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Metal casting problems at offshore plants is nothing new and not restricted to the model train industry.  When Oneida stainless silverware was made here it was high quality, but the current Chinese made stuff often rusts in the dishwasher.  Marine stainless from overseas can be a very iffy proposition.  Quality control is a huge issue with some of these operations. 

Dominic Mazoch posted:

But even a new shell made of tge same material may not solve the issue.  Maybe it might just be time to look at another material for the shells.

Hello Dominic Mazoch

Yes, I think Brass would be better choice.

"I will shout for joy, singing songs of praise to you for saving me". ERV (easy to read version)

Tiffany

I have heard of a couple of cases and have seen one case where the Lionel Classics that MTH produced for Lionel have had this problem. Not all of those produced have the issue and the incident I saw was the 400E Blue Comet I was thinking about buying.  Seller kept insisting the paint job was going bad and that it wasn't zincpest.  I didn't buy his story or the engine.

Steve

 

colorado hirailer posted:

Zamac on guns? Are we talking barrel, breech, and chamber? I don't wanta be on the range next to that! I have seen an air bubble in a safety that broke off a .22 pistol, and an air bubble in a clutch pivet that broke off on Sat. afternoon on IU game day in Bloomington, lnd.  Luckily there was a guy working late in the closed CHRYSLER dealer and had the part so l got passengers home to another state. Anybody found air bubbles in train castings? Neither of these failures looked like zinc pest.

It is the whole of the lower frame. The slide and barrel/chamber of these 22LR 1911's (and others) clones are steel. There are also some lever action 22's that make the frame out of Zamak with a steel bolt and barrel/chamber. But in all cases the frame has to absorb the forces generated by the cartridge firing. If nothing else, it has to be a durability problem in the making. These guns may work well in their youth but as they age they wear out faster as Zamak is not as wear resistant as steel or even aluminum. It is used because it is a cheap material, easy to cast because of the lower melting point, and easy to machine because it is a soft metal, thus giving those manufacturers a pricing advantage in the market place of sometimes as much 2x.

 

LDBennett

Over the last 20 years we have seen many Chinese made products here in the USA. The common thread through most of them is quality control. That includes the quality of the metals they use for the product. The Chinese manufacturers, like the mainland Chinese people, are excessively driven by profit. I would guess it is not beyond them to buy Zamak and thin it with lead to save a dime. Again and again it has been that mainland Chinese in general have a different view of moral behavior than we do in America when it comes to making money. They don't respect copywrites or patents and have a roaring business in illegal clones of everything. What's a little lead in a Zamak pot to be used for products intended for rich American's train sets?

It seems Lionel and MTH are going to face a serious manufacturing problem if Trump includes a tariff for their trains, (they qualify!). If production has to return to America both will have to start all over again as once the Chinese have the dies and jigs it is said they will never let them leave China. Both Lionel and MTH may have to close up shop permanently or further raise their pricing to include the tariff, making model railroading a rich man's hobby much like vintage car collecting.

Having lived through 70 years of model railroading (much of it from the outside looking it) I see that what we get today is much better performance wise than what we got back in the 1940's and 1950's when I was a kid. Too bad most of the modern stuff may not last for another 70 years.

 

LDBennett

Your argument is non sequitur. As applied to the specifics of diecast models using zinc alloys, corrosion isn't a factor in the long-term usefulness of a casting if the alloy is free, or sufficiently free, of impurities.

All metal alloys are subject to corrosion. The question is how long will it take for a casting to deteriorate to the point it is no longer useful. In the case of Zamac, we still don't know. There are castings now 80 years old that are perfectly intact.

Also, other factors retard corrosion. Painted castings are better than unpainted castings. Storage in controlled environments of low humidity and even temperatures are also a factor.

Most models made from these zinc castings will likely last centuries if properly preserved. As a practical matter, it's clear they will last the lifespan of one or two generations of owners -- more than sufficient to justify their use in toy train manufacturing.

As for your earlier statements about injection-molded plastics, broken pieces that have ended up in the trash far outnumber diecast metal models that have succumbed to zinc pest. The issue isn't corrosion, though chemically plastics do break down over time. The issue is durability. Plastics break. Quite easily in comparison to zinc alloy castings. Therefore less desirable.

Plastics were adopted as a cost-saving measure in the postwar era. They required cheaper tooling, manufacturing process and materials. However, in today's production of toy trains, for which molds are no longer expected to last decades and for which the raw materials used for plastic production have greatly increased, the costs have largely evened out.

Odd-d posted:

Zinc pest can show up in many places.  My dad had a 1955 (I think) Kodak Carousel slide projector.  In 1991 I inherited it.  The whole body disintegrated and I had no choice but to junk it.  Twenty six years later and I still haven't replaced it.  But then I haven't taken color slides since the seventies but viewing those old slides going back to the forties and showing them to my kids and grand kids might be fun. 

Hi Odd-d, look on e-bay and such places, slide projectors are still available for a few bucks. Good luck.

 

Tiffany posted:
Dominic Mazoch posted:

But even a new shell made of tge same material may not solve the issue.  Maybe it might just be time to look at another material for the shells.

Hello Dominic Mazoch

Yes, I think Brass would be better choice.

"I will shout for joy, singing songs of praise to you for saving me". ERV (easy to read version)

Tiffany

First of all casting in brass would cost a fortune. Think about paying three or four thousand for an engine. Building in brass like many manufactures, like 3rd Rail have done is still expensive as compared to di cast.

There is no real substitute for Zinc based di cast engines, the only way at this time to deal with Zink Pest is to insure the production of the alloy and all associated tooling and equipment is done under strict supervision.

That may be true now, but I collect brass and bronze cast model trains, and they were as affordable as die cast in the 1930s and 1940s.  I have converted MTH PA bodies to silicon bronze and nickel silver with some success, and probably own some twenty other O Scale locomotives with brass or bronze cast superstructures.

There is a whole group of collectors who like these things - we call ourselves " doorstop collectors".

Hi Lew, I heard about that. At the time many of the Tin plate products that Lionel and others have built  had di cast wheels and they suffered the same fate. But, as I understand the history, that was the early days of di cast parts and there was a learning curve that most manufactures profited from and thus put bad production techniques behind them.

Today Zink Pest is totally due to sloppy production procedures not ignorance.

As for the MTH issue we are discussing now, if the international trade laws with China where as equable as I was lead to believe from these pages MTH should be able to  sue the subcontractors responsible for this.

I find it hard to comprehend Mike Wolf allowing this to happen knowingly. We may suffer the loss of a favorite toy, but this is his bread and butter.

 

MTH posted:

Just FYI - MTH has been in direct contact with Eric regarding this concern.  MTH will certainly do everything we can to correct the issue he's having. In some cases we have a spare shell. In most others we have to wait to get a replacement until we re-run that engine at which time we will cast extra shells. 

In either case, Eric will be taken care of with regards to his defective shell.

Thank you,

MTH Electric Trains

I have a request,
   There are a couple of us here that because there is no apparent body damage (bubbling) and that the damage looks to be crazing that is uniform across the entire body, think this looks like more of a paint problem. Could you be kind enough to tell us the true finding when the body has been duly scrutinized?

Last edited by Big Jim

There are a couple of us here that because there is no apparent body damage (bubbling) and that the damage looks to be crazing that is uniform across the entire body, think this looks like more of a paint problem. Could you be kind enough to tell us the true finding when the body has been duly scrutinized?

I've been wondering why some folks don't think it's zinc rot.
I guess I'm not certain what the "bubbling" would be.

Last edited by C W Burfle
Big Jim posted:
MTH posted:

Just FYI - MTH has been in direct contact with Eric regarding this concern.  MTH will certainly do everything we can to correct the issue he's having. In some cases we have a spare shell. In most others we have to wait to get a replacement until we re-run that engine at which time we will cast extra shells. 

In either case, Eric will be taken care of with regards to his defective shell.

Thank you,

MTH Electric Trains

I have a request,
   There are a couple of us here that because there is no apparent body damage (bubbling) and that the damage looks to be crazing that is uniform across the entire body, think this looks like more of a paint problem. Could you be kind enough to tell us the true finding when the body has been duly scrutinized?

Good thought, I think the best way to see is to remove the body and take a close look at the inside surface. If Zink Pest is so prevalent on the outside surface if should show signs on the inside as well.

That said, I doubt if this is a paint issue. Failing paint usually blisters up, then peals away not crack like we see. I have never seen paint fail like this unless it's about a hundred years old and is drying out, thus shrinking away from it's self.  

Hi RRMan, that is why I said that this is the fault of the company who made the di cast bodies. This sort of thing could of been forgiven a hundred years ago but not with all people know today.

I think MTH got screwed by folks they trusted to do the job right. Like I said there is absolutely no logical reason  for a manufacture like MTH to do this on purpose.

The dummy that did the work thought they where going to get away with doing a lousy job because they where too lazy to do what was needed, not because there was a ton of money to be saved.  I don't know maybe they will get away with it the way things are today.

But, I know MTH will take care of their customers, they always do.

Who knows what lurks at the bottom of crucibles, or floats on top?  All I know is, paint does not degrade in this fashion, unless it's covering 2 inches of Bondo.  It is definitely zinc pest, identical to numerous other articles produced in Zamac over the last 100 years and suffering the same malady in the initial stages.   It has almost become a regular occurrence and not confined to just our hobby.

Bruce

Last edited by brwebster
rrman posted:

Interesting that in this day of metallurgy, zinc pest would be a well understood phenomena and thus factories can deal with or insure that no impurities contaminate the mixture at casting pour.

Have you ever seen some of the garage type operations that subcontract metal casting in China (and other offshore countries)?  Often it's just a few grimey, unskilled workers in a hovel of a building doing the casting in fairly primitive conditions.  I'm not suggesting the toy train castings are done this hap-harzardly, but nothing would surprise me.  And often it is when only a relatively few castings need to be made that you see this type of operation.  When hundreds of thousands of precise castings are needed, it's profitable to set up a proper facility and maintain quality.  But if only a few hundred castings of a particular body are needed for a run?  And a quality problem that may never show up, at least in only a few units years down the road? 

Zinc (Zamac) casting technology has come a long way. Long lasting parts can be made, but when the casting is done in an environment that uses a base metal with impurities, it will eventually deteriorate and fail. Finding a casting house that uses pure (not scrap) metal is a large problem with offshore casting houses. One of the USA's largest exports to Asia is scrap metal that contains all kinds of things. The scrap is melted down and used again. Quality castings are made from pure aluminum ingots, zinc ingots, copper and iron ore, not scrap metal.

Hm, one way to test, give it a firm pinch, if it is zinc pest it should have some give. Given i see it being handled and not turning to dust, it could just be the paint (or the paint has zinc pest). Paint can dry out if someone fouled up the formula.

The zinc pest would have to be pretty far advanced to be that fragile. When it's in it's earlier stages, I don't think a firm pinch is going to show anything, and the item is not going to fall apart.
I've had lots of rotten wheels that didn't crumble until a fair amount of force was applied.

I don't know why the owner of any item affected by zinc pest would do anything to accelerate the decay until they had replacement parts.

I may of neglected to mention in my original post that in addition to the crazing on the Box Cab body, the sides of the body are starting to bow away from the frame. It is definitely not just paint related. I am including a couple of addition pictures, but it is much more apparent when viewed in person.

Eric Hofberg

TCA, LCCAIMG_5922IMG_5923

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Dennis LaGrua posted:

Zinc (Zamac) casting technology has come a long way. Long lasting parts can be made, but when the casting is done in an environment that uses a base metal with impurities, it will eventually deteriorate and fail. Finding a casting house that uses pure (not scrap) metal is a large problem with offshore casting houses. One of the USA's largest exports to Asia is scrap metal that contains all kinds of things. The scrap is melted down and used again. Quality castings are made from pure aluminum ingots, zinc ingots, copper and iron ore, not scrap metal.

I guess that old saw "You get what you pay for" applies here.   Cheep, cheep, cheep is nothing to Crow about.

I just picture the scenes from "Tracks Ahead" When they go to Cuba and show folks machining and casting parts for the steam trains that they still run there.  In open shacks with primitive ovens and lathes. Shirtless and filthy.  They could be doing good work.   But the odds are against it!   And they also did a show on Chinese steam trains servicing the steel mills there.  A great video I saw on YouTube showing them building Ford cars in China was very eye opening.   They still have guys putting the wheels/tires on the cars by hand.  With impact guns.   One lug at a time.   Just like NASCAR!     Amazing to say the least! 

Jim : )

rrman posted:
Dennis LaGrua posted:

Zinc (Zamac) casting technology has come a long way. Long lasting parts can be made, but when the casting is done in an environment that uses a base metal with impurities, it will eventually deteriorate and fail. Finding a casting house that uses pure (not scrap) metal is a large problem with offshore casting houses. One of the USA's largest exports to Asia is scrap metal that contains all kinds of things. The scrap is melted down and used again. Quality castings are made from pure aluminum ingots, zinc ingots, copper and iron ore, not scrap metal.

I guess that old saw "You get what you pay for" applies here.   Cheep, cheep, cheep is nothing to Crow about.

Last I looked model trains were not cheap!  Its actually a hobby for those with disposable income hopefully not buying disposable trains.

Dennis LaGrua posted:
rrman posted:
Dennis LaGrua posted:

Zinc (Zamac) casting technology has come a long way. Long lasting parts can be made, but when the casting is done in an environment that uses a base metal with impurities, it will eventually deteriorate and fail. Finding a casting house that uses pure (not scrap) metal is a large problem with offshore casting houses. One of the USA's largest exports to Asia is scrap metal that contains all kinds of things. The scrap is melted down and used again. Quality castings are made from pure aluminum ingots, zinc ingots, copper and iron ore, not scrap metal.

I guess that old saw "You get what you pay for" applies here.   Cheep, cheep, cheep is nothing to Crow about.

Last I looked model trains were not cheap!  Its actually a hobby for those with disposable income hopefully not buying disposable trains.

Has to be cheap!   How else could companies fly back and forth to China, have containers of trains made, and ship them around the world, and sell say a boxcar for 22.00??   Or better yet FURNITURE..    How in the world can they build a dresser in China and ship it over here and sell it for half of what one made in America would cost??     CHEAP CHEAP CHEAP! : )

Jim : )

Last edited by carsntrains

Funny you should mention Asian furniture.  Most of that "Asian hardwood" now sold in American furniture stores is actually wood from old rubber trees.  It won't take a penetrating finish so it is sprayed with a coating that replicates a finish, but it will then chip fairly easily revealing raw wood underneath that won't accept a penetrating finish.  And that's why most furniture is now fairly dark colored; it's easier to hide using dark colors; lighter requires more skill.  I apologize for the thread drift.

If I was manufacturing di Cast toy trains, or anything other D-C product for that matter, I would have to seriously consider doing the casting locally where I could keep an eye on the process. Then do the final painting and assembly state side.

By doing it state side you could demand insurance coverage in the contract. I doubt very much if such a contract in China would be worth much of anything, other then the premiums any Chinese assurance company would love to take from you. But, getting paid is another story.

 

Waddy posted:

Funny you should mention Asian furniture.  Most of that "Asian hardwood" now sold in American furniture stores is actually wood from old rubber trees.  It won't take a penetrating finish so it is sprayed with a coating that replicates a finish, but it will then chip fairly easily revealing raw wood underneath that won't accept a penetrating finish.  And that's why most furniture is now fairly dark colored; it's easier to hide using dark colors; lighter requires more skill.  I apologize for the thread drift.

The only way to fix that junk when it fails is to strip the finish down to the wood, laminate wood Viner using a rubber base glue and then putting a real penetrating stain and varnish finish on it.

In other words throw the crap out and build something yourself from scratch. 

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