My Bachmann 37 chassis looks like a banana ....mazak issue ?

[spamcan61]

3 minutes ago, Enterprisingwestern said:

 

why do they use materials they know might be subject to such issues?

 

Mike.

Because they're way cheaper than any alternative and most toy trains are OK most of the time. Agreed they should be more specific about storage conditions if they're going to point the finger.

Edited November 22, 2020 by spamcan61

[rob D2]

16 hours ago, spamcan61 said:

Because they're way cheaper than any alternative and most toy trains are OK most of the time. Agreed they should be more specific about storage conditions if they're going to point the finger.

Well I shot that suggestion straight out the water . As I told Bachmann , in an cupboard in a centrallly heated bedroom was the best I could do short of a strongbox in a bank 

[rob D2]

Here we go ,

wish me luck 

[tractor_37260]

1 hour ago, rob D2 said:

Here we go ,

wish me luck 

It's a fairly straight forward job, sure you'll manage fine ..apart from fixing the small nose circuit/wiring boards on the new frame ends, they are factory melted on, but some CA or epoxy glue will suffice.

Any issues ..be happy to help/advise.....

[rob D2]

There we go then !

 

 

[rob D2]

Question is - I have to reuse this bit - which is the fuel tank weight , with switches.

 

Would that also be “ mazaknotmazak “ ? And if so from The same dodgy Batch ?

Edited November 23, 2020 by rob D2

[Phil Bullock]

A lump of steel Rob? Get a magnet.....

[Roy Langridge]

2 minutes ago, rob D2 said:

Question is - I have to reuse this bit - which is the fuel tank weight , with switches.

 

Would that also be “ mazaknotmazak “ ? And if so from The same dodgy Batch ?

 

I doubt there is any way of knowing what batch of raw material what bits were cast from. Given it is a completely different casting, if I were you, I would just reuse it.

Roy

[Krieghoff]

I have followed this post and the subsequent threads for a while. My Mazak Rot journey began with my Hornby class 31's. All stored in warm well ventilated conditions. The lot of them dropped to bits !

 

Toys or not, it is simply not acceptable for manufacturers to be turning out models like this. I appreciate that there may indeed be QC issues but bring the bloody process in house and manage it. Its not as though manufacturers arent aware of the problem !!

 

I must admit to being very disappointed that Bachmann appear on the face of it to be suffering this blight on some of their locomotives. 

 

I hope and pray that Accurascales 37's are better made and QC monitored closely. I have loads of Baccy class 37's, ive checked them fairly recently and none appear to be suffering from it but then again they were just taken out of their boxes for a quick once over. 

 

Going to check them all again !!

[atom3624]

This is very unfortunate.

 

The 'bad sense of humour' in me was going to ask if Uri Geller had been in the vicinity - that's quite a (typical of rot) warp.

 

MAZAK is almost standard as far as most locomotives are concerned, so the switch mount is likely the same type of material, 'though not necessarily the same batch of metal - hopefully.

 

I hope you're able to resolve the problem satisfactorily - thanks for the eye-opening and interesting thread.

 

Al.

[rob D2]

14 hours ago, Phil Bullock said:

A lump of steel Rob? Get a magnet.....

I checked - it’s not magnetic so I’ll reuse it with care as it seems ok .

 

im reassembling it now - only issue so far is plastic lugs from chassis  plate that fit in block didn’t and one had to be filed , I noticed this was the case with the original as well .

 

 

[Tony Walker]

Got an email yesterday to say my replacement chassis is on it's way too. Will let you know how I get on over the weekend, once I've swapped things over. My replacement is for 254 not 174. I too have to return the duff chassis as well. I did check all my other 37's (all 65 of them). Did spot a small problem with one but the small screw holding the plastic sub chassis on needed to be tightened.

[Roy Langridge]

9 hours ago, Krieghoff said:

I have followed this post and the subsequent threads for a while. My Mazak Rot journey began with my Hornby class 31's. All stored in warm well ventilated conditions. The lot of them dropped to bits !

 

Toys or not, it is simply not acceptable for manufacturers to be turning out models like this. I appreciate that there may indeed be QC issues but bring the bloody process in house and manage it. Its not as though manufacturers arent aware of the problem !!

 

I must admit to being very disappointed that Bachmann appear on the face of it to be suffering this blight on some of their locomotives. 

 

I hope and pray that Accurascales 37's are better made and QC monitored closely. I have loads of Baccy class 37's, ive checked them fairly recently and none appear to be suffering from it but then again they were just taken out of their boxes for a quick once over. 

 

Going to check them all again !!

 

It isn't that straightforward though is it? To bring QA in house, are we saying all raw material has to arrive here in the UK first, be tested and then shipped to China? Not really feasible is it.

As for checking final models, they will look fine when first made, this is a problem that manifests itself over a number of years. Even those making the chassis may not be aware there is an underlying issue as the problem may be several steps back up the supply chain.

 

What we have to accept is that there is a problem but that it is a very very minor one in terms of percentage of models that suffer. So far from over 200+ locos, I have had an issue with one - a Hornby Thomas.

Roy

[spamcan61]

9 hours ago, Krieghoff said:

Toys or not, it is simply not acceptable for manufacturers to be turning out models like this. I appreciate that there may indeed be QC issues but bring the bloody process in house and manage it. Its not as though manufacturers arent aware of the problem !!

 

I agree with your viewpoint but in Bachmann's case it is in house anyway, well Kader's house. Many moons ago now I was specifying a product for manufacture in China, the supplier's own chemical analysis reports I prevailed on them to do showed they weren't using the correct grade  of stainless steel; and this was a 'top tier' ODM, so good luck with quality at source :-/

Edited November 24, 2020 by spamcan61

[adb968008]

2 hours ago, Roy Langridge said:

 

What we have to accept is that there is a problem but that it is a very very minor one in terms of percentage of models that suffer. So far from over 200+ locos, I have had an issue with one - a Hornby Thomas.

Luckier than I, from quick memory ive had :

 

2x 92221, 2x 31, 2x 50, 1x47, 75070, 35005, a Liliput BR 52, 1x Maunsell 2-6-0, a Bachmann QJ (that really hurt the wallet). Right now Ive a T9 which I replaced the motor housing 3 years ago, which last week I found the motor retaining plate has now corroded.

Of that lot most have been repaired, the BR52 was despatched, the Chinese QJ just hurts my soul hoping someday I can get a new chassis for it.

 

Admittedly I have considerably more than 200 locos, so the ratio is possibly similar.

Ive too many 37’s but it may prove worthwhile for me to check and start divesting if theres any risk, especially as both prices are high right now, and a challenger is on the horizon.

 

 

 

Edited November 24, 2020 by adb968008

[Pacific231G]

On 22/11/2020 at 12:11, rob D2 said:

 

I didn’t realise mazak was like the word hoover , not a generic term 

The second entry here covers it

https://en.wikipedia.org/wiki/Zamak

and it looks as if Mazak is an outdated term in general engineering usage.

It's worth remembering that Zamak was developed spcifically to avoid zinc pest. It just seems that some batches fail to achieve that aim.

There's a very thorough run down of Zinc alloys here and I hope this lot aren't experiencing zinc pest. 

https://www.nuclear-power.net/nuclear-engineering/metals-what-are-metals/alloys-composition-properties-of-metal-alloys/zinc-alloys/

As an aside I hadn't realised that nickel siver was an alloy with zinc, (usually 60% copper, 20% nickel and 20% zinc) and 

I suspect that our hobby uses a wider range of metal alloys in engineering situations than do most.  

 

 

[rob D2]

It’s finished and it runs , just need to sort out the slightly chaotic wiring .

 

took about 2 1/2 hrs to do ,

[Markwj]

Got my grain flow 37068 out of the attic and took it apart. Chassis block looks ok apart from this bit. Unsure if a symptom of rot or not. Model has been stored in the attic with the usual variance of temperature.

 

[adb968008]

13 hours ago, Markwj said:

Got my grain flow 37068 out of the attic and took it apart. Chassis block looks ok apart from this bit. Unsure if a symptom of rot or not. Model has been stored in the attic with the usual variance of temperature.

 

Looks more like a bad finish to the casting, than the cracking of mazak.

 

You could always try putting a screw driver to it, and tapping gently with a hammer.. a scratch is ok, if it starts disintegrating then you know.. just ensure you tap at a point where theres no window, so the scratch is hidden.

 

 

[tomparryharry]

Regarding the finish, I agree. Molten metal sometimes creates a 'skin' where the molten metal meets atmosphere.  It's known as 'dross'.  The effect you're seeing can be caused by such things as dirty metal,  (inclusions) , metal too hot (shrinkage ) and the alloy itself being not quite right in its constituent parts.  The list is not exhaustive, so its down to the person doing the casting to get it right. 

 

I notice that the casting is painted. I wonder why?  In production terms, it's an 'added' job, and doesn't necessarily add value. After all, that's what the body is for...  A manufacturer will 'tweak' a casting to improve the look. "A coat of paint hides a multitude of sins"...  Remember though, that these are 'just toys' and made with whatever material  the contractor can reasonably  get away with. I'd guess that Bachmann could insist a known-value material standard, but be prepared to see the final cost going through the roof. 

 

Cheers,

Ian. 

[phil-b259]

10 minutes ago, tomparryharry said:

 

I notice that the casting is painted. I wonder why?  In production terms, it's an 'added' job, and doesn't necessarily add value.

 

 

Because it is visible through bodyside windows and a silver lump is far more noticeable than a matt black one.

[rob D2]

I agree , I don’t think the metal is an issue there .

 

my first sign was the chassis block getting an actual bend and distorting the plastic sub assembly - if Both the block and plastic bit are straight on the bottom edge you should be ok so far .

Edited December 15, 2020 by rob D2
iPad is forest gump

[tomparryharry]

1 minute ago, phil-b259 said:

 

Because it is visible through bodyside windows and a silver lump is far more noticeable than a matt black one.

 

Thanks, I didn't know that.

[JSpencer]

On 24/11/2020 at 00:06, Krieghoff said:

I hope and pray that Accurascales 37's are better made and QC monitored closely. I have loads of Baccy class 37's, ive checked them fairly recently and none appear to be suffering from it but then again they were just taken out of their boxes for a quick once over. 

 

 

Accurascale will be using a tungsten chassis block. No risk of mazak rot there. Just a risk of breaking your foot if you drop it.

[No Decorum]

On 15/12/2020 at 20:34, JSpencer said:

 

Accurascale will be using a tungsten chassis block. No risk of mazak rot there. Just a risk of breaking your foot if you drop it.

Sadly, no.

https://www.rmweb.co.uk/community/index.php?/topic/149301-class-37-by-accurascale/&do=findComment&comment=3738042