Cheap "savebarn" hvlp spray guns

ltz500, Aug 13, 3:35am
Recently bought one of these to prime some old machinery and truck parts. Bastard thing wont spray properly, primer comes out all blotchy and sounds like the gun is cavitating. Have played around with fan and fluid adjustments but cannot seem to get this f'ing thing working properly. Something I'm doing wrong or are they just cheap crap? Never had this issue with my old siphon feed guns. Thanks
m16d, Aug 13, 4:33am
More pressure.
gunhand, Aug 13, 4:54am
Paint / primer to thick? pressure wrong? should be round 30psi. Gun air cap blocked? Screw fluid adjuster all the way out. Does it start working ok with just thinners?
Are you using 2pak products?
These guns while cheap can do a quite reasonable job. May not last forever mind you.
unclejake, Aug 13, 6:29am
Everything I've bought from Savebarn has been great (so far)

The gun problem could be too small a fluid tip for the product (try spraying some water to see if it's better), a blocked vent (in the screw on cap), or other contamination. but of course it could be faulty.Good luck.

EDIT: What Gunhand said. Ooops. I should have read that first.

One more point though - I've found that if I run a gravity feed gun dry with two pack paint I'll almost instantly have a problem. The same didn't occur with siphon guns for me
ltz500, Aug 13, 7:06am
Thanks for the replys. Just had another play with it ,pulled it all apart and made sure all passages were clean. Filled it with water and left the lid off. Just wont supply a constant mist of paint. Have the pressure set at 30 psi. Tried 40 psi but still the same problem. Think its heading for the bin lol.
grangies, Aug 13, 7:11am
Can you post a link to the actual type of gun.

Coming out blotchy? As in intermittent? .

Sounds like the fluid nozzle and/or the air cap is not tight enough.
ltz500, Aug 13, 10:26am
attitudedesignz, Aug 13, 8:13pm
Also, check needle is straight. And seating in fluid cap correctly.
rob_man, Aug 14, 12:02am
There is a gland where the needle goes through the back of the body of the gun, in front of the trigger. Most guns have a hex adjusting method which tightens the gland onto the needle preventing what is the same effect as a vacuum leak in a carburettor. First of all, lube the needle so there's a minimum of friction, then tighten the nut until the needle locks up. Slacken it off until it's free and that should cure your problem.
It could also be the fluid nozzle not seating properly with the air cap.
ltz500, Aug 15, 8:42am
thanks. going to buy one of those guns. so im better off going for the 1.8 tip instead of a 1.3 tip?
grangies, Aug 15, 8:55am
For primer and machinery and truck components . Yes 1.8 is best, as it can throw a lot of thick paint out.

The Iwata W71 is made completely in Japan (some Iwata guns are made in Italy too) , and the Iwata brand is a premium product.

Iwata is up there in the top
spray gun manufactures world wide. Possibly even the top 3.

In spray painting businesses in NZ it's almost guaranteed that they paint with either Iwata, Devilbiss or Sata guns.
gunhand, Aug 15, 9:01am
Of those choices use 1.8 for priming. 1.3 with thinned primer will put it on nice and smooth and makes it easy to sand mind you.
I used a 3 tip today for priming, but I did want a jolly good layer of primer.
I use an Iwata 1.4 gun and its coming up 10 years old (or there abouts) and hasn't givin me any issue at all. And its used day in day out.
unclejake, Aug 15, 11:44am
3 as in 3.0mm? Lordy. I use my 2.5mm for Sikkens spraybog, and that's a pretty thick compound. You mush ave had some thick ooze there son. LOL
gunhand, Aug 15, 9:54pm
Yep, generally used it for spray bog lol, but in this instance a thick layer of primer was required. Doesn't pay to move to slowly with it.
horsygirl, Aug 15, 10:23pm
The joys of Labours Free Trade Agreement with China.
ltz500, Aug 16, 11:17am
Thanks guys, definately buying an iwata gun.

I would like to purchase one that I can use to do some top coating aswell. Will be spraying epoxy enamel ( and maybe some automotive paints once my skills improve), will the 1.8 tip still be alright for this sort of stuff?

Thanks for the help
gmphil, Aug 16, 11:49am
my mates a pro boat painter he uses iwata and loves it .
stevo2, Aug 16, 6:57pm
My Iwata W-77 has a 2mm tip. It was in there when I bought it (used) from a car painter friend.
Would you say the 2mm is a bit big for general purpose priming and top coats?
I dont spray much anymore but Ive sprayed Reaction Lacquer, Acran, Dulux sprayin enamel, Resenes Uracryl etc. mostly 2 pack, on automotive, marine and kitchens.
grangies, Oct 3, 6:17pm
The 2.0mm tip all depends on your spraying ability and knowledge of setting the gun up for certain paints.

A 2.0mm tip could get away with 2K colours and clears as long as the fluid adjustment is only open about 1/3-1/2 of it's capacity. And just let the paint dry for longer between coats to prevent solvent boil (where the top surface dries and traps the wet paint underneath) .

I personally would never use a 2.0mm for anything other than primers. But that is because I have a wide range of 1.3 and 1.4 guns available. But if I had to use 2.0mm I set the gun up accordingly.

Never try and use a 2.0mm for metallic base coats, it's just too heavy and will make a mess, and use too much expensive colour.

Iwata have a new range of guns, which are gravity fed and well under $300 retail. They are the Airgunso AZ3 models from Italy, and come in 1.3, 1.5 and 1.8. Great guns for their price.