I have recently switched over to HVLP/ gravity
feed spray guns. What tip size is best for clear coats,base,
and/or primers. If I thin all my paint to the same viscosity
do I stay with the same tip? I currently have 1.3mm,
1.7mm, 2.0mm and even a 2.2mm.
What differences should I expect from these?
Also I find my primer settling out to quickly between coats
in the gravity gun, do you guys have that problem? I
think I'll go back to siphon feed for primer.

well i guess if i had to choose i would use the 1.3 for clear and base and the 1.7 for thicker primers and the 2.2 for polyester primers. but, i do use a 1.4 for base but a 1.3 should be ok.

you could almost spary texture coating outa that 2.2 tip!! maybe gelcoat...

Hey
How bout when you're spraying metallics? Do they need a bigger tip? Do you need anything for Pearlescents? Have a good one! Great post!
Thanks
Troy

I use the 1.4 tip on a Sata gun for everything except undercoating of course. I've found that staying with just one tip for primer,paint and clear keeps me at the top of my paint game.

The trick is to thin/reduce your material to your own style. Useing one gun/tip is like useing one tennis racket or one bowling ball. It's tough enough to dial in a feel without multiple surprises. . .
Where did I leave that link? hold on a sec


Hope to help . .
check it, http://www.a2zautoforums.com/showthread.php?t=2795

I have and use a 2.2. I use it to spray KoolSeal roof coating on my motorhome roof.
If life only gave me one tip, it would be a 1.4. That's about as close to universal as you can get. A larger tip (1.6, 1.8) wold be second for primer. From there, your own experience and needs should be your guide.

This may be a dumb question but here goes.
Is using a larger tip and backing off the fluid adjustment
different than a smaller tip? This is what I want to know
what differences there are. Honestly I can't tell a difference
between a 1.4 and a 1.7

The size of the tip affects 2 major things: the amount that flows through it and the atomization of the paint.
Small tip = low flow and fine atomization
Big tip = high flow and less atomization.
Better atomization usually means a smoother, flatter job. The little tiny particles flow out better than bigger chunks. The trade off is the volume part. Really thick paint like filler primers just will not flow through a small hole. You generally pick a tip size that is the best compromise between the two. You can add reducer and use a smaller tip but that is not without a few problems like coverage and runs.
Under the same conditions, your 1.4 should give you a better final finish.

I have tried going to a 1.3 set for clearing but after the first shoot went back to a 1.4 in my HVLP's. It just lay's better for me personally. I use an old Alltrade syphon feed for my primer's with probbly a 2.0 tip. It's so old it's hard to tell but the orfice is fairly big. Having a dedicated primer gun is almost a necesity to prevent possiable contamination into your paint job.A flake/pearl gun is a good idea as well to prevent contamination into a solid color job unless your SURE you got all the previous job out.As for metalics or pearls a 1.4 will shoot most standard OEM type but if your talking large flake (as in gaudy) a larger tip is needed as well as an agitator cup if you can get access to one as the flake will settle and cause you a world of trouble.

are you using an american gun or european gun? because a 1.3 european like a sata is not the same as an 1.3 american. big differnce. My graco gun which personally i think puts the sata to shame (i have 2 satas) has a 1.3 and shoots a much tighter pattern then the sata 1.3.

My first sata gun was a sata 2000 with a 1.4 tip i used it soley for clear then i got a sata digital with a 1.3 and i use that for clear and i couldnt be happier. less orange peel etc. but its also a matter of technique.

I believe the tip sizes are an international standard based on the size of the hole in the tip. Now, what different companies do with the paint once it flows out of said hole is the reason we have so many manufacturers. The taper of the needle enters the picture also.