K 21 Mercury Cougar

[GHOSTHUNTER]

...and to halt the wheel/tyre degredation, take off the tyres and keep them safe in a paper wrap. With the tyres removed the sticky bubbly stuff around the wheel rim will (eventually!), go back to a state of hardness allowing you to make presentable with a sharp modelling knife.

Only put the tyres back on for taking pictures of the model, leave them on and the reaction starts again, leave them off!

Ghosthunter.

[Brad Pittiful]

so the wheel tire combo makes the cars wheels look like glue is oozing out...dried of course...well i have passed so many red models cheap because of that and its not glue at all huh...i saw this on the white interior model i just received and said...ok its rare i buy this one but the reds ill keep looking

so now that frees up me getting one with the perceived glue oozing out

also i did removed the tires and put the car on the shelf with tires behind the car

[Idris]

so the wheel tire combo makes the cars wheels look like glue is oozing out...dried of course...

I believe that the effect is caused by having a soft plastic (the tyre) in direct contact with a hard plastic (the hub). The soft plastic contains an additive called a plasticiser (which does exactly what the name suggests, acting as a softening agent and allowing the long-chain plastic molecules to move a little with respect to one another, working a bit like oil lubricating moving parts). Since the hard plastic contains little or no plasticiser, some of it will migrate from the tyres to the hubs where it causes the hard plastic to soften and deform ('melt').

[Brad Pittiful]

so the wheel tire combo makes the cars wheels look like glue is oozing out...dried of course...

I believe that the effect is caused by having a soft plastic (the tyre) in direct contact with a hard plastic (the hub). The soft plastic contains an additive called a plasticiser (which does exactly what the name suggests, acting as a softening agent and allowing the long-chain plastic molecules to move a little with respect to one another, working a bit like oil lubricating moving parts). Since the hard plastic contains little or no plasticiser, some of it will migrate from the tyres to the hubs where it causes the hard plastic to soften and deform ('melt').

i see...thanks for the explanation...i have two muiras that the tire/hub are normal...no reaction...i see many k21 cougars with it...is it specific to the cougars?

[GHOSTHUNTER]

Any kingsize model with that particular wheel and tyre combination can be affected. For piece of mind however, I would remove any soft plastic or rubber tyres from any model vehicle (not just matchbox models), with a harder wheel rim.

Ghosthunter.

[Idris]

I have two muiras that the tire/hub are normal...no reaction...i see many k21 cougars with it...is it specific to the cougars?

TBH, I have absolutely no idea! I can only assume that the composition of either the hubs or the tyres on the Miuras is sufficiently different from those on the Cougar for it not to be an issue. It could also be something to do with the time-temperature history of the model in question, include how it's been stored, especially with regards to ventilation. (Are you sure the hubs aren't metal? )

[Brad Pittiful]

I have two muiras that the tire/hub are normal...no reaction...i see many k21 cougars with it...is it specific to the cougars?

TBH, I have absolutely no idea! I can only assume that the composition of either the hubs or the tyres on the Miuras is sufficiently different from those on the Cougar for it not to be an issue. It could also be something to do with the time-temperature history of the model in question, include how it's been stored, especially with regards to ventilation. (Are you sure the hubs aren't metal? )

i just assumed the hubs are like the others...chrome plated plastic

i just checked my easy to access miura and it feels like the hubs are plated plastic not metal...the tires are much harder than the cougars tires...maybe thats the main difference...tire composition is different

[Idris]

If the tyres are harder, then they contain less plasticiser. this might well explain the lack of hub degradation.

[Brad Pittiful]

added the red interior model in the last few weeks...took the tires off as per advice

[GHOSTHUNTER]

A lovely example Brad. Now the tyres are off, the wheel rim 'ooz' will not get any worse as nothing else is in contact with the wheel's plastic except the metal axle which will not be a problem. Over time this 'ooz' will become harder than what it is now and you could if very careful trim off the excess with a modelling knife or a pair of nail clippers to make the wheels look more presentible. It is also tempting to put tyres back on but the choice of tyre regards what the replacement tyre is made of needs consideration.

Tyres of the same consistancy as the rim should be fine, but how to test this is not easy. What I would try is to source another model with the 'oozing' problem and fit some harder plastic tyres similar to those used on the front of the #39 Tractor if they are the same size.

This is not something I have tried, just a mechanical possibilty based on theory.

Ghosthunter.