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5 Star 2K high build primer

#1
Hello, new here and first post. I have two front fenders I am working on. I replaced the lower fender cups on both, butt welded, planished each weld dot, then ground the welds down. I have applied 2 coats of SPI epoxy primer to the cups, let cure for 5 days, then I have sprayed 5 Star 2K high build urethane primer on top of the epoxy. I have metal finished the cups as close as I could to not have to use filler. One fender will be fine and will be able to block with the use of high build. The other fender will need filler or a couple more rounds of high build. My question is this, can I use the high build primer as the max that will be needed is an 1/8" or less, or should I limit the use of the high build primer, and opt for a filler over the high build? I will seal it once done with reduced SPI epoxy. I know I should have moved the metal a little more at this point, but am past the point of doing so. If a filler can be used over the urethane high build, what does anybody suggest? Thanks!
 
#3
An 1/8" of primer is too much,IMO. I would block most of the primer off in that area, 1coat of epoxy, then filler the next day.
Thanks! I feel I have done this process backwards for sure. I will block the highbuild with 80 grit and reprime with SPI epoxy. What is a good filler to use once I’m back to just SPI epoxy? I will grab a few pictures as well, 1/8” is probably not accurate, it’s less, but just by the feel of my hand it is noticeable for sure.
 

texasking

Active Member
#6
There is probably no one on here that hasn't primed something before it was ready. There is nothing wrong with trying to metal finish something, it's what you should try for, but a small percentage of people can weld in a patch and use no filler. Nothing wrong with a coat of quality filler over epoxy. Much better than excessive primer, IMO.
 
#7
There is probably no one on here that hasn't primed something before it was ready. There is nothing wrong with trying to metal finish something, it's what you should try for, but a small percentage of people can weld in a patch and use no filler. Nothing wrong with a coat of quality filler over epoxy. Much better than excessive primer, IMO.
Thank you for the help on this. I will be ordering some of the rage ultra. Great forum so far, compared to any of the other autobody sites.
 
#8
I received my Rage Ultra and am getting ready to use it, I have blocked the 5K star off, and also used my DA to get the rest of it. I do have a question regarding the SPI Epoxy. I have sanded through to bare metal in several spots and will recover with a good coat of SPI 1:1 Epoxy. Once I block the Rage Ultra off, and if I go down to bare metal in certain spots is it highly suggested to put another coat of 1:1 epoxy, or can I do a coat of reduced epoxy(Sealer) over the bare metal?
 
#11
I was able to get my epoxy primer layed down this AM, however having a few gun issues. I am unsure which direction to go with my gun? More fluid or more air? I am using a graco finex 1.4 tip. My epoxy was mixed 1:1. I am getting what looks like fish eyes. My gun setup was 90% fan open, and fluid control knob turned all the way in, then 2 3/4 turns back out. I sprayed 6” away from the panel. My pressure was set at 30 psi at my wall regulator and using a 25 foot air hose. I have never had water issues in my lines and made sure all my water traps were free of water before spraying. I also wiped the panels down last night with duplicolor wax and grease remover to make sure ample time to flash off. Below are the issues I’m seeing.

4557753E-06F1-47F6-BE17-CE12888523A9.jpeg
 
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#14
I used some duplicolor w&g remover once and it seemed to never dry, leaving a film that would not evaporate. Worst I've ever used. You should be able to put a nice even wet coat with that gun without getting craters.
 
#18
I used some duplicolor w&g remover once and it seemed to never dry, leaving a film that would not evaporate. Worst I've ever used. You should be able to put a nice even wet coat with that gun without getting craters.
I will be ordering reducer and will grab some waterborne as well. I didn’t think about it, but it could be duplicolor hanging around as well?
 
#20
Turn your fluid needle in, 2 turns out max. Open your fan all the way, Overlap each pass 50%. No need for a tack coat. Move faster than you think you should.
I am going to try and move faster, I was going by the fluid control setting I have seen on here for gun adjustments, but will try travel speed first and then try to turn my fluid adjustment in as a second step.
 
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