Model Flex paints

[ATSF_Ron]

I read on this forum recently that Model Flex paints are still available (or again available?) from Badger.  If memory serves correctly, I also read years ago that the original recipe tended to flake off after some time, so I quit using them and just assumed they quit making them.  Anyhow, I bought a weathering set on Amazon recently and they have arrived.  On the bottle it says "water based acrylic hobby paint film."  My question is do you need their specific cleaner or thinner to prepare the paint for airbrushing/cleanup?  If memory serves, I believe when I used these decades ago I just thinned with water.  It does, after all, say "water based" on the bottle.  This was the original recipe.  Would it be ok to just use water for these?  Hopefully I can.  I have so many different types of paint and thinners around here it's crazy!  Thanks.





I'm using the earth color for a brick building in the works.  I wanted something different from a "standard red brick" color.

[thomasjmdavis]

All my humble opinion, your mileage may very.

I use a lot of Modelflex.  It is better than it was in the early days.  Also, they gave up years ago telling people they did not need primer. Clean, oil free surface is a must. I use a Paasche VL (internal mix, double action) airbrush, generally with a number 3 tip. My experience is that if you want to thin, you are best served by using their thinner. Look at it this way- if the paint is 80% water (I don't know the actual percentage, this is for example only), you want to thin it with the thinner, which has a similar water content. If you thin with water, you end up with paint that is 90% or 95% water, and will not adhere as well, is more likely to flake, etc.  If you are staining wood, water is fine as a thinner, but for paint on plastics or metal, go with the thinner (IMHO).

In general, I find that I don't need to thin the paint to be able to airbrush it, when it's new. (most of the time, and earth colors seem thicker than bright colors)  If the color is too intense for weathering, I sometimes mix with clear flat, to get a more translucent color without watering down.

I also highly recommend their "Stynylrez" primer if painting plastics or resins (and I've even had pretty good results over metal). It is available in several colors. It adheres very well to plastics (Stynylrez= styrene,nylon, resin). Use white under yellow or pastels, oxide under reds and browns, etc.

One last thing- several light coats. The first one will probably look terrible, but after a few coats, it "skins" over and you end up with a thin, even coating.

[nscaler711]

All my humble opinion, your mileage may very.

I use a lot of Modelflex.  It is better than it was in the early days.  Also, they gave up years ago telling people they did not need primer. Clean, oil free surface is a must. I use a Paasche VL (internal mix, double action) airbrush, generally with a number 3 tip. My experience is that if you want to thin, you are best served by using their thinner. Look at it this way- if the paint is 80% water (I don't know the actual percentage, this is for example only), you want to thin it with the thinner, which has a similar water content. If you thin with water, you end up with paint that is 90% or 95% water, and will not adhere as well, is more likely to flake, etc.  If you are staining wood, water is fine as a thinner, but for paint on plastics or metal, go with the thinner (IMHO).

In general, I find that I don't need to thin the paint to be able to airbrush it, when it's new. (most of the time, and earth colors seem thicker than bright colors)  If the color is too intense for weathering, I sometimes mix with clear flat, to get a more translucent color without watering down.

I also highly recommend their "Stynylrez" primer if painting plastics or resins (and I've even had pretty good results over metal). It is available in several colors. It adheres very well to plastics (Stynylrez= styrene,nylon, resin). Use white under yellow or pastels, oxide under reds and browns, etc.

One last thing- several light coats. The first one will probably look terrible, but after a few coats, it "skins" over and you end up with a thin, even coating.

I just want to add, if you are painting Delrin, or any plastic like Delrin, and Automotive paint primer is key for paint adhesion. The stuff is designed to flex with the material its on, usually plastic like your bumper covers.

[wazzou]

I just want to add, if you are painting Delrin, or any plastic like Delrin, and Automotive paint primer is key for paint adhesion. The stuff is designed to flex with the material its on, usually plastic like your bumper covers.

Adhesion Promoter.

[daniel_leavitt2000]

I use Tamiya thinner on my Model Flex paints.

[ATSF_Ron]

I’ve got some Vallejo thinner arriving today. The problem now is the cleanup 🤦🏻‍♂️
Everything dries so fast! The tip won’t clean up with water or isopropyl alcohol. I may need some retarder as well.

[peteski]

I’ve got some Vallejo thinner arriving today. The problem now is the cleanup 🤦🏻‍♂️
Everything dries so fast! The tip won’t clean up with water or isopropyl alcohol. I may need some retarder as well.

Lacquer thinner should do the trick, but it will likely not dissolve the dried enamel, but just make it soft and rubbery.  That is the problem with enamel paints - they set by a chemical reaction, not just by solvent evaporation like lacquers do.  I heard ammonia also softens those enamels, but it can also attach brass parts of the airbrush.  This is the main reason I don't airbrush water-based enamels.  I still airbrush old-school stinky paints.

[thomasjmdavis]

All I have ever done to clean Modelflex from the airbrush is to soak the parts in alcohol (I use 91%) for a few minutes, then use the cleaning brushes (which came with my Paasche kit 10 years ago) to remove anything that is stubborn. Only takes a minute or two.  Then I spray warm water through it.  If the paint hasn't dried yet, spraying warm/hot water through is generally sufficient by itself (as when I am changing colors).  Again, that is my Paasche VL, YMMV.

Here are the Badger recommendations-
https://badgerairbrush.com/PDF/ModelFlex%20032613.pdf
Note their recommendation on air pressure. 

@ATSF_Ron  - what airbrush are you using?  Internal mix or external?  Tip size?

@ Peteski- Modelflex is not like any enamel I've ever used. Much more like the latex and acrylic paints that were common in the days before we had "latex enamel" or "acrylic enamel" paints on the market. That is to say, it is a very thin flexible skin, not a hard shell, after it dries.  if separate from a surface, it will stretch.  A quick web search brought up the following definition for enamel paints-

Enamel paint is defined more by its qualities than by its content. In the broadest sense, enamel paint means any solvent-based paint that dries to a hard, vitreous-like (or, glass-like) shell. Solvent-based paints are also called oil-based paints, in contrast with water-based paints.

Modelflex is water based, and not a "hard shell".

[ATSF_Ron]

Tom, I have a badger model 200 which is internal mix. My tip is “heavy.“ I will try the alcohol soak again and get an old toothbrush to scrub. If that doesn’t work, then it’s out to the garage with stinky mineral spirits. 😂

Peteski, I like the quality of the stinky paints, I just don’t like all of the cleanup and the smell.

[peteski]

Peteski, I like the quality of the stinky paints, I just don’t like all of the cleanup and the smell.

But the cleanup of stinky paints is super easy (compared to water-based acrylic/latex paints).  All it needs is a rinse and blow-through with lacquer thinner coupler of times, right after paint session.  I do a complete strip down of the airbrush (when I actually actively paint things) maybe once a year.  I should really make a video of my airbrush flushing procedure.

Here is a copy of a post I made few years ago:
I've been using a Badger 200 siphon feed airbrush for 20 years and cleaning was never a chore. After painting I just put in about 4 pipette's worth of  lacquer thinner in the paint jar and swirl it around to wash the paint off the jar's walls. Then I spray that liquid out into a paper towel while constantly opening and closing the needle.  Then I put in 3 more pipette's worth of lacquer thinner in the jar and again swirl it. At this point the liquid is almost clear.  I again spray it out of the airbrush but this time I repeatedly cover the nozzle with a paper towel while spraying. That deflects the lacquer thinner into the nozzle, rinsing it out. I also fully cover the nozzle while spraying which causes the air to come out through the siphon tube. The I repeat the process of putting some thinner in the jar for the third time (it it now clear) and fully spraying it out of the jar without obstructing the nozzle.

This whole process takes about 1 minute and it is very easy.   I do fully disassemble the airbrush but that happens less than twice a year.  However I only use organic-solvent based paints (not water based acrylics). I have not yet graduated to spraying water-based paints.  I'm not planning on it either - I like the old fashion smelly paints.