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I painted an airplane for a guy many years ago, about 20 gals Imron. Moved it over to a hangar where a guy was going to do some STC updates. Freshly painted, I come in and the guy has a strip of duct tape on the wing (he's certified a&e) about 14 in long with a goofy look on his face and says "have you done the duct tape test yet"? Of course I'm way pissed and after some heated discussion I said if you F that up you will be fixing it! I turn my back and he pulls the tape off, came off clean no trouble. If he had been 20 yrs younger I would have punched his lights out right then!
Sorry ...your post brought back memories. :oops:
Ok guys it was a long 7 days but I finally have a beautiful base down.... What a week.... I found a secret, I cranked up the air pressure to try to flash off more of the reducer before it hit the panel. It worked MUCH better. Don't ask what the number was cause I don't know my gauge is not working such that I trust it.

Don't mind the grasshopper on the door he jumped off after the photoshoot.

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So now I am scared to death to put the stripes on and then the clear over them. This was such a cluster if I need to fix something again having the decal under there will make it painful to fix.....

What is your opinion decals under of on top of the clear? The hood is getting a mask and a black strip in the morning before the clear.
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Active Member
Under clear, blocked leveled and buffed looks more Barrett Jackson show car to me, but very nice. On top of the clear seems more old school and maybe authentic. Congrats on getting the base down!
So one more piece of information. Before all this started Barry said I could use the Motobase Reducer for his base since I forgot to order SPI reducer. Guess what the Motobase Reduce and SPI black base did the SAME THING.... There has to be something wrong with the Motobase Reducer I got from Chads...
Did your daughter stop helping when you about lost your mind?
She's going to have an awesome car!
Honestly I am glad she was otherwise busy this weekend. She sandblasted some of the radiator support sheet metal that needed to be painted blue which was a huge help to me to finish up everything that needs to be B1 blue but she would have learned some new words this weekend if she was around.
Man, this thing is fighting you all the way. Persevere bro! Looks awesome. That's some tedious masking.
It is a factory '71/'72 scheme that you can buy a masking kit with everything laid out for you :). It was not as hard as you may think just took some tricks to get it down without wrinkles and bleed under.
Ok final word from Chad. He has seen this problem before with SPI Epoxy and Motobase. He has strict time limits that work for him in his shop for time between SPI products and Motobase as the solvents are not compatible. You can not rush the base on the epoxy so don't completly follow the Perfect Paint Job times when using Motobase on SPI epoxy, let it set until it is completely dry. 3 coats he gives it 3 weeks. A simple sealer coat can be overnight.
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From Chad.

Jim Kueneman a few times, the base has absorbed the solvents from the epoxy, epoxy solvents and urethane solvents are NOT compatible. therefore when you re-apply base over base that soaked up epoxy solvents it is now acting as if it is attacking itself. But in reality it's just working against the original epoxy solvents. Now that they are trapped in the base I am unsure how long of a cure time it would require to remedy the issue. I would put down the tools, put the car outside and walk away for a week. Time is the answer.
I wanted to jump in here to try to clarify something as it seems there was a little miss-understanding. This is not a motobase/spi epoxy issue. I have seen many things applied to fast over SPI epoxy, pro-spray base, moto-base, ppg base, omni base, and even SPI 2k primer. All will produce similar problems. the issue has nothing to do with what product is chosen to put over epoxy, if solvents have not escaped from the epoxy you can't top coat it.

From what I understand 3 coats of SPI epoxy sealer were used on this car. Below this is a copy from the SPI website itself. NOTE: it says to spray ONE wet coat of epoxy as a sealer. NOT 3 coats.

"When all of the primer blocking and any necessary primer repairs are finished it’s always best to use the epoxy as a sealer. Mix up enough epoxy to go around the car with one wet coat and adding a double shot glass of SPI 885 Urethane Reducer per quart. Let the epoxy sit for 30 minutes. Stir one more time and strain. Spray one full wet coat of epoxy over the entire car. The epoxy should sit for 6 hours before spraying basecoat or the next option is let it sit over night and wet sand the epoxy with 400-800 then spray the base. "
Also: I do not know the mix ratio chosen for use as a sealer for SPI in this scenario, many people use different ratios. which is fine, but the less reducer you use the longer it takes to cure. When I use it as a sealer, which almost ever job we do. I spray it 1:1:1, I apply only ONE coat, I treat it as a adhesion promoter, I am not trying to get full coverage, I don't need it with Motobase, it covers like ink. IF a true white undertone was required, spray one coat of white motobase down first over the ONE coat of sealer, not 3 coats of sealer. There is a big difference here. The adhesion weak link is always the base coat, therefore applying one thin coat of epoxy as a adhesion promoter makes me feel much safer against anything that may go wrong. I also mix it 1:1:1 because I know solvents escape much faster. this makes me feel safer against non compatibility issues as we have seen here.

Also when I stated when I do 3 coats of epoxy I let it sit for 3 weeks. yes, I do that however in that scenario it is not mixed as a sealer and it is sprayed with a larger tip than maybe even I should be using, however I wait 2-4 hours between coats, and we have found in the second week it may still leave residue on the sand paper and find it sands better after 3 weeks. BUT that is mixed 1:1 as a primer. Also a completely different scenario.
I hope that puts some clarification to this but at the end of the day you CAN'T rush top coating epoxy. If only one coat of epoxy was used we would most likely not have any issues with this paint job.

I also think as Barry posted earlier on this thread, time is on your side.

That is the writing on the wall we should all listen to, if we push products to their limits we are bound to get bit sooner or later.