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Rattle Can Epoxy

#1
I'm probably going to get blasted for even asking this question - but here goes. I'm block sanding the high build primer and have sanded through a couple of very small areas down to the metal. Is it a mortal sin to just hit those areas with a rattle can epoxy rather than mixing up a batch of the real stuff? Be nice now.
 
#3
Eastwood has an epoxy with an activator in it now. One you pop it you gotta use the whole can. I noticed they had it with the weld thru primer from spray max as well. Those would be the only kind I would consider if I ran out of epoxy and would have to use something. At least there is an activator so its not just the standard acrylic enamel they call epoxy.
 

jlcustomz

evil painter
#10
Saying hell no was being nice. I'm posting a pic I've showed before of using rattle can products as what was supposed to be temporary paint for custom steel ground effects. I buffed the rattle can paint to look near as good as bc/cc put it quickly failed, primer on galvanealed metal first. This was partly an experiment for other's benefit that either couldn't paint or were between paint booth access like I was.

If you need to speed up drying time of spots of epoxy, you can use a simple screw in 250 watt infared bulb in a simple clamp on fixture after the epoxy flashes off as long as you use an infared temperature gauge to check metal temps . I'd start under 110 degrees & later move closer . 130 degrees & slightly higher can be safe a few hours later. Get too close with bulb & reach above approx 170 & you'll be sanding bubbles off. Takes a little getting used to the feel of using infared heat, but the IR rays cure stuff faster than heat alone & help shrinkage to occur faster. IR heat reaching concrete will warm it & extend air temps higher sometimes many hours later, even with air leaks in room. I mentioned clamp on fixtures & screw in bulbs as a lowest cost starting point, but there are many better affordable options such as pic from tractor supply store. I gave approx temp numbers & not much on time frame. You need to constantly monitor temps with IR gun till you learn how your heat setup reacts. One you reach peak temp after sometimes just a few minutes, it won't rise much above that. Lastly , like anything else, do at your own risk.
 

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jlcustomz

evil painter
#11
Another point to make to anybody about using epoxy is don't be lazy. While at first the induction time, temps, & wait till using other products dry times & what not can seem to be an absolute pain in the ass, particularly for working on something in time frames of the night time / weekend user, thinking production minded ,planning ahead, managing projects or different sections of projects together, & using the benefit of epoxy pot life make it seem much easier.
Thinking production minded with epoxy during bodywork can include straining & pouring epoxy to wanted 1 to 2 part fill line of a few mixing cups & capping them to add activator later. Stirring a gal of epoxy, especially one that you let sit around can be a pain & require a power stirrer in drill, grabbing a small container that has mildly settled & stirring with a stick is so easy. Having a 2 to 5 day pot life from premixed container is another reason not to be lazy about using it. May want a splash of reducer toward the later pot life use.
Don't forget product temps. I bring some sealed up product into house or work office this time of year.
Just a few thoughts & reminder to self.....:rolleyes:
 

Slofut

Active Member
#12
New epoxy cans I roll around on the shop floor. As long as the lids are on tight. I just push 'em around as I'm doing other stuff until I need to mix. You'd be surprised how well it works. :D
Also I have a couple Finex 1000 mini guns with large caps, for my weekend work and single panels I can mix small amounts easily and rarely have any waste. These spouts are your friend, been using them forever, very little waste. 58101767844__D080E76D-E8AB-4189-BC72-13DAF00623EF.JPG
 
#13
I don't want to drag this post out forever but let me explain a little better what's going on. I've done the blocking and have a few spots to go over and shoot a little more high build on the car. Some of the spots needing more high build have been sanded to bare steel. When I'm done blocking this second application of high build the car will get a coat of epoxy sealer.

Here's the question - those spots that are down to bare steel now will have a layer of high build between the steel and epoxy sealer coat. Is that ok? My initial question was about a quick and easy way to re-coat the bare steel with epoxy. So, should I be shooting SPI epoxy over those few bare spots I have now before re-applying the high build? I'm talking about little 2" slivers along an edge or a spot no larger than a quarter here and there.
 
#15
I don't want to drag this post out forever but let me explain a little better what's going on. I've done the blocking and have a few spots to go over and shoot a little more high build on the car. Some of the spots needing more high build have been sanded to bare steel. When I'm done blocking this second application of high build the car will get a coat of epoxy sealer.

Here's the question - those spots that are down to bare steel now will have a layer of high build between the steel and epoxy sealer coat. Is that ok? My initial question was about a quick and easy way to re-coat the bare steel with epoxy. So, should I be shooting SPI epoxy over those few bare spots I have now before re-applying the high build? I'm talking about little 2" slivers along an edge or a spot no larger than a quarter here and there.
I dont know if you will find an answer here. You are supposed to put the epoxy over an 80 grit scratch coat direct to bare steel. So no matter what you do, you are going to be wrong. You will either be spraying epoxy over portions which are high build and not to bare steel, or you are going to put polyurethane over bare metal. Do you sand back the epoxy over the hi build until you find the bare steel again, or just consider it the seal coat?
Sounds to me you should just seal the car with the epoxy since the cut epoxy is going to be better than anything you get in a rattle can. Maybe mix your paint at 1:1: .5 hit the bare spots and then put the rest of the reducer in for the seal.
 
#16
I don't want to drag this post out forever but let me explain a little better what's going on. I've done the blocking and have a few spots to go over and shoot a little more high build on the car. Some of the spots needing more high build have been sanded to bare steel. When I'm done blocking this second application of high build the car will get a coat of epoxy sealer.

Here's the question - those spots that are down to bare steel now will have a layer of high build between the steel and epoxy sealer coat. Is that ok? My initial question was about a quick and easy way to re-coat the bare steel with epoxy. So, should I be shooting SPI epoxy over those few bare spots I have now before re-applying the high build? I'm talking about little 2" slivers along an edge or a spot no larger than a quarter here and there.
As soon as you mention "rattle can" everything in me goes into panic mode. LOL
I suggest you shoot your SPI epoxy sealer coat and then carefully inspect those areas you are worried about. If you can see them after the sealer is applied they will show later in your paint job as well.
All is not lost however because you can wet sand the epoxy sealer prior to painting. If you fear they will show, maybe shoot a coat of epoxy mixed 1:1 and just plan on wet sanding before your color coat.
 
#17
I'm just not making myself clear. I've given up on the idea of using anything in a rattle can. I will only be shooting SPI epoxy. If I go ahead right now and shoot another coat of high build I'll be shooting that over bare steel in a couple of very small spots. Over that, I'll be shooting a coat of epoxy sealer. Is there a problem with the epoxy sealer having a coat of high build between it and the bare steel? If that IS a problem then I'm understanding I should shoot SPI epoxy directly on the bare steel spots before applying another coat of high build, block it and then shoot the epoxy seal coat. The total combined bare steel I have on the entire car is less than two square inches. Am I just over thinking this?
 
#18
Joe, don't worry about dragging a post out, forums are for learning & many others not yet knowing what all the hell they are doing will read the newer posts & benefit. Sanding through is an all too common thing that has to be dealt with & has been posted about in various threads throughout the years, but would take a while to find.
Yes, this is no longer a rattle can post, not everyone reads everything in a thread completely. many threads change direction from title.
Much info here is posted as best way possible for high end restoration, good & better , not 100% best & what can get by with get done every day.

While having epoxy touching every spec of steel is best, particularly in rust prone areas, some getting away with small slivers is common even among really good painters for various reasons. Touch up of epoxy in said areas is best & epoxy between other product coats with proper time windows is just fine. Light touch up on even tiny spots is my preference, large spots are my firm rule. I've had numerous tiny sand throughs I've gotten away with YEARS later, no evidence. Gotten away with is the term here.
Pull up the pdf file on evercoat g-2 featherfill. They recommend epoxy on bare steel, but back off saying less than quarter size sand through is acceptable.
So, your choice here. You're already going beyond what the average Joe is doing , don't stress too much.

If your sand throughs have been exposed for more than a few hours, give em a light sandpaper swipe before any respraying. Clean steel or aluminum is more important ahead of absolute best coating procedure. I'd consider that a rule.

Joe in Fl.:cool:
 
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#19
I'm just not making myself clear. I've given up on the idea of using anything in a rattle can. I will only be shooting SPI epoxy. If I go ahead right now and shoot another coat of high build I'll be shooting that over bare steel in a couple of very small spots. Over that, I'll be shooting a coat of epoxy sealer. Is there a problem with the epoxy sealer having a coat of high build between it and the bare steel? If that IS a problem then I'm understanding I should shoot SPI epoxy directly on the bare steel spots before applying another coat of high build, block it and then shoot the epoxy seal coat. The total combined bare steel I have on the entire car is less than two square inches. Am I just over thinking this?
I would definitely shoot epoxy over the bare metal spots before high build. Even a reduced coat with sufficient flash time is better than urethane over metal. Urethane is sprayed over bare metal spots everyday, but the failure spots later on will always be where the urethane is over bare metal. It will show as tiny bubbles, then when stripped will be tiny rust spots on the metal. Seen it a hundred times. May take a year, or 10 years, but it will fail eventually.
 
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