Trainorama S Class clicking bogie

 
  comtrain Chief Commissioner

Location: Near Albury Wodonga
Ah, a PTC Rod, sort of like a self repairing fuse. I wouldn't use them, they're not that predictable or fast in operation.

It's interesting that the website makes mention of the short circuit current being 2.5A for up to (according to them) 45 seconds. Once the PTC goes open the short circuit it current is reduced to 400mA indefinitely, in the scheme of things that's not a huge current, but it's a lot more than 0.

14 ish volts into a 2.5A load liberates about 35 Watts into something small like a loco wheel for 45 seconds that really could start getting hot, as indeed it seems to have. Beyond the 45 seconds when the PTC has opened you're looking around 5.5 Watts using their 400mA limiting figure.

This is the instance where it will always be my opinion that globes and other work arounds to DCC system shutdowns are bad news. The only safe method to dealing with a short in a 60-75 Watt capable DCC system is to switch the current entirely off. That is, either let the system shut down, or use real electronic circuit breakers that operate near instantly to disconnect the source voltage.
Aaron

Yeah I decided to listen to mate Paul (ex buffer stop) and get rid of them after the melt down.
In fact parcel arrived Tuesday I will cut the globes out and divide the layout up into 15 sections with my DB150's and these NCE devices Smile

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  a6et Minister for Railways

Just going back to Rod's story, with further explanation by Rod, the damage would more likely have been cause by a slightly dirty connection on one wheel trapped between rail on a set of points. The resultant current flowing through the dirty connection would have been enough to heat up the wheel and cause the meltdown.

To answer your question Catchpoint, the owner of TOR did not commit to solving the problem one way or the other. I made him aware of the problem of the poorly meshing gears and he said he would look into it. AFAIK, the meshing problem was not addressed at all, and would therefore still be an issue today. As for providing the replacement muff, I am not sure what issue that was intended to address, as I had not seen any examples of split muff gears.

In defence of TOR, the problem of the poorly meshing gears is not one that I would lay at their door. It was clearly a result of poor design by the Chinese manufacturer, and unless they had good reason to suspect a problem, I would not expect TOR to have dismantled a bogie to look at it, as you would reasonably expect the factory to have got it right. So the most likely passed the sample as being OK for volume production without knowing the problem existed.

Once the problem surfaced, they had a quandary, either ignore it and hope it only occurred in a small number of models, or try and get the factory to admit to a bad design flaw and take the models back. Doing something about it would have created a logistical nightmare, as it is not a simple problem to fix, it virtually requires you to replace the entire bogie with another. I am fairly sure the factory would have tried to reject blame for the problem, leaving TOR to pick up the tab for the fix.
TheBlacksmith

Just a thought came to me regarding this problem & remembering that 3 of our importers used SDK at the time, Austrains & Eureka along with TOR, so far the only diesel types that Eureka has done have been 4 wheel bogie types in the 620 & CPH models, we await the 40cl from SDK & wonder how the gear set up is on that model.

So far, at least from the main reports regarding these issues has centred on the TOR models, with I believe one other person saying at one point they had problems with Austrains models.  So, I have tried to ask around to find out if there has been problems with other ones, namely those from Austrains, overall there is nothing to say that Austrains have had a similar problem so that seems to point the finger purelly at TOR. However as I thought further on this I was able to find out how Austrains may have been able to get a clean sheet.  PLEASE NOTE I said MAY HAVE.

One person I know identified a model from Austrains as having the same issue, but it came from the reject bin that used to adorn every Exhibition, or at least the major ones anyway, where Austrains sold off models that had been returned as being faulty. These models were sold off very cheap, with a notice on the boxes saying faulty, & over the bin a notice that the models had faults, & were offered on sale, as is & with no warranty or returns,

Something that has also been noted with Eureka as well as Auscicion having models on special with faults.  On a trip to one exhibition a few years back where this box was found, one modeller had asked the proprietor what problems were with the models, the answer was "he did not know but had been returned with faults" so they are sold as is"".

I wonder if anyone here has purchased any of those special deals on faulty models & could inform us of the problems.  It may be interesting to know, as to have just one brand out of 3 being the only onr ti have the amount of problems as seems the case a bit unusual.
  TheBlacksmith Chief Commissioner

Location: Ankh Morpork
I can only say that I have an earlier model from Austrains, and I disassembled one bogie from that model and the gears were definitely wider, so would not have had that problem. And it is not the sort of problem that would happen in one model out of a batch and not the next.
  a6et Minister for Railways

I can only say that I have an earlier model from Austrains, and I disassembled one bogie from that model and the gears were definitely wider, so would not have had that problem. And it is not the sort of problem that would happen in one model out of a batch and not the next.
TheBlacksmith

Thanks Geoff, & from memory there was mention from TOR that the problem was confined to one specific run. But the way the replacements look the new factory must be confident the replacements will do the job, at least lets all hope so.
  petan Chief Commissioner

Location: Waiting to see a zebra using a zebra crossing!
Thanks Geoff, & from memory there was mention from TOR that the problem was confined to one specific run. But the way the replacements look the new factory must be confident the replacements will do the job, at least lets all hope so.
a6et

TOR's claim that the problem was confined to one specific run of I presume their 44 class can not be true as my problem TOR 44 class was purchased some years ago yet the S class with the same bogie problem is a very recent production. That suggests the problem is greater than the TOR 44 class and certainly greater than just one small portion of the TOR 44 class. Was the recent replacement material for the TOR 44 class made in the same factory as the recent problem TOR S class?
  TheBlacksmith Chief Commissioner

Location: Ankh Morpork
It must be remembered that the 'replacement' is the gear muff on the axles of the bogies, and this is not the cause of the clicking sound. The clicking comes from gears further back in the chain, see my photo earlier.

So if TOR are offering this as a fix, then they have got it wrong.
  a6et Minister for Railways

TOR's claim that the problem was confined to one specific run of I presume their 44 class can not be true as my problem TOR 44 class was purchased some years ago yet the S class with the same bogie problem is a very recent production. That suggests the problem is greater than the TOR 44 class and certainly greater than just one small portion of the TOR 44 class. Was the recent replacement material for the TOR 44 class made in the same factory as the recent problem TOR S class?
petan

Fair enough, I am not certain which factory the S class was made in, the new or old one.

The GM & those since then are definately from the new one.
  a6et Minister for Railways

It must be remembered that the 'replacement' is the gear muff on the axles of the bogies, and this is not the cause of the clicking sound. The clicking comes from gears further back in the chain, see my photo earlier.

So if TOR are offering this as a fix, then they have got it wrong.
TheBlacksmith

Another interesting aspect in the saga.  Seems that having replacement broken gears may not be good enough, & have those who obtained the replacements still have the clicking sounds, or not?

Is there anyone reading this thread who had the clicking gears issue, & received the TOR replacements fitted them to their models & if so, how are they going, clicking or not?

That is one area where there has been silence even on the 44cl thread so surelly someone must know.
  Roachie Chief Commissioner

Location: Kadina SA (formerly NSW)
I've replaced all six axles in 4 of my 6 locos and have used the "good" axles I removed from those 4 to fix the other 2 locos. All 6 locos are currently running without any problems. Time alone will tell if this continues to be the case.
  a6et Minister for Railways

I've replaced all six axles in 4 of my 6 locos and have used the "good" axles I removed from those 4 to fix the other 2 locos. All 6 locos are currently running without any problems. Time alone will tell if this continues to be the case.
Roachie

So!  Are we to assume that both the clicking sound as well as the splt axles have been fixed with these replacement sets?

How long have you had the defective S cl?  Only reason I ask is, would be good to notify TOR of the problem & hopefully they can replace when the next run arrives.
  allan Chief Commissioner

It must be remembered that the 'replacement' is the gear muff on the axles of the bogies, and this is not the cause of the clicking sound. The clicking comes from gears further back in the chain, see my photo earlier.

So if TOR are offering this as a fix, then they have got it wrong.
TheBlacksmith

In my experience, each "clicking" bogie has had a split muff. The short term fix has been to mechanically isolate the split muff by removing an idler gear. Replacing the split muff will fix this problem.

The problem that you describe is quite different, and can be adressed by shimming the gears to limit the play. Which is not to suggest that wider gears are not a better solution...
  Roachie Chief Commissioner

Location: Kadina SA (formerly NSW)
In my experience, each "clicking" bogie has had a split muff. The short term fix has been to mechanically isolate the split muff by removing an idler gear. Replacing the split muff will fix this problem.

The problem that you describe is quite different, and can be adressed by shimming the gears to limit the play. Which is not to suggest that wider gears are not a better solution...
allan

Allan,

I tend to agree with you, because each of my locos has been running "clickless" since the new wheels/muffs were fitted AND I added the styrene shims to between the outer face of the wheels and the inner face of the bogie side frames. This has ensured that the muff stays properly enmeshed with its neighbouring idler gear, but doesn't address the possible issue of that idler gear and it's neighbour may not be meshing properly......this is a situation I was not aware of until The Blacksmith mentioned it earlier in this thread. In my experience, this has not been a cause of clicking in my locos' bogies.

Roachie
  comtrain Chief Commissioner

Location: Near Albury Wodonga
It must be remembered that the 'replacement' is the gear muff on the axles of the bogies, and this is not the cause of the clicking sound. The clicking comes from gears further back in the chain, see my photo earlier.

So if TOR are offering this as a fix, then they have got it wrong.
TheBlacksmith

Whilst I do agree with your description of the fault in the gear tower, being the cause of the clicking sound, I must say that TOR have indeed fixed a fault. The splitting muff is a fault that needs addressing.

My 930 only starts clicking when it climbs a hill with a load, and that show me the gears are slipping (under stress)
The clicking noise does go away when not under load.Perhaps the gears can float back into mesh?

The S Class with the spit muff has lost traction power and derails when going backwards. The reason is the half axle is no longer providing traction and is wandering in and out of gauge. This loco also has wheel flats which are noisy (less so since I turned each axle a couple cogs to stop all flats hit the rail head together.

Have found some Austrains bogies (removed from an X Class when I replaced the bogies with Trainorama ones) and am going to replace the Austrains side frames with the Trainorama ones and see if they will fit the S Class. But that won't happen till after Liverpool.
Cheers
Rod
  hosk1956 Deputy Commissioner

Location: no where near gunzels
It must be remembered that the 'replacement' is the gear muff on the axles of the bogies, and this is not the cause of the clicking sound. The clicking comes from gears further back in the chain, see my photo earlier.
TheBlacksmith

Not so Blacksmith, I can not agree with you, I recently had a repair evening where 4 930's were repaired, all were clickers, and number of axles were replaced and now none click.
The replacement axles were that, replacement axles, not just the muff.

Wayne
  comtrain Chief Commissioner

Location: Near Albury Wodonga
In my experience, each "clicking" bogie has had a split muff. The short term fix has been to mechanically isolate the split muff by removing an idler gear. Replacing the split muff will fix this problem.

The problem that you describe is quite different, and can be adressed by shimming the gears to limit the play. Which is not to suggest that wider gears are not a better solution...
allan

Ok Allan

I just went out and removed the wheels from my 930 with the clicking sound under load.  All the muffs have been ultrasonic cleaned and the muffs are intact.

On examination, the two idler gears can move about 2mm side to side. Forced over with a screw driver I can see the gears are barely meshing at all. Spinning the motor over shows this idler gear moving back and forwards from full contact to only barely contacting. I believe under load the teeth do start to skip causing the chatter.



As you can see muffs are in good condition and one idler gear has moved almost out of mesh . Before turning it on its side the hidden gear was also out of mesh.  I am fixing the problem by placing a styrene shim between the idler gear and the gear tower wall. Not sure how thick it is, but it does not impede the gear and keeps it in mesh. I cut out a slot wider than the diameter of the pin and will push it in place locking it in position with the side frames when they are replaced. I have made 4 u shaped shims and hope this will fix the gear mesh problem

So now we have a clicking locomotive without split muffs, and
a clicking locomotive with split muffs.

Allan my conclusion is now that your gears are slipping out of mesh, same as mine?



Sorry about focus, but it does show  the idler mesh and the fact that the bronze bushes are barely held by the side plates. The side frames may in fact hold them in place?
Cheers
Rod
  allan Chief Commissioner

The locos with split muffs click all of the time, not just when they are under load, because two of the teeth on the muff are further apart from each other than the remaining teeth. The split runs right through the gear. I think that this problem is a consequence of one stub axle being pressed too far into the muff, into the mould part line.

Looking at your last photo, it appears that the same issue is causing the mis-match of your gears: the bottom stub axles are pressed further into the muff than the top stub axles. Centralise the muff on the stub axles, and your problem will be much reduced, if not eliminated.
  TheBlacksmith Chief Commissioner

Location: Ankh Morpork
I believe the split muffs are caused by the natural shrinkage that occurs in Delrin after it has been moulded. It is not an isolated thing, it occurs quite often with models from other manufacturers. There are countless stories from other countries of 'plastic' gears splitting on shafts. And I have seen the results of many of these splits.

For this reason, I do not use moulded Acetal (Delrin) gears, but ones cut from Acetal stock that has been sitting around for some time and has aged and shrunk a little. I have not had, to the best of my knowledge, any of my gears split.

And I do not place plastic gears of any sort onto a shaft that transmits power, only on idler gears that sit between other brass gears, for the same reason.

If you need to make a gear train, like the axle gears in these models, where the stub axles connect to the muff, then the best way to do it is to not make the axle to muff fit an interference fit, as that will often end up splitting the muff as it shrinks. Rather make the axle slightly smaller and machine longitudinal splines onto the axle, then the splines can engage the muff but allow a minute amount of room for shrinkage.
  TheBlacksmith Chief Commissioner

Location: Ankh Morpork
Looking at your last photo, it appears that the same issue is causing the mis-match of your gears: the bottom stub axles are pressed further into the muff than the top stub axles. Centralise the muff on the stub axles, and your problem will be much reduced, if not eliminated.
allan

Actually, when I examined the bogie, it was the same as in Rod's picture, and the position of the axle gear has nothing to do with the mesh of the intermediate gears. If you look at my original photo, the poor meshing of the gears is with regard to the intermediate gears, not the axle. So centralising the axle gear will have no bearing on that problem.

When examining the bogies of other makers, they use much wider gears, so the problem does not occur with their models.

The loose arrangement you see with regard to the fit of the wheel, bush and muff is there to allow some sideways movement in the axle on sharp curves. But as Rod mentions, at times the bush is barely in contact with the metal power collection cheeks.
  comtrain Chief Commissioner

Location: Near Albury Wodonga
The locos with split muffs click all of the time, not just when they are under load, because two of the teeth on the muff are further apart from each other than the remaining teeth. The split runs right through the gear. I think that this problem is a consequence of one stub axle being pressed too far into the muff, into the mould part line.

Looking at your last photo, it appears that the same issue is causing the mis-match of your gears: the bottom stub axles are pressed further into the muff than the top stub axles. Centralise the muff on the stub axles, and your problem will be much reduced, if not eliminated.
allan

Fair enough, Allan. That is a good call. I got to tell you I need the pictures to see, as my eyes are not that good anymore.
But I will adjust if necessary and see how it goes. The shims are doing the job. Not a click heard since I added them.
But I have to respect the views of a man who manufactures bogies and chassis and sends them all over the World. Without a doubt he has seen it all, whilst developing his own reliable merchandice
Cheers
Rod
  linton78 Train Controller

Location: South Coast NSW
Hi,

I had some spare time this morning so decided to have a look around at muff gears on other models. I found that the Austrains C class muff gear and wheel set slips straight into the 44 class bogie. I am not sure if this is old news? Does Austrains offer spare parts?

For pictures and further reading refer to my blog - http://stonequarrycreek.blogspot.com.au/

While not a fix as such, I would love to compare muff gears from other manufactures, preferably from manufactures that offer spare parts.

Linton
  John_Bushell Chief Commissioner

Location: Brisbane
Just out of interest I Googled "muff" and since the results did not seem all that relevant, I tried "muff gear".  Again a range of interesting results.  Muff coupling seems to be more widely used than muff gear.  From the context though, even though friend Google seems stumped by the term, it seems that the muff gear includes a sleeve through which a shaft passes.

Please correct me if I am drawing an incorrect conclusion.  Not a term I had heard before this issue came up.

For a bit of fun Google muff and muff gear. Laughing

Best regards,
John
  linton78 Train Controller

Location: South Coast NSW
You're right John. A muff coupling is a more common term for a drive shaft type coupling. In my industry I have never come across one with a gear on it though. We do have one on an aircraft ground handler that has a motorcycle type chain around it that links a split muff coupling. If you take the piece of chain off you disconnect the drive train.

Looking for muff on the internet may be fraught with danger ha ha.

Linton
  John_Bushell Chief Commissioner

Location: Brisbane
Looking for muff on the internet may be fraught with danger ha ha.

Linton
linton78

Not so much dangerous as "Not Safe for Work" Linton.
  linton78 Train Controller

Location: South Coast NSW
Not so much dangerous as "Not Safe for Work" Linton.
"John_Bushell"


Ha ha, very true John.

Linton
  comtrain Chief Commissioner

Location: Near Albury Wodonga
You're right John. A muff coupling is a more common term for a drive shaft type coupling. In my industry I have never come across one with a gear on it though. We do have one on an aircraft ground handler that has a motorcycle type chain around it that links a split muff coupling. If you take the piece of chain off you disconnect the drive train.

Looking for muff on the internet may be fraught with danger ha ha.

Linton
linton78

Actually not being a diver, I had not picked up any real meaning to the word in that context. Very Happy
However knowing what the item looked like and did, I had no problem relating to the word. In olden days the girls would rug up and go ice skating. They had a fur covered device attached to the front of their coat into which they would insert their hands up to the elbow to keep them warm. If they fell, they could easily extract their hands to hold themselves off the ice.

Two Austrains wheels are insulated by a plastic device and held in gauge. To me its quite a good description Wink
Cheers
Rod

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