The dreaded "zinc pest" attacks MTH P5a Box Cab engine

Wow Eric, when I read the title of your tread I thought it was the wheels you where having a problem with. But, this is the whole die cast body that's falling apart.

I hope MTH can figure out a way to make you whole. Maybe when they do a reissue of the Box Cab they can preorder a few bodies to replace  ones that suffer death like yours. You may have to pay a reasonable price for the body because the engine is almost eight years old, but at lest you will have a the beautiful piece you paid for.

Good Luck, MTH never failed to satisfy me, even when it was my fault. I'm sure they will think of something to help you.

Well ERIC......Thank you for ruining my day(just kidding). I have the same engine and after reading your post I had to look. I went into my climate controlled basement and opened my storage cabinet to find this loco. Took it to the workbench and discovered that the loco is starting to show signs of the pest. Although not as bad as yours, I do realize that in due time this will turn even uglier. The pest is starting around the roof mounted headlights. Anyone else?????

This is(was) my favorite electric. Lets see how MTH steps up to the plate.

The fact that this problem is occuring in modern production in a factory that is far from being brand new and unexperienced is disturbing.  Tells me that quality control is out of MTH's hands and the factory is calling the shots on quality control of thier metal shops.  Not good for us.   Mike

I own an earlier release of the PRR P5a box-cab electric - MTH 20-5510-1 - road number 4777. According to the MTH online catalog it was delivered in August 2000. Has a chrome plated sliding contact on top of pantograph - not black paint as in your photo. Ran downstairs and examined it when I read your post. No evidence of a similar problem. Locomotive has been kept in its own closed glass case for display only - one of my very early locomotive purchases.

MELGAR

WOW!  I'm going to go look at mine!

That just sucks!

chug posted:

I am alarmed and disheartened to discover that the dreaded casting defect often referred to as "zinc pest" has attacked my MTH Premier PRR P5a Box Cab electric engine. I originally purchased this engine in 2009 as part of the beer train set and last ran and handled it about 5 months ago. The engine is one of many on display in my finished dry basement. I am a long time collector of prewar trains too and I am well aware of the early day casting issues. I am an MTH factory trained tech and I know that there were problems with RK Commodore Vanderbilt tenders as well as drivers on RK Hiawatha's. MTH has made good and addressed those problems with replacements. I have contacted MTH and sent them multiple pictures, but the response so far has not been encouraging. I would like to know if anyone else has experienced this same problem, especially with the aforementioned Box Cab engine. Please let me know.

Eric Hofberg

TCA, LCCA 

Hello chug.....

Was there zinc pest like RK NW-2 switchers die-cast frame as mine was made in 1999 ?  Has anyone have that problem ? Its the only RK engine I have and loved that switcher !!!

"I will shout for joy, singing songs of praise to you for saving me" Psalm 71:23

Tiffany

Has this evil ogre from out of the past attacked any other recent production (except the Weaver troop cars)?

Yow!  I shall look closely tomorrow.

I wonder if these Zinc castings were originally Zamak alloy (supposedly 99.99% pure Zinc) or just plain old "pot metal"? Zinc Pest is supposedly caused by lead impurities in the Zinc. In the end the contaminated Zinc part disintegrates from the Zinc Pest. Did MTH make any claims about the alloy of Zinc used for these collector model trains?

What a shame! You guys buy a collector item only to see it disintegrate before your eyes leaving your investment lost. I feel for you guys.

In my world of guns, the German company, GSG, makes Zinc alloy guns (supposedly Zamak) using licensed big gun manufacturers logos like SIG, Colt, and others. The most common is the clone in 22LR of the Colt 1911, the Colt 45 Auto pistol. Are these guns also in for the Zinc Pest if the alloy of Zamak used is at all contaminated? Can you imagine the damage to the shooter if one of these babies disintegrates during firing?  Just how impervious is Zamak to the Zinc Pest? I wonder if GSG made the effort to minimize the contamination of Zamak with lead impurities? I have avoided any Zinc alloy guns knowing Zinc objects did not age well but not knowing the cause or the terminology of Zinc Pest. Along a similar line of thought, what "pest" is hidden in the plastic used in the newest forms of guns? Maybe in a decade or so there will be a Plastic Pest (???).

LDBennett

Someone was cutting corners and recycling the spurs, drips, and other bits that show up from making die-cast. it is not fallowing the week points in the casting, so it is zinc pest(I saw a 700e on here, where everyone was going zinc pest, it was breaking at the weak points in the casting.)

I've got the problem with an early Ps1 GG1, MTH did offer an exchange body but I would have to remove all bits first & pay return postage from the UK ,boy have you seen the postage rates now. Sadly I have turned down their offer & bought a Williams plastic one instead. James

colorado hirailer posted:

Has this evil ogre from out of the past attacked any other recent production (except the Weaver troop cars)?

IIRC there were posts on here a few years back about Atlas O box car parts where some of the trim parts and truck mounting frame pieces that Intermountain had molded in plastic were failing. Could have been done at the same factory?

I hope MTH can figure out a way to make you whole. Maybe when they do a reissue of the Box Cab they can preorder a few bodies to replace  ones that suffer death like yours. You may have to pay a reasonable price for the body because the engine is almost eight years old, but at lest you will have a the beautiful piece you paid for.

I don't mean to single out this comment, but it does bring to mind a couple of questions:

1 - what is the life expectancy of a recent/current production toy/model train?

For comparison, This site says a dishwasher should last approximately 9 years. Mine is thirteen years old and has had some minor repairs. Some parts are already discontinued and have become unavailable. The unit it replaced was far older, and working fine. (It was replaced during a kitchen remodel)

2 - What would a reasonable price for a replacement shell be?

Zinc pest is nothing new. It crops up from time to time. Postwar Lionel transformer control shafts immediately come to mind, and some die cast diesel truck side frames in the 1970's. They are inexpensive parts that I doubt anybody worries about. But shells are likely to be expensive, if they can be had at all.

People collect and even use Lionel trains from before WWI. Have we come so far in our technology since WWII that we can not make toys last a century?

Pot metal things are crap. It is only used because it is easy to cast at low temperatures and easy to machine. Think CEAP. There are other metal thats will last a century like aluminum and especially brass. Zamak is supposed to elevate Zinc casting to a better life but I'm not convinced, even if these pot metal Zinc parts were Zamak (??). I have this Zamak argument with gun people all the time.

LDBennett

Has anyone noticed that the zinc pest shows up more frequently on later Chinese production and is less prevalent on older Korean production pieces?  Manufacturer doesn't seem to matter as much as country of origin.

I had a frame on an 8-10 yr old Chinese made atlas o hopper go bad, and to Atlas's  credit they replaced the whole car.

Plastics fail due to cost cutting and leaving out chemicals which keep the plastic pliable less prone to stress fracturing around screw holes . Bachmann had a rash of plastic failures in its large scale products.... again made in China.

I believe Chinese quality control in the basic materials used to make our RR items is at best poor and time alone will prove this out.

Dave

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 thought the zinc pest only hit speakers in MTH engines? (well, some) I'm gonna check on all my Premier stuff in my collection just to be sure, I don't have this engine like Eric, but I have heard worse stories than this.

In my opinion, there is no safe alloy of zinc and lead that is galvanically stable. Zinc Pest will eventually occur. The solution is to stop making die-cast metal trains. Plastic injection moldings are vastly superior to alloys of zinc and lead. There are multitudes of plastic types / mixtures to choose from.

In my opinion, there is no safe alloy of zinc and lead that is galvanically stable.

According to what I've read, ZAMAC is not supposed to have any more than trace amounts of lead. Somewhere around .005 percent or less.
The major elements of ZAMAC are zinc and aluminum, and there isn't much aluminum at that (3.7 to 4.3 percent).

How many people know that there are different types of ZAMAC?

Those interested in reading more might find the following link to be interesting:  Eastern Alloys

MTH, decent response!  Kind of not surprising.

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

Excellent response, MTH!

Chris

LVHR

C W Burfle posted:

In my opinion, there is no safe alloy of zinc and lead that is galvanically stable.

According to what I've read, ZAMAC is not supposed to have any more than trace amounts of lead. Somewhere around .005 percent or less.
The major elements of ZAMAC are zinc and aluminum, and there isn't much aluminum at that (3.7 to 4.3 percent).

Zinc Aluminum  MAgnesium, and Copper

Not supposed to be any Pb in any of the various zamac alloys as far as I know.

How many people know that there are different types of ZAMAC?

At least 7 types, but probably and very possibly far more could be made varying composition of the 4 components....but I'd expect that the primary useful variations are defined.

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'm glad to read this. In fact it is what I stated MTH would probably do in the first response to this thread.

I'm not waving my flag, but that of MTH!

Someone above said:

"Pot metal things are crap."

This is totally incorrect.

The use of the term "pot metal" is telling.

Let's not make speeches.

===========

Someone else asked:

"1 - what is the life expectancy of a recent/current production toy/model train?"

What a strange question. And you compared it to a washing machine. Even stranger. The life expectancy of any hard good is essentially forever, excluding parts deteriorating from wear and tear (like bearings, wheels, motors, paint), or parts that "rot" (like wood). The bodies on these locomotives should be essentially eternal, in any reasonable sense. My "toy" trains' lifetimes should be almost 100% determined by my treatment and storage of them, not internal "material clocks".

The life expectancy of a properly-made model train should be what I say it is.

MTH seems to have of have had more of this issue than anyone else, though all have had it. I am hoping that my MTH NYC P2 box cabs are OK; I shall go look. I am not dissing MTH; I like their stuff, and mine seems fine, though I have had a few MTH trucks crumble.

I just replaced all the couplers on my 3 car Overton Passenger set.  They literally were falling apart.  The trucks were all OK.  There was one coupler that hadn't fell apart and when I placed a small amount of pressure on it with my fingers, it broke off.  I contacted MTH and they said I would have to buy all new couplers at my expense.  It would have been nice for them to ante up free couplers.  I would simply say beware when buying any items with metal cast parts... you never know what might happen down the road.

The positive response from MTH regarding the issue with the P5a Box Cab and the failing cab casting is exactly what I was hoping to hear. Fingers crossed that MTH is able to find a replacement cab. 

I strongly advise that if you own this same engine with a failing casting, not to be confused with the P5a Improved that resembles a GG-1, to contact MTH and get on the list for a possible cab replacement.

I have in the past experienced casting failure with 3 other manufactures and these were related to freight car trucks, couplers, and it one case the power trucks and side frames on a trolley. I'm happy to report that replacements were provided without charge.  

Thank you MTH

Eric Hofberg

My dad was a metallurgist with one of the major steel companies(Carpenter Steel) in the USA and he used to say that the zinc pest problem shows up when impurities are not removed from the molten metal(liquid metal) before being poured into a mold. Also the mold can be dirty too. Add those both together and you get a very poor casting!!

If MTH will correct the problem at no cost to the consumer that would be great!

Lee Fritz

Let's not get too far afield.

MTH stepped in and is doing the right thing.

HOO -RA!

Bobby Ogage posted:

In my opinion, there is no safe alloy of zinc and lead that is galvanically stable. Zinc Pest will eventually occur. The solution is to stop making die-cast metal trains. Plastic injection moldings are vastly superior to alloys of zinc and lead. There are multitudes of plastic types / mixtures to choose from.

Most illogical argument I have heard in some time, and fundamentally incorrect. Plastics are just as prone to failures, and zinc pest has been a minuscule problem in the history of diecast production. Plastics are less durable, more environmentally troublesome, and far less desired.

Your right Jim. The solution to the Zink Pest issue is better manufacturing controls.

chug posted:

The positive response from MTH regarding the issue with the P5a Box Cab and the failing cab casting is exactly what I was hoping to hear. Fingers crossed that MTH is able to find a replacement cab. 

I strongly advise that if you own this same engine with a failing casting, not to be confused with the P5a Improved that resembles a GG-1, to contact MTH and get on the list for a possible cab replacement.

I have in the past experienced casting failure with 3 other manufactures and these were related to freight car trucks, couplers, and it one case the power trucks and side frames on a trolley. I'm happy to report that replacements were provided without charge.  

Thank you MTH

Eric Hofberg

 

 

Hello Eric.......

Have you checked PAUL G's threaded post just above yours.  MTH told him that he would have to buy the couplers at his expenses.  That is not a "Thank you MTH" at all.  Why should he have to pay for the defective parts when it is not his fault but is the fault of MTH's.  MTH should have done the right thing and that is to replace the couplers at THIER expense not the customer's (Paul G).  I am a Railking fan and I won't accept this way of business.  This is plain wrong.  I checked for my RK switcher's die-cast frame and its ok but when it goes bad, I will go to Ebay to buy spare engine and use the parts from it.  I won't give MTH a penny for parts when they do business like thinking of themselves and not the customer's. This applies to lionel, Atlas and others.   MTH does make GOOD products no doubt about it. So much thank you for MTH !!!!

"I will shout for joy, singing songs of praise to you for saving me." Psalm 71:23 ERV (easy to Read  Version)

Tiffany

Well, mine is the 4777 streamlined version.  No sign of deterioration.

Good die cast really does last a long time.  Model A door handles are still in use.  My ancient Mustang convertibles use die cast fittings on the windshield posts to hold the top on.  Talk about tough duty. Almost all automobiles from the 1940s throuth the1960s used door and window handles of chrome plated zamac.

For what its worth. I restore antique cars. I once had an unobtainable zinc casting part that was falling apart . I coated it with epoxy and it worked . It was a vacuum control manifold and it did its job without leaking.

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.

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. 

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.

I was thinking the same thing. This appears to be a paint problem to me. The underlying shell is not warped and I don't see any bubbles. I have had the dreaded zinc pest and it didn't look like that. I have had a plastic engine and a passenger car that looks the same with some paint issues that looks like the pictures above. A repaint took care of the issue.

Scott Smith

Mine is beginning to exhibit the pestilence, which I'm certain wasn't there when purchased used 2 years ago.  Likely I have no recourse since I'm not the original purchaser.  If there's a chance to purchase a new body from MTH, I could be persuaded to pony up a few bucks.

Bruce

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.