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-   -   omni epoxy coat problems? (http://www.hotrodders.com/forum/omni-epoxy-coat-problems-216775.html)

inkfreak1976 03-15-2012 08:41 PM

omni epoxy coat problems?
 
i sprayed omni epoxy coat as a sealer on advise of my jobber paint supply, I think it was the gun that i was useing god i hope so cause after i was done it went in the trash. seeing that i had no problems with my finish line guns doing the same thing nice even wet coats no tiger striping.
it mixed 1;1;10% 1 part epoxy, 1 part hardner, and a little over 10% urithane reducer.
problem is when the compressor was at full pressure it sprayed great inlet pressure at about 45-50 lbs with a 1.4 tip, trigger turned all the way in then backed out 4-5 turns test spray and fan was perfect, after i started spraying it started to come out a little dry like 30 sec after i was spraying. to compensate i put in a splash more reducerr mixed and cleaned gun and reset gun = perfect spray.
30 sec after starting again same thing. i did wait the 15 min induction period. so figureing that that was the best i was gonna get i sprayed 3 very slow moveing oats trying to get it as wet as possible.
i let it dry and plan on spraying base clear tommarow, about 3 hours later after spraying i checked out my work and litely tested the finish. there was a powder like resadue comeing off on to my hand.
my question is what do i do now do i just clean with wax and grease remover and spray base clear, or do i scuff then clean. then paint any help would be great ive just never seen this before.

MikeyBob 03-15-2012 10:17 PM

Me either...

Usually when it starts spraying spotty or dry for me is when the omni epoxy is getting cold and thick....
My guess about the powder is something isn't right in the catalyst, you might want to check if theres any sediment or anything at the bottom there. That or the reducer you used had a bad reaction, I believe the tech sheet for Omni says to use acetone, so it could be that too.


Personally, I'd scuff it, clean it and spray my base - but that might not be a acceptable risk if you're painting an entire car. I wouldn't sweat it though if it's something smallish.

inkfreak1976 03-15-2012 10:37 PM

Quote:

Originally Posted by MikeyBob
Me either...

Usually when it starts spraying spotty or dry for me is when the omni epoxy is getting cold and thick....
My guess about the powder is something isn't right in the catalyst, you might want to check if theres any sediment or anything at the bottom there. That or the reducer you used had a bad reaction, I believe the tech sheet for Omni says to use acetone, so it could be that too.


Personally, I'd scuff it, clean it and spray my base - but that might not be a acceptable risk if you're painting an entire car. I wouldn't sweat it though if it's something smallish.

yeah unfortunatly its a whole car, ill see what otherss say . my jobber said to use the reducer for the thinning. he said that its done all the time. ive been doing some reasearch and have seen many many close resemblances to this and there saying the same thing temp and catalyst, but the cat. was a new can never opened the epoxy was warm in fact 73 deg. and surface temp was at 75 so im thinking that it was the gun. i had never used it before. im thinking that it just wasent thin enough, ive read to thin it almost 50 % to spray out of a 1.3 tip so im thinking that it was just a bit thick still and the additional air psi from starting to spray just had the push to force it threw. thanks for your in put and see what others say, and i think ill call my jobber also see what they have to say.

swvalcon 03-16-2012 09:50 AM

The first thing I check if my gun starts to do that is to check the air vent on top of the cup lid. Second is the gun tip to see that its not plugged.Just sand the car down and paint or reseal frist if you want.

67Elcamino 03-16-2012 01:22 PM

Quote:

Originally Posted by swvalcon
The first thing I check if my gun starts to do that is to check the air vent on top of the cup lid. Second is the gun tip to see that its not plugged.Just sand the car down and paint or reseal frist if you want.

This might sound stupid , but did you strain the paint before pouring into gun? Also are you sure its a 1:1 mix Ive used a few different Epoxies and always noticed they are a 2:1 ratio.

HVAC Phil 03-16-2012 02:06 PM

You sure the ratio is 1:1? Last time i used Omni epoxy, it was 2:1 epoxy/catalyst.

JohnnyK81 03-16-2012 02:47 PM

Omni IS 2:1.. There's your problem.

inkfreak1976 03-16-2012 06:12 PM

ok you guys are right it is 2;1 i posted it wrong, i checked my paint mixing cup and i did mix it orrectly because i always mark with a sharpie marker. i called my jobber and they had the ppg tech contact me, well they tryed to blame everything on me of coarse because im not a body shop, and basicly the jobber told me the the wrong percentage of reducer. its from 10- 50 percent depending on tip size. with running a 1.4 tip it should of been a 50% ruducer. basicly what i had to do is wet sand with 600 they recomend a 2nd coat of epoxy but i still have my doubts of the product. so after the wet sanding i washed and rinsed well dryed , now im leaveing it to cure for another day. and off to base and clear. but i do think that its pretty bad to have a company try and save face more than takeing the blame for in accurate tech sheets. and i also had a good freind thats been in the auto body feild for 20 years say that it coulda been the catalist but theres no real way to say. so i hope that this might help some one in the future with this same problem. thanks for the replies and the help

mitmaks 03-16-2012 11:53 PM

Possibly had too much air and you pretty much blasted it on. I'm not sure how long you've been spraying but every product that I spray is a little bit different and I have to make adjustments. I've been painting for many years too and do it on daily basis.
When spraying something as big as a car or even just a single body panel make necessary adjustments to the gun and to a spray out on the piece of cardboard/scrap, don't just go shooting car and make adjustments on the car.

inkfreak1976 03-17-2012 01:02 AM

Quote:

Originally Posted by mitmaks
Possibly had too much air and you pretty much blasted it on. I'm not sure how long you've been spraying but every product that I spray is a little bit different and I have to make adjustments. I've been painting for many years too and do it on daily basis.
When spraying something as big as a car or even just a single body panel make necessary adjustments to the gun and to a spray out on the piece of cardboard/scrap, don't just go shooting car and make adjustments on the car.

i shot on a tester paper that i had taped to the wall, pretty much everytime i started to have problems, i would make the adjustments if necassary. but that got to be every 20 sec. and i knew that if i didnt get going on it i was going to lose my wet on wet, so i did the first coat the best i could. basicly adjusting my speed to get as wet of a coat as possible. i decided to do a second coat because it came out tiger striped as all hell and i knew i couldnt leave it like that so i knocked down my pressure 20 lbs did a test and it sprayed like a dream on the test paper. so i thought that i was good, and im not talking a couple trigger pulls i lined a good part of my wall with 18 inch paper and it shot awesome perfect fan perfect material application. and did several passes. oh and at that time i also splashed in some extra reducer and mixed strained, and cleaned gun before second coat and test. it was good so i started on the car and the same crap happened not 30 sec later so i did the same thing slowed my speed and tried to get the wettest coat i could, still tiger striped after the second coat and following proper flash times. i decided to do a cross pattern to try and blend the stripes. it filled in the stripes , but did the same thing. so i stopped cleaned up and let it cure over night. the plan was to do base and clear the same day but the way it sprayed i didn't want to risk the base and clear until i knew what the out come was going to be thanks god for gut instincts.

HVAC Phil 03-17-2012 03:16 AM

Quote:

Originally Posted by inkfreak1976
ok you guys are right it is 2;1 i posted it wrong, i checked my paint mixing cup and i did mix it orrectly because i always mark with a sharpie marker. i called my jobber and they had the ppg tech contact me, well they tryed to blame everything on me of coarse because im not a body shop, and basicly the jobber told me the the wrong percentage of reducer. its from 10- 50 percent depending on tip size. with running a 1.4 tip it should of been a 50% ruducer. basicly what i had to do is wet sand with 600 they recomend a 2nd coat of epoxy but i still have my doubts of the product. so after the wet sanding i washed and rinsed well dryed , now im leaveing it to cure for another day. and off to base and clear. but i do think that its pretty bad to have a company try and save face more than takeing the blame for in accurate tech sheets. and i also had a good freind thats been in the auto body feild for 20 years say that it coulda been the catalist but theres no real way to say. so i hope that this might help some one in the future with this same problem. thanks for the replies and the help

Omni epoxy requires another coat if out of a 3 day window, so if 3 days have passed, you MUST apply another coat. Stuff sands lovely doesn't it? Nice and gummy on the sandpaper. Use SPI epoxy next time, you will see the OMNI sucks in comparison.

mitmaks 03-17-2012 02:24 PM

is the base coat metallic or solid color? If its solid color I'd wetsand car with 600 and then just go with base.

inkfreak1976 03-17-2012 09:20 PM

when i talked to the ppg tech he stated that even after a 72 hr period that it would have to be reapplied or scuffed/ sanded. since it was right on the edge of 72 hrs since the last coat today, yesterday i wet sanded with 600 grit it came out really nice and was easy to do, today i cleaned and prepped the car for base and clear.
its a light baby blue no metallic , the name of the color is grabber blue, i layed down two heavy coats of base waiting 5 mins in between coats as per the tech sheet that im noticing aren't very reliable, waited 20 mins shoot to heavy wet coats of high solid clear with med hardener, the temp was close to 80 so it flashed a little faster than what i wanted. Te clear came out with a little orange peal but its getting wet sanded and taped for stripes so the peel will come out. after the stripe is painted another 4 coats will be applied and this time im going to reduce it as per recommendation of a good Friend of mine that has 20 plus years of body work experience. he couldn't believe that they didn't put that as a option on the tech sheet. after that it will be wet sanded down to 4000p the buffed and sanded, i case you might be thinking wow that's a lot of clear.

Donnie Smith 03-18-2012 07:45 AM

Quote:

Originally Posted by inkfreak1976
i sprayed omni epoxy coat as a sealer on advise of my jobber paint supply, I think it was the gun that i was useing god i hope so cause after i was done it went in the trash. seeing that i had no problems with my finish line guns doing the same thing nice even wet coats no tiger striping.
it mixed 1;1;10% 1 part epoxy, 1 part hardner, and a little over 10% urithane reducer.
problem is when the compressor was at full pressure it sprayed great inlet pressure at about 45-50 lbs with a 1.4 tip, trigger turned all the way in then backed out 4-5 turns test spray and fan was perfect, after i started spraying it started to come out a little dry like 30 sec after i was spraying. to compensate i put in a splash more reducerr mixed and cleaned gun and reset gun = perfect spray.
30 sec after starting again same thing. i did wait the 15 min induction period. so figureing that that was the best i was gonna get i sprayed 3 very slow moveing oats trying to get it as wet as possible.
i let it dry and plan on spraying base clear tommarow, about 3 hours later after spraying i checked out my work and litely tested the finish. there was a powder like resadue comeing off on to my hand.
my question is what do i do now do i just clean with wax and grease remover and spray base clear, or do i scuff then clean. then paint any help would be great ive just never seen this before.

Many epoxy primers have an induction time. This is the time the two products need to set while the chemicals (epoxy and catalyst) needs to set in order to mix properly. Omni and Shopline are the same product labeled different. I think platinum PPG distributors sell Shopline and if they are not a platinum they sell Omni. That is what I have been told anyway. However, I would allow the Omni epoxy set for 15 to 20 minutes before using.

The mixing ratio is 2:1 (2 parts epoxy 1 part catalyst) I have added up to 10% acetone when using it as a sealer to help the epoxy flow out better.

1. Once mixed, allow it to set 15 - 20 minutes. (induction time)
2. Apply a medium wet coat (1 coat should work as a sealer, but you can apply up to 2 coats. If you do, allow 15 to 20 minutes between coats.)
3. Allow the epoxy to dry at least 30 minutes, but no longer than 72 hours (3 days) before applying base coat. If you wait longer than 72 hours, the surface must be lightly scuffed before applying base coat.

I would not apply more than 2 coats. Applying too much may not allow the solvents to escape properly, which could lead to problems.

If using as a sealer, I would use a 1.4 spray gun using around 20 to 25 psi at the gun. This may vary depending on the gun you are using. If it is not a HVLP, it is going to require more 45 to 50 psi at the gun.

Here are two videos about mixing and spraying epoxy primer. It is not being used as a sealer in this video, but goes through the mixing steps.

I hope this helps and good luck with your project.

Mixing Epoxy


Spraying Epoxy


If you are looking for additional auto body and paint training, then check out what I have available for you. http://***************/AutoBodyGuides

inkfreak1976 03-18-2012 11:55 AM

Quote:

Originally Posted by Donnie Smith
Many epoxy primers have an induction time. This is the time the two products need to set while the chemicals (epoxy and catalyst) needs to set in order to mix properly. Omni and Shopline are the same product labeled different. I think platinum PPG distributors sell Shopline and if they are not a platinum they sell Omni. That is what I have been told anyway. However, I would allow the Omni epoxy set for 15 to 20 minutes before using.

The mixing ratio is 2:1 (2 parts epoxy 1 part catalyst) I have added up to 10% acetone when using it as a sealer to help the epoxy flow out better.

1. Once mixed, allow it to set 15 - 20 minutes. (induction time)
2. Apply a medium wet coat (1 coat should work as a sealer, but you can apply up to 2 coats. If you do, allow 15 to 20 minutes between coats.)
3. Allow the epoxy to dry at least 30 minutes, but no longer than 72 hours (3 days) before applying base coat. If you wait longer than 72 hours, the surface must be lightly scuffed before applying base coat.

I would not apply more than 2 coats. Applying too much may not allow the solvents to escape properly, which could lead to problems.

If using as a sealer, I would use a 1.4 spray gun using around 20 to 25 psi at the gun. This may vary depending on the gun you are using. If it is not a HVLP, it is going to require more 45 to 50 psi at the gun.

Here are two videos about mixing and spraying epoxy primer. It is not being used as a sealer in this video, but goes through the mixing steps.

I hope this helps and good luck with your project.

Mixing Epoxy


Spraying Epoxy


If you are looking for additional auto body and paint training, then check out what I have available for you. http://www.CollisionBlast.com/AutoBodyGuides

hello donny i did everything that the tech sheet required, waited the induction time, and mixed it correctly. i had spoken to a tech at the manufacterer at ppg, the tech said that the tech sheet should have been changed for the amount of reducer, to spray it as a sealer. he recomended up to 50 % reducer, depending on what gun and the way the individual sprays.
i also was useing a gun that i was not used to spraying with, because i didnt want to run epoxy threw my base clear gun, and my primer gun only has a 1.8 tip so i got a cheep gun with a 1.4 to do rhis with.
i sprayed base and clear yesterday and base came out really nice and the clear came out i bit orange pealed. but there was no reducer added to the clear. wich seemed odd to me because every other clear coat that i ever sprayed had reducer added to it. the tech sheets on omni products are highly in accurate and do not give the proper info to make the product useable to everyone. ive sprayed many paints and dont remember any line of products being this diffacult to work with.


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