Using Brass Bushes in Gramophone Motor

[leels1]

Hi, I have a Thorens motor where there is excessive play where the gear shafts sit in the motor casing.

I’ve seen brass bushes for clock mechanisms being used where the shafts have worn where they sit by horologists.

I wondered if anyone has experienced this and if it would work in a gramophone motor given the different speeds vs a clock mechanism. I wondered if it’d excessively wear a brash bush seeing as the gears move a lot faster in a gramophone than a clock.

Any tips would be appreciated! Thank you.

[Inigo]

Eric L Reiss' 'The Compleat Talking Machine' recommends that method. And there is no problem with brass and steel, indeed the governors bearings are brass, and this is the fastest running thing in a Gramophone motor.

[leels1]

Eric L Reiss' 'The Compleat Talking Machine' recommends that method. And there is no problem with brass and steel, indeed the governors bearings are brass, and this is the fastest running thing in a Gramophone motor.

Just shows I should have read his book properly instead of looking at the pictures.

I’ll have to give it a whirl, I don’t remember seeing another machine with all brass pivots ( the HMV 270 I think uses one for the turntable spindle seating. I’ve got nothing to lose so appreciate the comment Inigo.

[JerryVan]

Brass/bronze/steel bushings are very acceptable. The only challenge might be locating the bushing accurately as the worn hole will most likely be oblong, making its original location difficult to determine. If you insert a bushing that aligns with location of the worn area, you will have accomplished little.

[mjbarnes]

Clockmakers have a method for locating the bushing correctly. I seem to recall the bushing needs to move towards the area where the gears exert "pressure". Study up on it before you drill.

[Lah Ca]

An extremely experienced, highly skilled and long-time collector recommended having bearings redone by a clockmaker rather than by a machinist or gramophone-repair expert simply because the clock maker will have stock of pre-fabricated bushings that will need only minor modifications (if any). Things get expensive if you have to pay someone to fabricate a bushing from stock.

[Inigo]

If I remember well, the clue to the right location of the new bearing centre and the discussion about the oblong worn bushing hole is also in that book.