Im repainting a truck and i stripped it to bare metal and this weekend i shot some primer on it Mar Hyde 2k. Im using a Buffalo professional spray gun on it, tip size is unknown and the primer went on dry and over sprayed really bad. I was mixing it 4:1 first time i tried it using about 50 psi and the over spray was really bad. I changed my mix to 4:1:1 and reduced my pressure several times, finally down to like 20 pounds and i was mixing around 4:1:2 still going on dry and bad over spray, it feels and looks like someone thru a bunch of sand on it. After it set for about 15 minutes i could sand it with no problems...any ideas..oh im measuring the tip nozzle tomorrow to see what size it is.. Thanks

Uhhhh.... Isn't that the $25 siphon feed gun from Home Depot? That thing has like a 2.0 tip and is fine for around the house stuff. Cars???....not so much. You need a decent quality gravity style gun. Siphon feed guns can't pull these heavy 2ks out of the cup well enough for decent results in my opinion. Hope you're not planning on doing your whole job with that thing.

Well i paid 50 bucks for gun 5 years ago and used it to paint color and it worked good. Any way I did prime the whole truck 1 coat so now i have to sand it all back off.So i need a gravity feed gun?.....Another question will the primer thats on there if i get it all smoothed out stay on or will it flake off if painted.

I used to use Mar-Hyde 2K years ago, it was always so thick!
I had to thin it a lot and use a slow reducer.
It also settled real fast in the gun so I used the devilbiss bag system
so I could lay the gun on its side between sprayings
and shake it well before starting again.
If sat upright to long it would build up in the neck on a gravity gun.
Good primer though, it did real well.

I have a 1.8mm nozzle and i also found the vent tube partially blocked . I did some sanding on it with some 180 grit and it sands easy and the 1 coat seems not to be very thick, but it did sand out smooth. If i sand it all down can i recoat it with another primer coat? because some areas are showing metal...i Think i like the Upol 2k primer better that i used 4 years ago it was non sanding and went on great even with a 25 year old spray gun.

If i get a gravity feed gun what size tip should i use?

Depends on the viscosity of your primer,
thinning the way I do, a 1.3 will work fine but I
usually go with a 1.7 when it's not thinned much.

I got a hvlp gun with 1.8 tip and I sprayed the truck with another coat and sanded it down with 320 and here is what it looks like.

Bruce2 wrote:Im repainting a truck and i stripped it to bare metal and this weekend i shot some primer on it Mar Hyde 2k.

I hope you didn't spray that 2k directly over bare metal, that 2k isn't made for that.
It needs an etch or epoxy first.
If not, it may peel off later.

http://multimedia.3m.com/mws/mediawebse ... 6E666666--

JCCLARK wrote:

Bruce2 wrote:Im repainting a truck and i stripped it to bare metal and this weekend i shot some primer on it Mar Hyde 2k.

I hope you didn't spray that 2k directly over bare metal, that 2k isn't made for that.
It needs an etch or epoxy first.
If not, it may peel off later.

http://multimedia.3m.com/mws/mediawebse ... 6E666666--

Yep pretty much bare metal,,,was told when i bought it i could shoot it on bare metal...bady was in primer state when we got it and i sanded it all back down to metal because of the deterioration of the primer.