

Hope this helps
Click to expand...

I've seen primer peel right off of blasted steel when the abrasive has been recycled and it wasn't cleaned before primer was applied. If you are using new abrasive for all your blasting the chances of problems diminish. The thing about recycled abrasive is all the contaminants get mixed into the abrasive and get hammered into the surface of the metal.

- - - Updated - - -

Airbrusharthart;37636 said:
Whenever something is sand blasted theres 2 things i dont do. Never put your bare hands on raw metal and I never clean a sand blasted surface, I blow the loose sand off but that's all. Its a very rough surface and all you do is trap the impurities or create more with your rag. And i always get it in epoxy within 24 hours of being blasted . The moment its finished with blasting that is the cleanest it will be and its a going to start collecting impurities so the sooner you shoot it the better. I have never had a problem with this method
If feel you must clean it Ide let it sit after cleaning for at least an hour


I would consider calling Barry as well :)

Hope this helps
Click to expand...

I've seen primer peel right off of blasted steel when the abrasive has been recycled and it wasn't cleaned before primer was applied. If you are using new abrasive for all your blasting the chances of problems diminish. The thing about recycled abrasive is all the contaminants get mixed into the abrasive and get hammered into the surface of the metal.
 
It's happens With all colors. It's sensitive stuff . It was a big learning curve for me to get it to lay down without a single spot that you describe. Trust me. You can recreate the problem.

Spray it on any surface and blow on it lightly it Will " fish eye " every time.

I was told it's because their are no fillers . Makes for a better product. but its harder to lay down consistently

- - - Updated - - -

It's happens With all colors. It's sensitive stuff . It was a big learning curve for me to get it to lay down without a single spot that you describe. Trust me. You can recreate the problem.

Spray it on any surface and blow on it lightly it Will " fish eye " every time.

I was told it's because their are no fillers . Makes for a better product. but its harder to lay down consistently
 
Good point bob, I also don't use recycled media. Just curious was it Spi epoxy that peeled?
 
nope not SPI, but it can happen with any brand if the contamination is bad enough. When a person is blasting an engine compartment, underside, interior....any remaining grease, armor all, seam sealer, roadtar, body shutz, sound deadener, oils....it all gets mixed in with the abrasive if you're recycling it and really gets hammered into the metal. Unless you really preclean it well before blasting.
 
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