Noisy 1958 Hornby Dublo 3-Rail Bristo Castle any ideas

[robmcg]

Hi All,

 

A screeching noise from a 1958 Bristol Castle which we don't know quite how to fix..

 

 

We are wondering if the worm gear is slipping either on the main drive gear below it or on the motor shaft/axle to which its attached, but there's no tightness in motion if we turn the armature manually so no reason for it to slip really.  Maybe the bearings at the ends of the motor shaft/axle are worn out and/or dry?

 

The engine had light to moderate use from new in the 1959-62 era and has been in storage in a dry home since then, often on display on a bookshelf.  Light house dust.

 

Any suggestions most welcome.

 

Cheers

 

 

[Nimbus]

I had a Ringfield 8F do that from new. The theory myself and my Dad came up with was the motor shaft bearings chattering. We never did sort it completely, having tried balancing the armature.

 

The Nim.

[robmcg]

Thanks, the engine was quiet as I remember in in the early 60, possibly age, dried lubricant , corrosion seems unlikely, and with the motor bearings now lightly lubricated.... hmm  The model is not with me but is in my bother's house, where it was filmed.

 

Is a complete strip down the only serious answer? I had rather hoped the noise was characteristic of a particular issue and something-or-other rather specific

 

Cheers

Edited May 31, 2019 by robmcg

[jimwal]

You may have answered your own question!. After sixty years the lubricant will have dried out. As well as the motor bearings lubricate the gears, axle bearings and motion. Do not oil the brushes and commutator. 3 in 1 or cycle oil is fine for these older mechanisms.

 

Jim

[DCB]

Sounds like dry bearings. They have ball bearings at the end of the armature so be careful not to lose them but a good dose of 3 in 1 works wonders.

I would remove the motor and give it a good run without load.   The 1/2  Bristol Castle chassis is better in all respects than the Ring Field.  We have four of each and the Ring Fields give far more trouble, don't start or crawl as well and have no more power. The 1/2" doesn't fill the cab either.

I have a 5 pole armature from a Romford double ended motor in one of my 1/2" motors in an R1 chassis under a Pannier body. Very smooth very gutless, ideal for shunting.

[jimwal]

7 minutes ago, DavidCBroad said:

I have a 5 pole armature from a Romford double ended motor in one of my 1/2" motors in an R1 chassis under a Pannier body. Very smooth very gutless, ideal for shunting.

 

Weak magnet? Many Dublo motors were prone to magnetic loss if dismantled, the ringfields particularly so.

 

 

[PatB]

As suggested, a good clean and oil can work wonders. 

 

If it is chatter in the armature and can't be adjusted out, according to Roger Amos, a simple Darlington pair based controller can reduce noise considerably. Whilst I can't comment on this authoritatively I have just built a verybasic DC motor speed control around a cheap Bd681 Darlington transistor and it has rendered a (admittedly not especially noisy) Hornby 0-6-0 mech practically silent. 

[robmcg]

Thank you all, what a brilliant forum this is.

 

We put a little more lubricant on and especially into the 'top' or rear bearing, and it is now running smoothly.

 

Also cleaned the armature and brushes.

 

Still occasionally makes a very slight noise but the theory is that it just needs a bit of running, and the old track we have requires cleaning and a bit of TLC  to make good electrical joints.

 

Thanks again everyone.

 

here is the oiled and happy Bristol Castle after about 58 years of dis-use...

 

 

Edited June 1, 2019 by robmcg

[Les Bird]

Those old 1/2 HD motors, like the Tri-ang X04 ,if properly lubricated and with clean commutators, will run reliably for years. I have a couple of R1's which can sit in a drawer for ages and will then run perfectly when placed on the track.