What to use as a replacement of Tamiye acrylic thinner?

I'd stay away from using Windex as a thinner.  The amonia chemically breaks down the acrylics paint which makes it great for cleaning brushes, air brushes, spray booth and for stripping even dried acrylic paint.

Isopropyl alcohol is a good substitute for Tamiya Thinner, however keep in mind that the Tamiya product contains a retarder which prevents the paint from drying too quickly.  You might get a grainy finish if you hold the airbrush too far back and the paint dries as it's propelled through the air onto the model. 

I've used the windshield wiper fluid with great results.

Steve

Thanks Phil!

You'ver beginning to make me feel like "The Mighty Carnak" (for those who remember Johnny Carson…) 

Triarius wrote:

I've been told that Tamiya acrylic thinner is essentially isopropyl alcohol with a retarder, though I haven't seen it's MSDS or actual composition. I suspect it may also have a glycol compound in it.

I use Isopropyl Alchohol with a drop of dish soap as a retarder.

Jose

I'll pass this along from another site. (And I quote)

Windshield washer fluid

To thin acrylic paint, I use automotive windshield washer fluid. The generic cheap blue kind that's $1.00 for a 1 gallon jug. It contains glycol, water, and detergent. It works excellently with Tamiya and Model Master Acryl paints. It has the same ingredients as Tamiya thinner, which, as I priced yesterday, is $128.00 a gallon at the LHS.

Windex

To clean my airbrush, I use the generic economy brand equivalent of Windex window cleaner. It dissolves acrylic paint like a magic eraser. When I'm done with a color, I wipe out the cup and shoot Windex through the brush until it comes out completely clean. That's it. I only take my airbrushes (an Iwata and a Tamiya) apart once a year to give them a good cleaning.

Windex is also a rescuer if you botch your paint job. Just place the model in a tupperware and fill with Windex to cover the model. Leave it overnight and in the morning all the paint will be gone, leaving you a clean slate to try again.

I don't know where you get windshield washer fluid in Israel.

Dan

Since I use the TLAR method of mixing paint right in the paint cup of my airbrush it isn't very exacting. But I do get good results!

What I do though is add a squirt of alcohol (90% iso) into the cup followed by the paint. I add more alcohol until I get the consistancy I desire, then add one drop of a Windex solution (50/50 Windex/water). This seams to allow for a more consistant flowage throughout the spraying session with the color, especially if you are starting and stopping to reposition or work with different parts. The alcohol also evaporates rather quickly so you may end up adding more if you're painting a large area.

I'll chime in with another nod for 90% or better Isopropyl Alcohol. In a pinch you could use the 70% version, but beware that there could be other chemicals mixed in that may be incompatable with the paint.

An acrylic retarder is a good idea to prevent tip dry. Using alcohol have a tendency to flatten gloss paints.

I have us 90% alcohol as well, it works ok. Another option is wind screen wiper fluid (winter mix, it must cntain alcohol!) I have also mixed the two with ok results.

Basically the Tamiya thinner is a alcohol/water solution (probably around 60% alcohol but that's a guess) with some retarder added. Most other alcohol/water mixes work just as well. Just stay away from the ammonia, it attacks acryllic paints (good for cleaning though)

While some people swear by Windex as a thinner for Tamiya acrylics, I won't use it. Whilst Windex contains an amount of alcohol, which is an effective thinner for Tamiya acrylics, it also contains some ammonia, which is very effective at breaking down the binders in the paint which make it adhere to the surface being painted. Many people use Windex to clean their airbrushes specifically for its ability to break down acrylic paint.

The best thinner for Tamiya acrylic is Tamiya's own thinner. However, if unavailable, the best alternative is (90% or better) Isopropyl alcohol. The next best option is ethanol (aka denatured alcohol or methylated spirits in some localities).

Both of these options can be somewhat problematic when airbrushing due to the fast evaporation of the alcohol. This can sometimes cause a grainy, powdery finish due to paint drying in the air between the airbrush and the surface of the model being painted. This can be reduced by airbrushing closer to the surface of the model and by adding an acrylic retarder (available from art supply stores) to your paint mix (pre-mix a few drops of retarder with your chosen thinner before mixing with your paint). Typically, I spray from 15cm or less.

Whilst I haven't had any problems using ethanol as a thinner, Ross (Triarius) has indicated that there may be some compatibility issues with certain colours in the range, so I'd suggest testing with small amounts first.