What is Tamiya XF-21 Flat Base?

Yep, it's an additive for other paints to make them flat. You can add X-21 flat base to Future (about 10-20%) in varying amoungs and create a flat or semi-gloss coat out of it. My experiments showed that going above about 20% resulted in more of a 'cloudy' clear coat rather than a 'flat' clear coat.

M.

Tamiya's Flat Base is, indeed, an additive to make gloss colors flat. I found this out the hard way when the Tamiya paints first came out.

I was about 12-14, somewhere in there, and I built a beautiful Monogram 48th P-47D in far east RAF colors (it was beautiful to a 12-year old, anyway!). I needed to tone down the decals and the gloss I had used under them. I was still brushing paint at this stage and I laid on a nice thick coat of Flat Base over the entire model.

Came back the next day and the whole thing had turned a rather inconsistent white, with some of the paint and markings barely showing thru! You live and you learn, but it gave me an idea which I have yet to try to this day. Perhaps someday in the near future I shall build a Bf 109 in temporary winter camo...

Fade to Black...

Good point naplak .... didn't even pick up on the number. Now I'll have to dig my handy dandy Tamiya colour chart out.

And the survey says XF-21 = sky X-21 = Flat Base

I am not sure if that number is correct tho... XF-21 is a color called Flat Sky.

But that right about the Flat Base...

Just an additive to convert a gloss colour to flat. I'm not 100% sure of the mix ratio though...I've never used it.