Any chemists out there might know why this happened - I bought a bottle of red food colouring on the way home from work yesterday hoping iI would (cheapskate) be able to simulate red clear colour / tints by adding to Future. I mixed a few drops into the Future but all I got was a disgusting coagulated lumpy mess that turned black!!

The food coloring is probably a alcohol base.

Pete;

Huh.

Sounds like a cool idea - so I took out my "Pledge with FutureShine" (one of the incarnations of Future - and stuff I have used in my recent builds with pretty positive effect mixed with acryls for a satin finish, etc.) and put 1 cc into a mixing cup and added 1 drop of red food coloring... got a great crystal "candy-apple" red out of it. Added 3 more drops and got a deeper clear red. I have poured this mix out onto some kitchen foil to see if it will set and dry as a clear red lens.

My food coloring is the standard el-cheapo stuff we can get at the grocer - the red agent in my color bottle - "FD&C Red 40" - comes mixed with propylene glycol and water.

No gumming or coagulation from this stuff.

IF what you are using is this same chemical compound, it should behave the same.

Here in the USA, "FD&C Red 40" is a US-FDA-Approved synthetic colorant called "allura red AC" - which over by you in the EU has the "E-number" E129 "red shade".

The US-FDA also has approved another synthetic red, "FD&C Red 3", which is "erythrosine", which is known on your end as "E127 pink shade".

Red 40 is a red "azo-dye" or derivative of 2-naphthalenesulfonic acid - a water-soluble compound derived from petroleum (yeah - our FDA apparently approves oil-derived food colorants... ). The other stuff, Red 3, is a very different chemical beast - an organoiodine compound.

I suspect that you guys more commonly get this Red 3 stuff (E127) as your red food color, while we usually get the Red 40 - it's the medico-politics of food. In any case, the Red 3 may well react differently with the ammonia found in the Future than does the Red 40.

Just to "tease" you some more, there are a couple of natural reds used here and over there - and if your coloring contains one of these, well... that's yet another complication in the chemistry!

To put things clear and useful for you (and anyone else looking in on this): Food colors using FD&C Red 40 or E129 will work in Future. Whether any other red colorants will, I cannot say, as I have not tried them!

Hope this helps!

BOB

why dont you jsut buy tamiya clear red it will cost you the same anyway

I have done this with Future and yellow food coloring to make amber lenses. It is a quick and easy solution if you don't have any readily available option.

The issue for those in Europe is that most food colors that we have here in the US are banned for a variety of unhealthy reasons. What is used across the EU is much different than red 40 or yellow 5. A possible solution would be to mix some red watercolor into the Future and see if that gives you the tint you want.

Or even better, I recommend Testors Model Master clear paints; Turn Signal Amber, Stop Light Red, Clear Green, Clear Blue, etc. They will last for ever and are about th esame price as the food coloring and Future. Much easier to work with in my opinion too.

I have used red food colouring and others with Future and other food colourings as well without issue. I use the food colouring from ASDA and TESCO and have not suffered the problem you describe. I have also found that you can enrich the colour obtained by successive dunking.