HVLP cup size..


New Member
Got some more newb questions. I feel bad asking a lot of stoopid questions, however that is why I joined, I reckon. When I purchased my first and ONLY spray gun, I did it before finding SPI products and this forum. I have never painted an entire car before so keep that in mind, other that 5 coats of SPI epoxy to date. I bought a FinishLine FLG4 mostly because of the depth of my pocket. My restoration currently sits in epoxy (final coat last night over filler) and awaits for SPI 2K primer that arrived last week. The FLG4 has only a 20oz cup and it seems I am outta paint before I even finish a fender. It's not a 59 caddy in length but my 66 Olds seems very long to the size of my gun's cup. They do make an aluminum 900cc cup for my model but just wondering, considering the FLG4, what options would you take. The size of cup has not mattered with the epoxy but am concerned moving to primer and BC/CC due to their pot lives. If the cup size is ok, can you offer any tips with 2K primer that will ease my concerns.

Thanks in advance,


Most of my cups were 32oz, which would be basically the same as the 900 you are looking at. I thought it was a good size for me and what I was doing, I wouldn't have wanted anything bigger by any means. If you are concerned about it and are having issues then its a wise choice to get the bigger one. You wont have to worry about running out as much, but might suffer a little arm pump, its no joke putting down several coats with a full cup if you aren't used to it.

Tips for 2k primer, spray with a larger tip, at least a 1.8 I think is the minimum on the tech sheet but larger doesn't hurt. Another on the tech sheet I believe is to mix thoroughly, 1 full minute, seems simple but its really important. Make sure its fully flashed before you recoat, 5-10 minutes, you can watch it flash. Dont get in a rush and double coat something if it hasn't flashed. I had a lot better luck with it at 70 degrees or warmer. If you have trouble getting it to spray nice add a little reducer, even reducing 5% can make a nice change if your having trouble.


Active Member
I agree with Sprint about the nozzle size. 1.8mm is minimum per tech sheet, but I picked up a 2.2mm tip for the FLG4 (I used the same gun as you are using from bare metal through clear). I tried the 1.8mm tip and just wasn't happy with how it was going on. The stuff kicks pretty quick, compared to other products, and once it starts to go it almost looks like you are spraying bedliner. If this happens, stop and get the gun cleaned up so it doesn't dry up in there. You can block out the flecks of paint that may happen with no problem.

Just mix as much as you need for one or two coats to help with the pot life. If you've got everything ready to go, you can even mix up more in between coats (again, like Sprint said, 5-10 minutes) since there is not induction time...just mix it really well (I think that Sprint guy is pretty smaht!)

I can't comment on the cup size (I used what it came with) because I painted a Triumph Spitfire, which has about as much metal as probably one of the fenders you're painting o_O

Good luck!


New Member
I agree with Sprint about the nozzle size. 1.8mm is minimum per tech sheet, but I picked up a 2.2mm tip for the FLG4
Thanks for sharing your experience with the FLG4! I'm glad I purchased the 2.2 tip when I originally purchased the gun. I will be looking at buying the bigger cup shortly, but in the meantime back to doing some arm curls to strengthen my spraying arm :)