Zinc Pest Visits some RMT Hoppers!

I'm continuing my unboxing of stuff to see what I keep and what I sell, also trying to clear some shelves so I can remove them in preparation for my display shelves.  I got to some sealed in factory plastic RMT covered hoppers, and ran into a little problem!

The couplers are crumbling away!  These have been in a climate controlled environment their whole life, that didn't stop them from rotting away!

When I looked closely, the hinges of the knuckle are actually chipped away.

These must have been on their way when they left the factory!

The good news is that the Lionel coupler knuckles, though they didn't look the same when compared to the RMT ones, worked just fine and coupled and uncoupled like they belonged there.

I have to wonder how many more I'll have to replace, all the rest of the cars made it around a few times in a 50+ car train, so the couplers are at least not totally dead.

Interesting, I have at least 3  of the two 2 car sets never opened. I'll check them out to see if I need to go ahead and fix.

Larry

First time that RMT bit me, I've had crumbling couplers from almost all the other brands.

We just thought we have 'over bought' over the years, but we will need all the extras to fix the ones we really like!

I had that on one of my RMT hoppers but since they all just run together in a coal train I JB welded it back together

I thought that type of decay was limited to MTH's Amfleet sets.  I have 2 Metra Amfleet sets that I had to replace all of the couplers right after I bought them.  The guy that sold them to me thought I was making it up.  Even though the were new sets, all of the couplers were shot.  Once I replaced the couplers the sets were perfect.

I think it's come to pretty much all the makers at one time or another.  This was the first time that I saw it on RMT stuff, there isn't that much diecast on the RMT stuff to develop zinc rot!

John has it right. There is not one brand that has proven to be immune to zinc pest. They have all had it somewhere sometime in recent memory. This is the price we are paying for having everything made in China. Their zinc foundry industry has no QC and does not care what goes in the pot, so long as it melts. If companies want to solve the problem, they need take the zinc casting business elsewhere. Of course, the product will cost more, because all the molds stay in China, so new ones will need to be designed and fabricated. Then there is the higher cost of quality raw materials, and the QC that goes into them. Then add in the skilled labor with accompanying higher wage. So pay cheap (a relative term) now and big later (presuming one can even find the parts), or pay big now and little or nothing later.

Rant off.

Chris

LVHR

Does sitting in the box have anything to do with it?

It seems most of these zinc pest threads involve pulling something out of the box.

Has anyone experienced something crumbling on the layout?

High temperatures and humidity are reputed to speed up the process.  However, my stuff was in a fully climate controlled environment it's entire existence, so I doubt that was a significant issue.

I've experienced trucks coming apart while running, but it's hard to know when the damage was actually done.  I know of two JLC GG1's that had their sideframes crumble while on a layout parked on sidings.

Zinc rot is baked into the mix at the time of molding, the only question after that is how fast will it happen.

Rick,

The only thing sitting is the box does is allow the destructive process to continue unobserved. Zinc pest is inherent to the composition of the zinc alloy. High Lead content (we are talking ppm levels) is by far and away the primary culprit. It's in there, you cannot remove it, and you cannot stop the process. That said, certain conditions seem to accelerate the process. Some castings go for years before the damage is evident. Some show in only a year or less. I suspect the higher the lead contamination, the faster the process.

I've had a K-Line coupler and truck assembly disintegrate on the layout. The car was fine for one operating session. The next time I coupled it up, things did not go so well. I've learned to inspect castings for signs of zinc pest. I pull the offender out of service and go looking for replacement  parts. Sometimes I get lucky, sometimes not.

Chris

LVHR

@gunrunnerjohn posted:

First time that RMT bit me, I've had crumbling couplers from almost all the other brands.

We all know that American manufacturers use contract manufacturers in the orient.

I know that the CM's all have their internal go to companies for certain materials.  Example:  I was watching Mr Kim (Kim Bjong Ki, ops manager at Ajin) repair a RoW tender with new decals.  These were just magnificent.  I asked where he got them.  He said:  downtown.  I persisted and got the same answer with a look that said go away.

I tend to believe that there may be a die cast house that specialized in couplers.  I've seen couplers from RoW and 3rd rail that have failed and the syndrome continues.

With that, I can only assume that the CM's over there continue to return to the same internal CM for couplers;  sort of a roll of the dice.

Just my 2c.

Lou N

@Lou N posted:

With that, I can only assume that the CM's over there continue to return to the same internal CM for couplers;  sort of a roll of the dice.

And there's likely no reason for them to do anything about it.  That business probably never sees the repercussions of issues - and my guess is the cost of these items from that supplier is miniscule compared to the markup we pay when we have to replace them.

According to Wikipedia, this was a known problem in the early part of the last century.  But by the 1950's it was primarily resolved.  Clearly it still happens on occasion.  It says some modelers soak their parts in vinegar and then paint them and claim it helps.  How often do couplers or parts crumble away?  Like I said earlier, I've only experienced it once and I've got 100s of cars.  And is there any preventative maintenance like vinegar that would help?

I know of nothing that actually impedes the process, I know of no evidence that suggests vinegar would change the rate of progress.  I suspect those modelers are confusing the white oxide surface corrosion with zinc pest.  Vinegar may clean up the white oxide.

Well, look on the bright side.  We won't have to worry what happens to our trains when we depart this world.  The trains will turn to dust just like us.  I have several AtlasO two bay hoppers that are slowly going that same route

What is interesting is inclusion of lead in such an alloy is illegal in most countries. I know in the US it is illegal to contain any lead without notification of such and completely banned in any product children may use.

I wonder what legal issues this may cause for manufacturers, sellers and distributors?

@Russell - Idaho USA posted:

What is interesting is inclusion of lead in such an alloy is illegal in most countries. I know in the US it is illegal to contain any lead without notification of such and completely banned in any product children may use.

I wonder what legal issues this may cause for manufacturers, sellers and distributors?

Interesting point Russ.

I'd like to hear from the real practicing attorneys and not the arm chair guys what their thoughts are on the subject.

Should be an interesting discussion.

Well stated: Lead is a BIG DEAL in most US industries serving US consumers (especially kids)(do 50+ kids count?), including the one in which I work.  Do we really need an attorney to confirm that? Maybe small traces of lead in zinc would be a  fine point an attorney could use to enlighten us of our right to file a class action suit against our toy train suppliers.  Sorry for being cynical on the subject.   My guess, as an armchair train guy, is there probably is enough lead to turn our trains into dust, but not enough to get our class action lawyers rich.

There's still lead in a lot of things, just in small amounts.  Gosh, many of us use lead solder, that has more lead in it than all your diecast, even if it's all rotting away from zinc pest!   I think the lawyer talk is foolish, nothing's going to happen there, were talking content in PPM, not in real quantity.