Help with airbrushing please

The rule of thumb is about 10-15% but Testors is kind of thick so maybe a bit more. A lot of experienced users suggest it should be about the consistency of skim milk. To be honest, I just sort of eyeball it from experience, but the above should at least give you a starting point. Thinner paint will give you faster drying and easier spraying, but require more coats. Be sure to clean the airbrush thoroughly IMMEDIATELY after painting; Testors is a real PITA to clean up if it dries in the airbrush. 

Joe,

Do you much experience with your airbrush? Enamels require patience and plenty of practice to spray correctly. Enamels can and will gum up your airbrush faster than anything. Not only that, the required tear-down and cleaning of your equipment make enamels a poor choice. Your best bet would be a rattle can. I hope this helps.

"Pappy"

Like skim milk is what I do. I air brushed enamels for 30 years with no issues. Tried to switch to acrylics and had nothing but issues and clogged air brushes. To each his own I reckon!  

It is imperative to keep the airbrush clean at all times especially around the nozzle tip. After each use I spray a good quantity of solvent through the brush.

then when necessary I break the brush down for a thorough cleaning.

the spray depends on the thinning and the air pressure used.

Bob C.

Hi Coach Joe • I spray a lot of Acrylic on rock castings & for weathering. Not a big fan of testers, because of the fumes. Leaves a bad smell in the house. If I do spray enamels or lacquers, have to go out to the garage. 50/50 starting ratio. This is a photo of my Binks Airbrush.

   Click photo to enlarge

Also depends on what you're doing. Are you actually painting something to change the color, or weathering as in a color fade or coat of dirt and grime.

Also depends on the needle and tip of your airbrush. Is it really fine, or a medium, to heavy tip. The finer the tip/needle, the thinner your paint will need to be.

With that enamel being so thick, I'd start at about 3 parts paint, 1 part thinner... and that's probably going to need more thinner.

Ditto.

Regardless of what type paint you use you'll still need to clean the airbrush and keep it clean.  DON'T use old paint that's been opened (more than a year old for me).

I'm almost exclusively using acrylics these days and the skim milk reference has worked fine so far.  Also use paint manufacturers thinner instead of cutting corners with substitutes.

I thin enamels 2 parts paint and one part thinner, or with some alkyd enamels I use naptha. I have not found that enamels gum up air brushes at all. I wait 5-10 minutes bettween coats with no issues.

There are some great airbrush and paint thinning videos on youtube. One of the videos about thinning paint will make you a master in no time.

Rob

For the novice air brush hobbyist.

You can buy an air compressor with tanks relatively cheap.  This was purchased from PepBoys via a Sunday newspaper ad.  Click on the underlined phrase to link to a similar offering.  My Compressor pictured is not oil-less.  It requires addition of compressor oil from time to time.  The purchase of an air hose and the Quick-attachment parts added 1/2 again the cost of the compressor.  Most small motored tools, like this, 1/3 to 1/2 horsepower, should be powered via a 12 gauge 20 amp circuit. IMO.  Proper operation requires the tank(s) be drained of condensation water and excess oil periodically . 

Previous Air brush post. 
I posted this set of picture some time ago.  Needed items for an air brush.
Cleaners, containers and several different bottles.


I have a quick-tach system so that I can connect different air tools .  Also note the water separator top of picture.


Water separator


A slop bucket, where I start the air brush, and eventually clean it.


Adequate work area and a fabricated air brush holder that is in a portable vice.


Note that the air compressor will have two air pressure gauges. Tank pressure and air brush pressure.  Adjustable with the screw knob.


I have a second water separator at the air compressor.


A good hose that works for all air needs, filling tires etc.  Note the quick-tach system again.


Q-tips and paper towel for cleaning.  I also find pipe cleaners useful for brush and tube cleaning.


Most important, either a very good air ventilation system or an organic cartridge type respirator.  Or BOTH.


I also have a very good slop sink in the work area with hot and cold water for clean up. Upper left corner of this picture.

Posted in another thread.  Please be careful with all materials used as part of Model Railroading.  Mike CT

Safety meeting for the day. I had posted this a few years ago, part of an airbrush thread.   The material used for painting and paint removal need safety precautions.  All would have an associated MSDS.  Material Safety Data Sheet. Surprisingly Water clean-up acrylic paints, cleaners, and thinners can be issues.  I eventually purchased an organic cartridge respirator.  Eye protection is also a good thing.  Noted that I usually felt better at the end of the day.
This was added as part of the safety discussion.

quote:

Originally posted by OntarioRailFan: I've got a good paint booth vented directly outside. I also use ONLY water based paint.  Though I have not used a respirator.  Is this something I should add before I start my next round of painting????

YES From my shelf, what is written on the bottles.

Badger Modelflex acrylic paint  Non-toxic. Keep out of the reach of children. If ingested do not induce vomiting. Call a physician immediately.

Polyscale  (now ModelMaster) acrylic model RR paint Non-toxic. Contains Isobutanol and DPNB. Causes eye irritation. Avoid eye contact.  First Aid: For eye contact flush immediately with plenty of water. Not intended for use by children

Polyscale (now ModelMaster) acrylic thinner  No caution listed.

Polyscale (now ModelMaster) acrylic cleaner  May irritate eyes Do not get in eyes. Do not take internally. Close container after each use. Keep out of reach of children.  First aid treatment : Contains gylcol ethers. If swallowed call a physician or poison control center immediately.  In case of eye contact, flush with plenty of water.

Weaver ScalecoatI Paint Danger Flammable Harmful or fatal if swallowed vapor harmful Read addional caution on back of label. Contains Zylene, Benzene, Butanone Oxime, and Petroleum Distillates that may be harmful if misused. Read caution on individual containers carefully. Harmful or fatal if swallowed. If swallowed do not induce vomiting. Call Physician immediately. Vapor harmful, May be harmful by breathing vapor. Use proper ventilation. When using,do not eat, drink, or smoke. Wash hands immediately after use. Avoid skin contact.  Keep container tightly closed when not in use. Do not use on interior surfaces. For use on model train cars and hobby related models only. FIRST AID: In case of eye contact thoroughly flush with water for 15 minutes and get medical attention.  For skin contact wash thoroughly with soap and water. In case of respiratory difficulty, provide fresh air and call physician. Call 1 800 424 9300 for more health information FLAMABLE: Keep away from heat, sparks, and open flame. WARNING This product contains chemicals known to the State of Californina to cause cancer and birth defects or other reproductive harm. KEEP OUT OF THE REACH OF CHILDREN.  (Ya, that's all on that one ounce bottle of paint).

Floquil Railroad Colors For Emergency Health Information call 1 800 962 1253. Contains petroleum distillates. Vapor Harmful Keep away from heat, sparks and open flame. Causes eye and skin irritation. To avoid breathin vapors and spray mist, open windows and doors to ensure fresh aire entry during application and drying. If you experience eye watering, headaches, or dizziness, increase fresh air or wear respiratory protection. Close container after each use. Avoid contact with eyes and skin. USE WITH ADEQUATE VENTILATION. WARNING this product contains chemicals know to the State of California to cause cancer and birth defects or other reproductive harm. FIRST AID: If swallowed. Do not induce vomiting. Call physcian immediately. KEEP OUT OF REACH OF CHILDREN.

Floquil air brush thinner CONTENTS AND FUMES MAY CATCH FIRE. CONTENTS HARMFUL. MAY IRRITATE EYES AND SKIN. KEEP OUT OF REACH OF CHILDREN.  Vapors may ignite explosively. vapors harmful. May affect the brain and nervous system. causing dizziness, headache, or nausea. Causes eye, skin, nose, and throat irritation. Keep away from heat and flame. Avoid eye contact. Avoid breathing vapors and spray mist. Use only in well-ventilated area. Wash thoroughly after handling. Intentional misuse by deliberate concentrating and inhaling the contents may be harmful or fatal. FIRST AID: Contains petroleum distillates and n-propoxypropanol. In case of eye contact, flush with plenty of water for 15 minutes. If swallowd call physician ofr Poison Control Center immediately. If inhaled, seek fresh air. If on skin, rinse well with water. There are a lot of other chemicals on the shelf. All with some kind of a caution. IMO At the bare minimum even using acrylic, water clean up, paints adequate ventalition should be provided. This was part of a larger discussion at the time that moved toward full face protection,(eyes),and a filtering system that pulls or inhibits breathing any of the chemicals present.  There has also been several threads on model spray paint booths. Spray Booth currently on the 2 Rail Forum.    Mike
Respirator from a local auto parts or body shop paint supply.  Note that the two cartridges are designed to be replaced periodically.  $30 to $50 maybe ????

Thanks to all that answered my question.  I'll try 3-1 and see how it goes.

Although you will hear people say do not do it, I have seen a master model builder use laquer thinner with testors enamel mixed two parts paint and one part thinner. The paint was dry in ten minutes. I tried it with alkyd enamel, same mix, and it flowed great but took around 20 hours to be really dry. Mix thinner 2-1 with enamels and you won't have problems. Use at least a number three nozzle, I like number 5.

Rob

Have guys tell me all the time to try that....never have...but the love it!

for starters build a strip tank first, and practice ,practice ,practice.  I am just beating my head against a wall with my model for Chicago 2 rail show, and after 2 strips I'm sold on the new tru-color paint, sprays straight out of the bottle! just had to modify a cap for my pasche single action. alas gone is my floquil. With the wide variety of Tuscan red available was surprised that this paint matched all of my older vintage built stuff more redder than the newer brown tuscans available. Going to tryNP light and dark green next have quite a few to paint.

Lots of great tips.

If you like enamels try thinning with acrylic Lacquer Thinner. The stuff works incredibly well and when run straight through your airbrush cleans up everything!!

BUT

Technology of acrylics has come light years. Look into a company called "Vellejo" from Spain I recently started to use their paints for my son's model airplanes and they are SO good and SO easy to use I plan to sell off almost all my enamels!!!

There is another company from Poland "Hataka" which has really good reviews.

I am switching to acrylics(something I thought I would never do) because the technology has so vastly improved they look realistic, thin with water(distilled) or denatured alcohol, are non-toxic , non-explosive, and truly clean up with soap and water!!! Most of the time you can spray right out of the bottle!!!!!

I am teaching my 11 year old son to paint and I won't have to worry about him spilling chemicals, burning or blowing up the house!!

The best model rail road paint I found is TRU-COLOR. The paint is dry, and sandable in 30 minutes! It  uses acetone to thin. If you need a color and they have it you will love it. You can tape and spray different colors in one day!

Rob

Badger Modelflex is another decent acrylic paint.  There are railroad colors.

I have had a lot of trouble with Badger paints drying out in the bottle, even if the bottle has never been opened. So far I've caught the process in time to save the paint with distilled water and a lot of stirring, but it's a nuisance. Also, Badger paints don't spray as well for me as other brands. I have quite a few bottles and I still use them occasionally, but I won't be buying any more. 

Two comments to add.

-do not paint near any source of flame, like a hot water heater or a clothes drier.

-to clean the airbrush, it must be disassembled. Just running thinner through it afterwards will not do the job.

Again thank you everyone.

Ditto Bob's ditto!

Just to let you know that the 'skim milk' analogy works fairly well, I used my Paasche H (single action) to spray Behr (Home Depot) Interior Latex paint during a multi-room repaint.  The wall-mounted sheet metal grills for the forced air system didn't look acceptable after a brush or roller application.  I thinned the latex to the 'skim milk' consistency....shaboom!...Perfect patina match to the walls!   They were done outdoors... in better weather than this winter is serving up, that's for sure!!

Although I have a spray booth in my workshop, I prefer acrylics for the ease of clean-up (Windex and/or water) and the reduced odor.  The new RR paints by Tru-Color, however, have an acetone base, and I'm really liking the quality of the finish when airbrushed.  I guess I'll have to warp the paradigm, so to speak. 

FWIW, always.

KD

If you paint those beautiful UP passenger cars I'll be forced to drive to your house to save them - all the way from IN. 

KD ...... are you happy with your Paasche H airbrush?

I'm about to take the plunge into airbrushing my trains .... both O and HO .... and was going to buy that model. Am I correct that it is a simple to use, quality airbrush that has been around for a long time?

Looks like I will be using Tru-Color paints exclusively.

Thanks

Jim

I have found ScaleCoat 2 is really easy to use, the color is great. I thin it with whatever I have, usually mineral spirits. 80-20 works in my 2 stage badger.

Dick