First time spraying SPI epoxy; what did I do wrong?

S

steferg

Hi guys,

First I would like to say thanks for all the information on this forum, it is very helpful.
As stated in the title, I sprayed the bottom of my 69 Mustang today with grey SPI epoxy.
In general it came out great, however I did have a few general questions and one specific area that had a problem.

I am using a devilbiss finishline 4 with a 1.5 tip @ 35 PSI.

The paint went down fine, however it is not "smooth". Does that mean I was moving too fast?
Hopefully you can see in the pictures. I didn't get any runs at all. However there is one area where I obviously did something wrong as it looks like a really bad orange peel or something I don't know. There is a picture of that are attached.

I also noticed that where I trimmed around some sections (like the seatbelt reinforcement in the picture) that the paint is glossy and smooth.
That is what led me to believe that I am moving too fast or not laying down enough paint for it to smooth out. Thoughts?

Regardless I am a happy with the outcome, but I would like to avoid/correct my mistakes in the future if possible.

Thanks,
Steve
 

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One picture shows some dry spray, the other is cratering. The dry spray may be from moving too fast, holding the gun too far away, or not enough turns out on the fluid. The cratering appears to be on a small raised surface where you got a little too close and sprayed the epoxy too heavy. The cratering is bound to happen here and there, but it is important to apply wet coats.
 
Cratering is really hard to not happen. Like said there is a fine line between the correct wet and too wet when cratering happens. I have found if you shoot the first coat a bit dry it is less likely to crater if you try for a wet coat on the second.
 
the dry seems to be adjacent to a good wet area. Be sure to clean out your gun between coats lest the drying film inside the gun change your tip size (constricts) If you are using a PPS style cup or the factory Devilbiss with the strainer at the bottom, remove strainer for a higher build paint such as epoxy as the strainer will restrict flow with high build paints and cause the dry spray.
 
Hi guys,

First I would like to say thanks for all the information on this forum, it is very helpful.
As stated in the title, I sprayed the bottom of my 69 Mustang today with grey SPI epoxy.
In general it came out great, however I did have a few general questions and one specific area that had a problem.

I am using a devilbiss finishline 4 with a 1.5 tip @ 35 PSI.

The paint went down fine, however it is not "smooth". Does that mean I was moving too fast?
Hopefully you can see in the pictures. I didn't get any runs at all. However there is one area where I obviously did something wrong as it looks like a really bad orange peel or something I don't know. There is a picture of that are attached.

I also noticed that where I trimmed around some sections (like the seatbelt reinforcement in the picture) that the paint is glossy and smooth.
That is what led me to believe that I am moving too fast or not laying down enough paint for it to smooth out. Thoughts?

Regardless I am a happy with the outcome, but I would like to avoid/correct my mistakes in the future if possible.

Thanks,
Steve
Agree with other posters I had a lot of issues with epoxy when I first started , haven’t had anymore issues in years now , turn your air up at the wall as high as you can , mine is 125psi then set your gun to a minimum 29 psi or so at the regular, dry spray is too far away from panel , too much air , moving too fast or not enough fluid . The cratering is just putting it on a little too thick in that area or possibly some kind of contaminate , likely to heavy tho . I spray my first coat on Medium then second and third coats medium wet , also watch your flash times to let all the solvents escape , if not they get trapped and rise to the surface and cause craters . The great thing is Spi sands like butter so no biggie if you get some flaws and usually you are going to fill over it or sand it anyway so it really doesn’t matter .
 
Thanks for the feedback everyone.
So if a large part of the job shows dry spray, should I try to spray another coat (adjusting my gun/speed, etc) to try to get it right? I'm trying to determine 'how bad' it is to have dry spray like in the photo.
I have more paint, I could go do it now or tomorrow, etc. For example if you guys say it really needs to be a wet coat or it won't do the job (protecting the metal) then I for sure will go respray within the recoat window.

I haven't decided if I am going to top coat this with either black epoxy or the single stage hot rod black or just leave it grey. I have all 3 paints I am just undecided. I think it might be nice to work under the car if it were a lighter color like grey. But if I have this dry spray, now that I know it's wrong it'll bug me forever. So either way I think I'll be doing something... lol

Thanks,
Steve
 
I was that way too :) When doing my Coronet once I got the top painted and reassembled I kicked myself for spending so much time making the bottom "perfect"... A light color is much nicer to work on for sure, lots of light bouncing around. I would just use the black epoxy if you go that way. I used it on all the splash panels and k-frame on the Coronet (and now the Duster) and they are holding up great.
 
Just to make you feel better I just sprayed the hood of my daughters Duster and I got craters where I got too close and slowed down because I was standing on my hose...:rolleyes:
 
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