Does the plastic kits are made from age?

[BradG]

As in start to lose some cohesion or integrity after time? I only as as just recently I've had two kits start to crumble when even a small amount of pressure was used to clamp parts. They started to crumble like cheese, clumps started falling off around where it was clamped, it was weird. It wasn't clamped very hard either. I've never had this happen before in a kit. Maybe there was something wrong or a contaminate in the plastic? 

[DeanKB]

24 minutes ago, Jennings Heilig said:

Of course it does. Everything ages (if you buy into the whole linear time myth, that is...).

 

Like most things however, it depends on many factors. The composition of the plastic, the storage conditions, and most importantly, whether it’s been exposed to UV light.

Electrons don't age.

 

Neither do any other elementary particles.

 

And since everything is made from elementary particles, my head is now hurting thinking about it.

[Gerhard]

35 minutes ago, Jennings Heilig said:

Of course it does. Everything ages (if you buy into the whole linear time myth, that is...).

 

Like most things however, it depends on many factors. The composition of the plastic, the storage conditions, and most importantly, whether it’s been exposed to UV light.

Speak for yourself buster!!!! 

[Out2gtcha]

I would say the factors and determining variables are pretty high. But at Jennings said, I think UV Light is probably the biggest killer of plastic besides outright crushing it. The way its breaking down sounds like it may have been bad or contaminated from the jump.

 

What was the kit brand/age/storage conditions?

[DeanKB]

3 minutes ago, Jennings Heilig said:

I don’t buy into the myth of linear time!

You said that tomorrow.

[Out2gtcha]

1 minute ago, DeanKB said:

You said that tomorrow.

 

 

https://www.youtube.com/watch?v=Iir01CbhDls

[blackbetty]

yes, it does, on assembled kits most of the time gearparts fail first, canopys yellow. i have an F-4 kit (revell) from the seventies unassembled, always in box and still the plastic is more brittle than a new kit

[BiggTim]

I agree, most likely a heat or UV light issue.

[ScottsGT]

Even sitting in the box, yes.   Plastics are made of petroleum products. From oil. Over time these different chemicals in the plastic "leach out" or "out gas"  at different rates.  Ever notice that new styrene smell when you first open a new kit?  That's the plastic off gassing.  When enough of the chemical that binds the molecules together off gasses, it gets brittle.

 

In my line of work, installing and maintaining technology in classrooms, one of our biggest issues lately has been the projection screens off gassing.  And the end result is the surface of the screen turning into a gooey mess that you cannot clean up easy.  The screen starts sticking to itself and it makes a nasty mess.  It took days for that crap to wear off my skin where I handled it. 

 

Same goes for that "New Car Smell"  Google it.  It's bad stuff and "experts" warn against breathing this air in the car without rolling down the windows on a new car when getting into it for the first few months.

Edited August 8, 2018 by ScottsGT

[CATCplSlade]

I keep all my models under a black light because I painted them in Day-Glo colors. Now they are all piles of ash.

 

 

 

 

 

 

 

Serious, I am not.

[williamj]

1 hour ago, Jennings Heilig said:

I don’t buy into the myth of linear time!

Then "now" must be arbitrary. or perhaps incongruous.

Edited August 8, 2018 by williamj

[williamj]

I remember a kit..years ago... that peeled,thin sheets coming loose as we worked on it...into the trash bin it went.

   Sad to say Brad this might be the best option for you.from your description the plastic has lost its cohesion.

 

[Gigant]

59 minutes ago, ScottsGT said:

Even sitting in the box, yes.   Plastics are made of petroleum products. From oil. Over time these different chemicals in the plastic "leach out" or "out gas"  at different rates.  Ever notice that new styrene smell when you first open a new kit?  That's the plastic off gassing.  When enough of the chemical that binds the molecules together off gasses, it gets brittle.

 

This is the main reason I don't spring for buying very old model kits, unless I absolutely cannot get it in a more recent release, and still then I don't pay for a higher-priced "collector's special" with a perfect box, etc.

 

The other reason is the decals. I have had too many break into pieces instead of flexing onto the curves, cracks and crevices on a typical scale model's surface.

 

I have seen in recent reviews where Hasegawa's re-issued 1/32 "yellow-wings" kits seem to be very brittle hard plastic, indicating old stock, re-packaged.

[Jack]

One of the most obvious "degrading" qualities in "plastic parts" are the clear parts provided with many vacform models.

I have quite a few of them, and some of these are beginning to "yellow-out" in such a way that it looks like those "clear" parts seen on the real thing parked outside  in museums all over the world were temperatures/sunshine periods are often high....

[Tony T]

2 hours ago, Jennings Heilig said:

I don’t buy into the myth of linear time!

 

Nor do I. It works in brackets and co exists at different speeds. 

 

---***---

 

As for decals, they're just thin layers of ink printed onto water soluble glue paper. They are probably the first thing to go, after any rubber parts exposed to UV.

 

I don't know about the long term compatibility of polyurethane resin, cyanoacrylate glue and styrene plastic, but we all know white metal and CA glue can lead to crystallization so that model weights expand and crack the model they were put in. 

 

It's another reason rigging frightens me. What is its assembled shelf life and how much time is needed for repairs rather than modelling?

 

Tony 

 

 

.

 

 

Edited August 8, 2018 by Tony T
to add ?