Tamiya Acrylics and thinning

[Guest]

I have a bit of a conscience problem (yes, contrary to popular opinion, I do have a conscience....) Anyway. Some time ago, sorry I cannot remember who, mentioned thinning Tamiya Acrylics with Lacquer (Cellulose). I remember saying at the time that this was a no no as the thinners was far too hot for thinning Acrylic paint.

Having viewed the superb DVD I bought from the forum shop on Modulation Style I was totally shocked and surprised when it was stated that "even though Tamiya paints are sold as Acrylic, they are actually designed to be thinned with lacquer thinners' (not an exact quote).

Anyway, I put it to the back of my mind and tried to forget about it. However, when I was in my shed tonight my curiosity got the better of me and I decided to see what would happen.

As per the video, that was mixing paint thinly so that it could be transparent for shading, I made a mix of Tamiya Olive Drab 40% and Halfords cellulose thinners 60% in a small cup expecting some odd reaction. Nothing happened, it mixed together with no splitting that I expected. So, I poured it into the airbrush and did a spray onto card,it spayed quite nicely. I then moved on to a scrap 1:72 kit and gradually built up a layer of colour, it really is transparent and builds up wonderfully.

So, what is going on here? First of all I apologise for stamping on the idea that this combination could be used. Secondly, common sense says that this should be a disaster in the making but the finish was smooth and really nice.

What I don't understand is why???????

[Guest]

I do know that Tamiya Acrylics are not true acrylics in the sense of water based which will be why you didn't get any splitting, (theoretically this means enamel thinners could be used I guess, or white spirit / turps etc?)

Other than that I don't know, maybe Ray's the man to unravel the technical aspects for us?

Aside from that, unless it does something truly magical, I can't see the point, most people use acrylics as they're 'friendlier' so putting cellulose thinner in them seems to defeat the object, kind of like getting a non alcoholic beer then adding a couple of shots of vodka

[Guest]

I agree Mike, there is little point but I have never been able to get it so transparent. It is great for building up shading

[Guest]

I had trouble with using lacqure thinners and Tamiya dark grey acrylics on my F-15. It dried with a pachy look to it, like some spots were still wet. As soon as I used tamiya thinners, the thing was solved. I didn't have this hassle with the lighter tamiya acrylic. All very confusing, that's why I stick to enamels LOL

While on this subject of thinning, what do you guys use on enamels? I tried to thid blue humbrol with lacqure to get it "transparent" and it seperated the pigments.

Theuns

[Guest]

Very rare I use enamels, in fact, the only enamel paint I use are gloss black in preparation for aAlclad and the other is Humbrol Metalcoat which I have used a couple of times. I have a small bottle of Humbrol Enamel thinners that I use and I guess it will last me at least six months or so due to such limited usage. I suppose that White Spirit would be OK or Turpentine (not sure if they are the same thing) but they are commonly used for cleaning domestic enamel paint from brushes.

[Guest]

I use Humbrol enamels with humbrol thinners, I did try using turpentine substitute once out of curiosity but it didn't do the gloss paint any favours, didn't dry with the typical gloss you'd expect of an enamel.

I'm still not sure why using a cellulose thinner would make the piment transparent other than the fact it flashes off very quickly enabling you to lay down a layer allowing the thinner to quickly evaporate without getting flooding or running?

[Guest]

This my point Mike, I just don't know why either. The whole concept of of the, so called, modulation style is to build up thin layers of semi transparent paint to enable differing depth of colour to represent shade and light. I personally have never had much luck doing this, in fact the Tilly was the nearest I got to getting it nearly right but that is quite crude. It may be a combination of the better control I now have with the .3mm needle in the airbrush but I did notice an immediate difference in laying down layers albeit on card and a pointless test model.

I don't have the answers but I noticed a distinct difference which is why I raised the question. I am looking forward to trying this out on a more serious trial. Just wish I had some time to get stuck in. No modelling again today, to much on. However, had I not had too much on I would have been at Telford so I still wouldn't have got anything done lol

[Guest]

Wheres Ray when you need his input!

Re Telford, it's a shame it's hundreds of miles south, i'd have loved to have gone myself.

[AlanG]

Re Telford, it's a shame it's hundreds of miles south, i'd have loved to have gone myself.

Tell me about it. It takes me roughly just under 5 hours (legally) just to get to the border before i get into England. Can't believe i never went to it when i was based at Cosford.

[Guest]

Not trying to answer all your questions, just remembering some of what I knew way back when I worked for a big paint company.

Acrylics have a closer relationship with cellulose than with oil based paints. Acrylics were developed from cellulose components to move away from the dangerous "fast" solvents.

Not all acrylics are as adaptable!

Having not seen the above DVD I can't comment on what it advises, but would have thought it rather risky using cellulose thinners on plastic models as "fast" thinners tend to attack or melt many plastics.

You may get away with it's use on vinyls and if used very sparingly over other paint, but it is a risky process. Cellulose thinners will most likely react with enamel paints, no matter how old the enamel is.

Using acrylic thinners would always be safer.

[Guest]

I always thin Tamiya acrylics with Isoprop (50/50 mix) - works for me.

[yak face]

I have to agree with terry (spiderman) in being very cautious about using cellulose for thinning paint. As terry says it is very corrosive to most styrene plastics hence why i personally use it as a liquid cement, the only time i have heard it being used is with alclad and then always on top of a primer to give the plastic some protection. I would imagine if an acrylic was thinned with cellulose and sprayed direct on to the bare plastic you would get a reaction and damage to the surface. tony

[Guest]

There are people who swear by using windscreen washer (the blue stuff you put in your car washer bottle) for thinning Tamiya acrylic paints. You just have to make sure it has iso-propanol in it.

[Guest]

mmmm, interesting. Something else i have learnt. Where would you get Isoprop from?

Andy

[Guest]

Andy, its commonly known as rubbing alcohol, i got mine off the interweb, got a gallon for about 20 quid delivered next day, had it a couple of months and hardly touched it yet. I think it comes in different strengths, when i go in the shed later i'll get the company name for you