small bumps in clear

hello!! man this toyota has been whipping my but...mostly my fault .....anyway i had to redo the hood from not enuff coverage clear looked awesome that was friday......sunday sanded with 600 wet...monday evening sprayed 2 coats of base...after base dried i could see some sanding scratches and and lil bit of trash and this morning i wet sanded with some 1500....dried and wiped down with 710....and 15 minutes later prayed another coat of base..(THIS MAY BEEN WHERE I MESSED UP I STARTING SPRAYING BASE BEFORE W&G DRIED? IDK....let base flash for 45 minutes...went 2 rounds speed clear slow activator,no reducer..about ten minutes these little pimples show up..just in one area.. the rest off hood looks good..pulled out in sun for ten minutes and looked like that enhanced the pimples....temp 85 degrees 63% humidity.....tell me where i screwed up and can this be wet sanded out....appreciate all input.
 

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Jim C

Oldtimer
speed clear is very finicky. its a love hate thing for me. i love how fast it is and i can get hte job done quick but i cant stop it from getting very small bubbles in the surface. for what i am doing it though it doesnt matter because its all sanded and buffed afterward and the bubbles are so small that once its buffed they are totally gone. the heavier its sprayed and the higher the airflow the more its prone to bubbles.
 

AAE

Learner
speed clear is very finicky. its a love hate thing for me. i love how fast it is and i can get hte job done quick but i cant stop it from getting very small bubbles in the surface. for what i am doing it though it doesnt matter because its all sanded and buffed afterward and the bubbles are so small that once its buffed they are totally gone. the heavier its sprayed and the higher the airflow the more its prone to bubbles.
Hmm, I only use speed clear. Today, the panel was 108 degrees. Came out really nice. Used slow activator and a 1.3 tip. Single fender.
 
i sprayed 8 panels some twice do to my inabilities so far with the speed clear...in the coolness of early december and now the extreme heat of july... and today was the first time i see the tiny bubbles and only in a 18x24 inch area..the rest of the hood looks good....and Jim C i do seam to spray a little heavy and i also bumped my pressure up 33psi with my devilbis plus to brake it up better because i put no reducer in it this time,,plus im trying to speed my technique up a bit,,because i feel im a bit slow and apply clear too heavy... next time ill drop back on pressure and add reducer..and see if problem goes away. thanks Jim C
 

Jim C

Oldtimer
I have been through around 5 gal of it over the past 4-5 mos. i have sprayed it as 2 coat product and also as a 4 coat product. I found bubbles both ways. Tried all 3 hardeners. The bubbles are much less noticeable than in the picture of the op. Honestly most people would never even see it. These are really tiny and usually show up 10 min after the last coat.
 
yep about ten minutes is when mine appeared and at the right angle they are very noticable,,,Jim C do you use reducer in your mix?? the 3 things i did differant from previous times was no reducer.5 more psi and probably a half turn out on fluid...a strange hazard of the trade indeed...well imma be cuttin and buffin tommorow and see what happens....thanks again and AAE it was a cold 86 today bout 830 am when i sprayed.
 

texasking

Active Member
@JimC, I'm surprised you have had these issues with it. I, too, have sprayed 5-6 gallons and the only time I had a hint of what you are describing was when I had a booth full of motorcycle parts, and it probably took 15-20 minutes to clear them all. I turned the fan off as soon as the overspray cleared. On the first part I cleared, I noticed what looked like very mild solvent pop or dry overspray, but all the rest of the parts looked great. I chalked it up to leaving the fan running while finishing the rest of the parts. I have only used the medium and slow hardener, and never reduce. Maybe you have more airflow than I do, or some other different condition causing it?
 

Jim C

Oldtimer
Well i am not spraying this stuff in a booth. I have zero airflow. This will solvent pop more when there is airflow vs no airflow. I have reduced it and not reduced it. I dont have any conclusion as to what is better...YET. Most of the time i am spraying 4 coats. 2-2coat sessions with 15-30 min between but the bubbles show up after coat 2 as well as coat 4 but there is more after the 4th coat than after 2 which would make sense. You can see the bubbles in the pic.
C02EF63D-9E53-49E1-A91D-5D5C44E20B88.jpeg
 

AAE

Learner
Well i am not spraying this stuff in a booth. I have zero airflow. This will solvent pop more when there is airflow vs no airflow. I have reduced it and not reduced it. I dont have any conclusion as to what is better...YET. Most of the time i am spraying 4 coats. 2-2coat sessions with 15-30 min between but the bubbles show up after coat 2 as well as coat 4 but there is more after the 4th coat than after 2 which would make sense. You can see the bubbles in the pic. View attachment 12110
Have you mentioned this to Barry? You know how much he loves feedback.
 

Jim C

Oldtimer
Yes we talked awhile back mostly about how to go about doing a 4 coat job with the stuff and we left off with doing 2 coats like the tech manual says, wait 30 min then do another 2 coats. I completely understand this is a 2 coat clear and 4 coats is going beyond recommendations so i expect the bubbles in my situation and its completely fine since it all sands and buffs away with no issue BUT i am seeing these even after the first 2 coats as well. Not as bad but they are there. The humidity here is intense, prob 95% or better every day so i am thinking it has to do with that but not 100% sure. I probably wont know until fall when it drops.
 

Barry

Paint Fanatic
Staff member
Sorry, I missed this, but plenty of right answers posted.
Only thing I can add since it was one spot my best guess is that it was an area the had excess clear in that spot before or that spot with the high humidity held the wax and grease remover.
This does not look like pop too me, so im thinking wax and grease remover needed more time with the high humidity.
 

AAE

Learner
Could it be iso clumping? Jim, what gun did you use? I have no answers just asking questions.
 

Jim C

Oldtimer
I am always spraying with a minijet 4400 with a 1.4. I am also spraying at about 22psi instead of 30 so it doesnt get atomized really good. Not spraying in a booth and i have to keep overspray way down so low psi with a narrow fan is my only option. Could very well be that each if my coats is going on heavy because of that and causing it. Dont get me wrong, i do really like the clear. It flows out like glass and my issues are prob from environment and how i have to spray. Just saying the clear is finicky because you dont have that wide margin for error like you do with universal or others. It needs to be done exactly right. If not it lets you know lol.
 
Jim c your bumps looks the same and mine slightly bigger....kinda like fine tree sap.. and im also not in a booth with just some box fans to pull the dust out.and Barry yes that was my first thought it was the w&g because i forgot the dry time. i was half way across the hood with spraying the base when it hit me DANG.and saying i hope that dont come back to bite me...and after the base flashed 45 minutes with nothing obvious looking i proceeded to clear...i guess its possible the base trapped it in...then the clear softened the base for it to escape..? thanks to all for the input
 

AAE

Learner
I am always spraying with a minijet 4400 with a 1.4. I am also spraying at about 22psi instead of 30 so it doesnt get atomized really good. Not spraying in a booth and i have to keep overspray way down so low psi with a narrow fan is my only option. Could very well be that each if my coats is going on heavy because of that and causing it. Dont get me wrong, i do really like the clear. It flows out like glass and my issues are prob from environment and how i have to spray. Just saying the clear is finicky because you dont have that wide margin for error like you do with universal or others. It needs to be done exactly right. If not it lets you know lol.
Someplace in my fading memory bank, I recall Barry telling me that a 1.0 in a mini is like a 1.2 in a full size gun. If so, then you're using about a 1.6.
 

Jim C

Oldtimer
Other way around. The mini 1.4 sprays about the same as a full size gun with a 1.2. All my guns are 1.4 and the mini puts out nowhere near what a full size gun with a 1.4 will.
 

W.A.R.

Member
I may be way off, but I had a similar looking situation years back with single stage black.
Only thing it seemed like it could be was some old opened hardener.
Remember Barry saying something about opened cans of hardener especially ones that are less than half full will pull moisture inside and cause problems like that.
 

Jorge M.

Member
I guess I’ve been very lucky in here with the shops that use it and the weather conditions.

Warmer it’s been is around 80F and some are blending Fast/Med and getting great results for bumpers and 2 panel jobs. Bigger jobs they switch to Medium Act. and so far so good. Painters that really spray it heavy get a hint of die back but then they adjust accordingly and the finish is great again.
 
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