Strange alteration of model tires (Union 1/24)

[1959scudetto]

In the last months I noticed an interesting phenomenon:

2 Ferrari P 4 models from Union (above, = Heller-reissue, shown here some time ago), both built in the 80’s, show some kind of tire desintegration – the tires are slowly losing their shape (flatspots, partial sidewall deformation) and are “sweating out” an oily liqid.

 

I wiped this off with a paper towel a few weeks ago, but when taking them out of the box today,  I noticed the same again.

Inerestingly, not all tires show this variation.

Has anyone else ever experienced this? Would be interesting to know!

[peteski]

I have seen all sorts of model tire "rot" (one example is what you are seeing).  It depends on the quality and formula of vinyl/rubber (soft plastic) the manufacturer uses for the tires.  I have also seen similar problem in other soft-plastic items (like toys or household items) made in China. Well, most stuff is made in China nowadays. Unfortunately there isn't much that can be done to repair the damage.

The liquid which is leaching out is likely plasticizer (chemical added to make the material soft).  In my experience tires made from real rubber (usually included in Japanese kits like Tamiya, Fujimi, Hasegawa, or Aoshima) are the most durable. They do not leach any liquid, of get squishy, but they can dry out and might crumbly after many years.  That's in the older kits I have.  The tires in some of the more recent kits from some of those companies seem to use a different material  for tires. Not sure if it will also be as durable as the older rubber tires .

[Fat Brian]

Some types of tire materials need plasticizers called Phthalates to be soft. Over time they leech out of the tires and can "burn" any bare plastic that they touch. These chemicals are the cause of "tire burn" in older kits, they transfer to the hard plastic and soften it. If you've ever had a cheep tool with a rubber handle that's always sticky this is why. You can also develop an allergy to these chemicals over repeated exposures.

[Tom Geiger]

I had a similar thing happen in my house.  A towel hook in the bathroom was leaking black ooze down the wall...  My wife had this vision that the entire wall was full of black mold...  but it was similar to the tire issue here.  A plastic / rubber gasket between the metal on the hook and the wall was deteriorating and gravity did it's thing.  It was sticky to the touch and would stain your fingers, but wiped off the wall with lacquer thinner.

[Ace-Garageguy]

All the above.  ^^^

AND...along with BPA (found in many products, as well as canned food liners and plastic water bottles) and certain derivatives of soy, they're testosterone killers (NOTE: The soy data is inconclusive)    https://www.peaktestosterone.com/Phthalates_Testosterone/

There are some extra special folks who refuse to acknowledge it, but average testosterone levels in men of every age are about HALF of what they were 50 years back.     https://myparla.com/decreasing-testosterone-levels/

While the exact causes of the mostly global decline are still somewhat cloudy, there is overwhelming scientific evidence that these things DO have a measurable negative impact.      https://www.vaulthealth.com/blog/articles/Phthalates-BPA-and-testosterone

Don't want to trust my sources? Do your own search.

 

Edited June 6, 2022 by Ace-Garageguy
CLARITY

[Xingu]

Not sure how we went from tire melt to low testosterone, but lets please keep on topic (tires).