General spray gun questions

[Ken Garlock]

Jim Becker, since the question of spraying came up, would you be so kind as to put together a users guide for using a spray gun. By that I don't mean the manual of operation that comes with a particular gun, but rather the considerations that apply to any gun.

I know how to spell spray gun, but that is about all I know. Some of the things I would be interested in are very basic HVLP items.

What are the different nozzle sizes when do I need a specific size?

What is the consistency of the paint for spraying, how do I measure it?

Do you filter the paint prior to putting it in the gun? If so, how?

Cleaning the gun after use. How much thinner do you run through it? Until it sprays clean on a white surface?

Water traps on the air line, are they needed and what kind.

From time to time I see questions of this nature posted. It would be nice to have a quick reference available in the articles section.

Perhaps there is one or more books available on the subject, if so what do you recommend(your way out )

[Jim Becker]

Ken, I can probably address most of those questions in general, but I am far from any level of expertise. Hopefully, whatever I come up with will be useful to most folks. I'll try and post it in a few days.

[Cecil Arnold]

While Jim will put together a much more complete list I'll give you some quick and dirty answers based on my limited use of HVLP.

1. Nozzle sizes on HPLV guns are a function of paint viscosity. My gun supplier included a cup (with a hole in the bottom) to determine viscosity. A filled cup takes X seconds to drain, That time will determine the tip size or the need for thining. I think (and think is the key word) that different gun manufacturers use different tip sizes so what works for a Fuji will be different from another brand, ie Fuji number 2 tip is not the same as Turbineair's. That should give you info on your first two questions.

2. The paint supplier I have delt with in the past, Compliant Systems, includes a nylon footlet (women's foot apperal) to use as a filter for their pre cat water based laquer. Other paints, such as nitro cell laquer, should be strained through a paper/cheese cloth filter available at Sears.

3. Depending on what type paint you are using, you would run the appropriate solvent through the gun cup, then tear down the gun and finish cleaning it. You will need several brushes, round and flat, and possibly some wooden toothpicks.

4. I don't know squat about water traps. I'm using a turbine compressor and the hot air that comes out of that is too warm to support much in the way of water. A conversion gun, using a regulair compressor might need one.

FYI, I have used nitro cell laquer, water based laquer, water based pigmented enamel, and shellac in my rig with good results limited only by the skill of the nut behind the trigger.

[Kirk (KC) Constable]

...I know how to spell spray gun, but that is about all I know...

Ken...you might want to edit your post title to back up this claim.

KC

[Ken Garlock]

Ken...you might want to edit your post title to back up this claim.

KC

Good catch Kirk.