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Emerald urethane and proclassic acrylic alkyd micro bubbles

7740 Views 18 Replies 10 Participants Last post by  ilararodriguez
Is any one here having a problem with either product bubbling after spraying on new trim? One of the last houses I did, all new flat stock emerald micro bubbled on all of the window extention jambs but not trim. Next house I did it bubbled on all flat stock trim but not extention jambs... another job I did with emerald new flat stock did not bubble at all. Same with peoclassic, one new house I did was just fine, next house bubbled every where... both have bubbled and not bubbled in dif Temps and with and without prepriming trim yet no one seems to have an answer and I cannot for the life of me figure it out. Any thoughts? Spraying with 395 Graco fflp 3:10 tip.
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I had this with a worn out tip. Try a new tip and see if it still happens.
I had this with a worn out tip. Try a new tip and see if it still happens.
Will do, the tip was worn out on the last job. But what really confuses me is why is it bubbling on certain surfaces and not others.
Most likely due to the primer that was used. My bet is the factory primer is something the urethane does not like.
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Most likely due to the primer that was used. My bet is the factory primer is something the urethane does not like.
How would you deal with this issue? Prime trim (which primer?)and let cure or switch brands for high end trim? (Which trim paint?) I have access to sw and bm.
How would you deal with this issue? Prime trim (which primer?)and let cure or switch brands for high end trim? (Which trim paint?) I have access to sw and bm.
1WB.200 + cabinetcoat. like buttah
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Were They Micro bubbles, or fisheyes? Or seeding? Paint didn't freeze did it? Those Hybrid paints are finnicky. Proper humidity and cleanliness are very important.
Sandpapers with a stearate coating may create that issue... worth checking.
1WB.200 + cabinetcoat. like buttah
I do love wb.20
Were They Micro bubbles, or fisheyes? Or seeding? Paint didn't freeze did it? Those Hybrid paints are finnicky. Proper humidity and cleanliness are very important.
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Were They Micro bubbles, or fisheyes? Or seeding? Paint didn't freeze did it? Those Hybrid paints are finnicky. Proper humidity and cleanliness are very important.
Tiny bubbles, happens almost immediately, some lay out, most dont.
I had a whole thread on this last year. It happened to me when spraying BMs Hybryd Advance. My conclusion was a combination of things.
Mostly the humidity was very low that week. In the 20s 30s. And warm, causing the product to dry too quickly..
Also, when loading your machine, try not to shoot the paint back into your feeder bucket. I find that drives air bubbles into the paint. As well if the paint was recently shaken prior to use.
I ended up getting a humidifier and thermometer/humidity reader in my shop.
This fixed the problem. As I used the same can of paint 6 months later and had no issues..
Obviously conditions are hard to control on a new construction setting. In that case, you may consider switching products.
I’ve often wondered if micro bubbles (not micro foaming) weren’t caused by a reaction between the acids in wood and high pH acrylic urethanes creating gases such carbon dioxide similar to the CO2 produced by isocyanates reacting with wood moisture used in 2 pack urethane systems which can sometimes result in micro bubbles. I’ve only experienced micro bubbles with higher pH waterborne coatings. The best way to describe it is when mixing baking soda with vinegar and the mixture starts bubbling releasing carbon dioxide gas. The theory does seem plausible.
cause its **** paint. It wont work over factory primed trim. actually it didnt work well for me even over premium wood primer from SW. Possibly due to lower temps inside when i was doing the job but ill never use that **** again.
In general, I suspect that many urethane modified alkyd emulsion coatings similar to Emerald are prone to micro bubbling, at least based on my limited experiences, having only experimented with two brands on clients’ homes in their earlier development before being available on a retail level, having ditched UMA hybrids after only two uses due to micro bubbles.

The micro bubbling experienced also wasn’t caused by environment, applicator error, substrate, or previous coatings and/or primers. One of the product’s manufacturers even had an a entire web page dedicated to mitigating micro bubbles associated with the one particular product.
I had a similar issue spraying cabinet doors. We were using cabinet coat and the S-W rep wanted to demo me some of the Emerald Urethane. It micro bubbled all over the cabinet doors we sprayed, but not on the cabinet boxes which we brushed. It was during the summer and I believe it was hot and humid out, but don't remember specifically the conditions. It was odd, too, because sprayed on the cabinet doors, it micro bubbled, but not on a piece of new preprimed trim or a door I had kicking around the shop that we sprayed trying to figure it out. The first primer coat was Stix. We thought it might be reacting with that, so they gave me the premium wall & wood, and then shellac. It reacted the same way with all three. Lost my shirt on that one. We ended up stripping the doors one final time and using Cabinet Coat and they came out great. Needless to say, I have never used the Emerald Urethane since.
Cabinet coat and emerald are similar products, aren't they? I wonder why emerald is giving people problems but cc isn't.
Cabinet coat and emerald are similar products, aren't they? I wonder why emerald is giving people problems but cc isn't.
Although I’m not too familiar with and haven’t used CC I “think” it’s a urethane-acrylic dispersion and not a UMA hybrid, the urethane-acrylics not being as prone to micro-bubbling as UMA hybrids seem to be..although I’m making a somewhat broad generalization..
Although I’m not too familiar with and haven’t used CC I “think” it’s a urethane-acrylic dispersion and not a UMA hybrid, the urethane-acrylics not being as prone to micro-bubbling as UMA hybrids seem to be..although I’m making a somewhat broad generalization..
Thats correct. CC is Not a hybrid. Its just an Acrylic Urethane.
I've had thus issue recently. I found that the heavier the coat the more prone it is to micro bubble. Light coats seem to fix this. And if it does micro bubble when you do light coats, it will clear up once its dry. The heavier coats of paint don't alow for the bubbles to clear up well. I wonder if it's also a result of the "self leveling technology" emerald claims to have.
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