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Discussion Starter · #1 ·
I recently acquired a Hornby J94 hoping that it would perform better than the Dapol J94 I already have to the extent that it would not be so noisy due to the gears I think!

I find out however that it has exactly the same motor and gears as the Dapol one; indeed it would seem that the Terrier and LY pugs also suffer from the same problem.

Any thoughts on how to quieten these down?
 

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I had a persistant problem with one of our J94's....it was indeed noisy.....then the gears started to strip.

the problem was the motor pinion started to go out of mesh with the next gear.....eventually free play in the motor caused the gears to part company, stripping the teeth from the axle gear.

this is what is probably happening......plus, excessive end play in the motor shaft causes noise as well.

as it happened, Hornby got sent the remains and had to cure it for good.

run the loco minus bodyshell, and watch the motor pinion/gear relationship.

look for excessive end float at the motor, and possible slight ''lifting' of either the motor shaft, or the motor complete.....at the gear end.....

possibly, excessive vertical axle movement could initiate stripping of the gears too.
 

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They are rather variable, relying on little plastic mouldings secured by self tappers to a larger plastic moulding to clamp the motor in place, any poor alignment or looseness leads to the problems Alastair describes. If it is out of warranty, then strip it down, clean up any flash on the mouldings and reassemble to try and obtain better alignment and firmer motor clamping. I have used Evostick (the old high octane variety not the newly introduced environmentally safe but useless replacement) to assist in holding everything together when tackling a particularly ropey specimen for a friend. The service sheet may help. http://static.hornby.com/files/ss-211e-j94...omotive-296.pdf

Although a fairly crude drive, once it is mechanically sorted it is quiet, and a decent decoder can extract pretty respectable performance.
 

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Discussion Starter · #6 ·
Have quietened my two down at last with a bit of adjustment. Now here is a question. Has anybody tried converting an Austerity 0-6-0 into one of the earlier 48150 class with shorter saddle tank and exposed smokebox?
 

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... Now here is a question. Has anybody tried converting an Austerity 0-6-0 into one of the earlier 48150 class with shorter saddle tank and exposed smokebox?
Answer: 'Saint Johnstoun'!

So what's the 'Jintyesque' variant you have also (I guess) carved out of this model?

I have just one of the Hornby production J94s, now over 15 years since I got it s/h, previous history unknown. Somewhat to my surprise, since 'adjustment' all those years ago it has continued to run smoothly and quietly, and pulls well thanks to a large infusion of lead where once was mazak.The tyres are now thoroughly worn and bright brass, but the brass doesn't corrode or dirt up so pick up is reliable. Pretty good for a cheap purchase, it was half the price of the Lenz Gold decoder inside it, that being the only Lenz decoder available to purchase at the time, 'Silvers' all sold out, and the Standard still some years in the future).
 

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Discussion Starter · #10 · (Edited)
I should add that the pre-austerity variants were rewheeled using Hornby Terrier wheelsets.
The Jintyesque variant is Hunslet 1506 built 1930 for the Pontop & Jarrow Railway. It was really the prototype for the later 48150 and 50550 classes. Hunslets were building Jinties for the LMS at the time and certain features were copied and in the case of 1506 the boiler was very similar. I used a Hornby Jinty body combined with Austerity Cab to create the model. (The cylinders were virtually identical).
Train Vehicle Rolling stock Motor vehicle Building
 

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That's a neat design evolution overview. How to instill confidence in your potential customers. We had experience of the long term proven design used by the largest UK railway business, which most of you will have seen working. We only altered those aspects of the design known to better fit our product to industrial users needs. The advertising practically writes itself.
 

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Discussion Starter · #13 ·
Back to Noisy Hornby. I have a Dapol Terrier which sounds like a circular saw and all attempts to quieten it seem to fail. I've tried shimming the motor mounts and stopping the end float in the motor and with the body off it is much quieter but as soon as you fit the body it is noisy. I wonder if the worm isn't contacting the back of the faceplate on the body and that is magnifying the noise?
 

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Unlikely to be direct contact with a moving part, as you would probably have spotted the 'witness mark' as evidence of the contact, and possibly noticed sluggish performance especially when starting. The hard attachment points of body to mechanism are quite enough for effective conduction; try the loco with the body not screw attached, maybe then try a little rubbery black tack insted of screws for body retention.The underlying problem is that the body is resonant at one or more of the frequencies of vibration from the mechanism; effectively the body is acting as a loudspeaker diaphragm, just what we don't want..

Difficult to further ameliorate too, mass loading in the middle of larger flat panels may help, but the interior is probably short of space to do this...
 

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Discussion Starter · #15 ·
Unlikely to be direct contact with a moving part, as you would probably have spotted the 'witness mark' as evidence of the contact, and possibly noticed sluggish performance especially when starting. The hard attachment points of body to mechanism are quite enough for effective conduction; try the loco with the body not screw attached, maybe then try a little rubbery black tack insted of screws for body retention.The underlying problem is that the body is resonant at one or more of the frequencies of vibration from the mechanism; effectively the body is acting as a loudspeaker diaphragm, just what we don't want..

Difficult to further ameliorate too, mass loading in the middle of larger flat panels may help, but the interior is probably short of space to do this...
I wonder if it would be worthwhile also trying another intermediate gear set for what it is worth in buying one for a few pounds?
 

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I wonder if it would be worthwhile also trying another intermediate gear set for what it is worth in buying one for a few pounds?
Very much your call. There does come a point when there is a risk of moving into 'polishing a turd' territory. I am fairly brutal now given the quality of what is generally available, and have sold almost all my old stuff and replaced with current. (Personally wouldn't hesitate with a Dapol Terrier as it is markedly inaccurate.)
 

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Discussion Starter · #19 · (Edited)
I think Dapol is going to be quietly retired as I don't want to spend any more time on it! I'll see if Col. Holman F. Stephens would like it! (Maybe somebody at the Model Railway Club will take it off my hands!) (Which they did tonight!)
 
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