Mister No's Pics & Vids

Does anybody have any idea why all my old blue Tomica World Road & Rail System and Thomas & Friends Motor Road & Rail engines (Edward, Gordon etc) are suffering from some sort of discolouration of the body of the engine? Wheels are not affected... why?



They are all UK releases (Made in Thailand) and yes, they are at least 15 years old, but I didn't kept them in the sun or something like that; they were in the box. Why then this change of colour occurs? And, strangely, only blue engines are heavy affected, no such change of colour on my other trains... Does anyone else have the same problem maybe? 

The greening of the older Gordon and Edward is a known problem, I see examples like this on eBay fairly regularly. I used to think that it was related to tobacco smoke, having bought a job-lot that included discoloured engines and reeked of smoke, but now I'm not so sure. It could just be that the colour in these old plastics is unstable anyway. But if that's the case, why don't they all go like that?

Yes, we have a couple blue locomotives from that era (notably, Gordon) who’ve turned a green-ish color. Various theories have been advanced in online communities where people collect and restore plastic items like toys, game consoles and old computers. The culprit seems to be bromine compounds added to plastics like ABS and polystyrene that oxidize to a yellow color over time. This will be more obvious on items that are “cool” colors like white and blue.

I’ve never done this myself but supposedly, such items can be restored with a soak in various concoctions that fade the yellow. Oxy Clean, baking soda and hydrogen peroxide have all been mentioned. The downside is that, with repeated use, these treatments will allegedly cause the plastic to become brittle over time.

Although being of the same age, all my old Thomases are, however, not equally affected: 



On the other hand, my Talking Thomases (left) are just fine and not at all discoloured as my Edward & non-talking old Thomas (right):

 
The wheels must have been made of different kind of plastic, since they are not afflicted by the bizzare discolouration:

[Super]

The Great Sodor Mystery, sounds like a new Episode to me.

I was about to reflect that I'd never seen an affected Thomas, but there you are, you've proved me wrong. It does seem though that Gordon suffers from this syndrome much more often. It's all very strange.

I am very disappointed with this too.  It has happened to my Powerful Gordon.

Here we go again!




















And here is the video:

[Super]

Besides your discolored blue trains all of the others are in excellent condition Mr-No. Have you had these since you were a kid?

if you store your precious collection inside a box, the discoloration shouldn't happen.