Thread: nube with 2 many q's please help.

well first an intro. i want to spray Duracoat on weapons, MX parts ect. its a resin that dries to touch in an hour. also would like to get creative with models adn helmets ect. i know time is my best asset with this. her eis the q's. adn my brush is a paache vl series. comes with 3 tips 1, 3, 5.
what tip is best used with a resin type material ??
tried to use some testors enamel with my sons model car adn getting spatter with the 1 tip the cone is slotted ?? why . teh 3 does ok but very touchy
adn what pressure is best for model enamel ? i know when teh duracoat arrives i need to try different pressure settings. but still dont know what tip to start . been practicing the mechanics of the brush, so far getting comfortable. tips ideas ect appreciated

First, you need to understand the balance of three elements or factors you have to deal with in airbrushing. Paint viscosity, needle and nozzle size, and air pressure. Actually there is a fourth element too, and that is whether your airbrush is siphon fed or gravity fed, but we'll talk about that in a bit.

The thicker or heavier viscosity your paint is the more air pressure it takes to atomize/spray it. The smaller the nozzle and needle size, the touchier the airbrush will be as far as viscosity goes, but the easier it will be for that same setup to do detail (Providing all the other elements are in balance.). The higher the pressure, the thicker/heavier the paint you can spray, but the higher the pressure, the more overspray you get too. That higher air pressure also requires more labor and capacity by your air compressor or propellant souce. Inversely, the thinner the paint or colorant, the less airpressure you need to spray it, and the less overspray you end up with. If our paint is too thin, it may not adhere or cover very well, too thick and it may not spray very well.
For most painters, they tend to reduce/thin their paint down to about the consistancy of milk, then mix it and strain it before it goes into their brush. Then start with your air pressure at about 20psi, do some test spraying then adjust the pressure up or down 'til your airbrush sprays the paint properly.

Some paints can't be reduced that much, so it means that you will have to increase the air pressure, and maybe go with the larger nozzle setup.

There are primarily two methods of feeding paint to your brush, gravity or siphon/suction.
Gravity feed brushes have gravity working for them pushing paint down into the path of the air as it exits the nozzle cap. Gravity feed brushes tend to have the cup permenantly fixed to the top of the airbrush.
Siphon or suction feed brushes depend on a siphon or suction/vacuum action to pull the paint from a cup or reservoir that sits below the airbrush, and because of that, it means that they need additional air pressure to make them spray. Siphon fed brushes let you have the reservoir out of the line of site for the painter, and let you use a variety of different sizes and types of reservoirs.

For the enamels you mentioned, you should be able to reduce them a good bit so that they will spray nicely from your brush, even with the #1 setup installed.
For the other finish, I am not familiar with it so it's tough for me to tell you much. However, I would take a look at the solvents in the finish and it's cleaners, and see if they are compatable with the airbrush and it's seals and packing. I would make sure that you can completely clean the brush before you ever let it get near that finish.
Having your brush packed with a dried and hardened resin or epoxy is an expensive lesson to learn.
If your Paasche is an older one, it will have rubber seals and packing, and they may not do well with the finish you are proposing to use.
Do your homework before you think about spraying it.
Also make sure you have the proper safety gear to protect you and your environment when you are spraying it or any other paint or finish.

OK, its a new air brush. siphon feed. I am trying to use around 20 psi for the enamel ( testors) tried to thin but still same fine splatter and almost dry at contact using teh # 1 tip I assume teh smaller teh # tips teh smaller teh lines ? I do clean very well complete take apart. I think teh resin will do ok wtih a medium tip #3 it arrives today adn ill try it out tonight. teh enamel is my problem for fine line detail on models. mabye i thinned 2 much or its still 2 much air ?

Try turning up your air pressure, it sounds like you (your airbrsuh) are not atomizing the paint, so rather than getting the fine mist you want, it sprays it out in splatters.
If your paint is properly mixed, reduced, and strained, and your airbrush is in good shape this should do the trick.

Hopefully your compressor can go to higher pressures, if not then you need to get another compressor or propellant source.
This is why we preach for people to look at what they are going to use an airbrush for, it's requirements, the paint(s) they will need or want to use and their requirements, then use that criteria to go out and shop for their airbrush(es) and compressor.

As to the spraying of fine lines, keep in mind that almost all airbrushes are supposed to spray the paint out in the shape of a cone, with the point of the cone at the tip of the airbrush and the wide circular end of the cone falling on the surface you are painting. So with that in mind the closer you have the airbrush to the work surface the smaller the circle of paint (at the bottom of the cone). That circle will have the paint feather out from the center. You can actually get some nice fine lines with the #5 setup on your brush, but it takes some practice and dilligence.
I would do lots of practice on paper using less toxic and less expensive paints 'til you have your skills down solidly. Do your practice and learning using only black paint, it gives you the most honest results, and helps you avoid the distraction of the various colors and effects. Work on your dots, dagger strokes, lines, and basic shading until you can do them without having to stop and think about what you should be doing with your hands, etc. The airbrush should become an extension of your hands and mind.

thanks, i also found another problem is my regulator on my shop compresser. got a better regulator, side fed it for air brush leaving teh other for shop tools. much better results, not too hard then bleeding down to not enugh, i will be practicing, i will try the # 5 instead of the #1 thanks . will let you know how i am doing later on.

I'm not sure I understand what you mean when you say you "Sidefed" it.
You need to make sure your air is clean as well as regulated, and you need to make sure your paint is properly reduced, mixed, and strained before it goes into your brush.
With the paint properly prepped it should be sprayable with the #1 needle and nozzle setup without any problem.
Just make sure you use the right reducer/thinner, using something like laquer thinner will destroy the paint, and probably the plastic models too!