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I am thinking about using my Garrard 7a motor to build a gramophone. (and yes, it will have an external horn created from paper).

I noticed that there is a small hole in 'the pan' and wondered if it should have a bung / stopper in it ? (Photograph below).

On the one hand, perhaps the internal oil absorbent pan floor pad, (or 'IOAPFP' for short) when sufficiently 'doused'/ 'wetted', is enough to 'wick' the oil around ?

But surely any excess does not just drip out from the bottom hole onto the internal floor of the gramophone ?

This motor incidentally, is mentioned on Chunny's excellent 'Gramophone Museum' website - link here:

https://gramophonemuseum.com/garrard-columbia.html

So: "To bung, or not to bung, that is the question" .....

Thank every-one as always for any advice you can give.

I hope someone will know, but i'll be surprised if anyone does! Probably an excess oil drain as you say, or possibly pressure relief for heat buildup if that little space is sealed. I remember reading tests of electric motors in The Gramophone where one of their measurements was heat rise over time.

Orchorsol wrote: Thu Nov 16, 2023 4:56 am I hope someone will know, but i'll be surprised if anyone does! Probably an excess oil drain as you say, or possibly pressure relief for heat buildup if that little space is sealed. I remember reading tests of electric motors in The Gramophone where one of their measurements was heat rise over time.

Very interesting 'point' about heat build-up. It does have three springs so it can continue to un-wind for ages.

I agree though, it is probably an excess oil drain.

Fascinating motor. Ingenious design - probably a better design than the Garrard Super Motor I think - showing simpler can be better some-times.

Thanks very much Orchorsol.

Yes, I too think it could be an overflow facility although the position at the bottom is a little strange ? The hole seems to be part of an original design judging by the enlarged photo of the exploded diagram. Your own experiments may well give you the answer to your question ?! An absorbative sheet under the motor would probably be a good idea. A fine motor.

Apologies, seeing "Garrard 7a" I wrongly assumed it was electric (the designation being similar to e.g. Garrard 4a which is an electric motor). I should have seen the spring barrels. Disregard the comment about heat!

emgcr wrote: Thu Nov 16, 2023 6:05 am Yes, I too think it could be an overflow facility although the position at the bottom is a little strange ? The hole seems to be part of an original design judging by the enlarged photo of the exploded diagram. Your own experiments may well give you the answer to your question ?! An absorbative sheet under the motor would probably be a good idea. A fine motor.

Thank you very much emgcr.

Good idea to place an 'absorbative sheet' underneath the motor 'just in case'.

I will soak the original absorbative sheet (which is on the internal floor of the pan) with oil then. This is connected to (and seems to be the same material as) the 'wick'. That must be how it was designed then, I guess. (Photograph of internal pad / wick material below).

Orchorsol wrote: Thu Nov 16, 2023 6:08 am Apologies, seeing "Garrard 7a" I wrongly assumed it was electric (the designation being similar to e.g. Garrard 4a which is an electric motor). I should have seen the spring barrels. Disregard the comment about heat!

ha ha ! Thanks as always Orchorsol.

I am a little bit disappointed though as I had hoped to be able to 'bung up' the hole and fry an egg on the top !

Happy days always !

Here is a selection of Garrard motors advertised by the wholesalers G.A.Bryan Ltd in 1927.
Is it possible that the No.7a was the top of the range precursor to the "Super" ?

epigramophone wrote: Thu Nov 16, 2023 1:40 pm Here is a selection of Garrard motors advertised by the wholesalers G.A.Bryan Ltd in 1927.
Is it possible that the No.7a was the top of the range precursor to the "Super" ?

I would have thought that could well have been the case.

The 7a was of course solely made for Columbia (I believe?) so maybe Garrard decided they had to make something similar and call it 'the Super' for general sales, as they could not sell an exact copy to just anyone ? So 'the super' is arguably not the best but something different enough to prevent Columbia from suing them for breach of contract etc.

Incidentally, I am also pleased that the Model 1a is featured in the information sheet as I consider this to be an excellent motor. My floor standing 'art-deco' gramophone has this motor and I purchased a spare one for it 'just in case'.