Garrard Super Motor---Marine type.

[emgcr]

Well, here is a recent fascinating eBay purchase which I have not come across before. It is a standard Garrard Super Motor in concept (later type) but apparently expressly designed for marine use with a bronze or brass case--aluminium is standard---and with supporting legs at the bottom (the top mounts are also threaded in the normal way). It is heavy ! Additionally, the normally tapered drive to the turntable is parallel with keyway and key possibly to accomodate an extended shaft, universal joint etc---but who knows exactly ? The winding handle is also more complex than usual, is articulated and can be folded away.

To date I have only come across two standard types---early and late, the former having external oilways. There is also a Type BB which has a longer drive spindle on the later model.

It has clearly been designed to be securely bolted to a floor or base rather than to be suspended from a deck plate as is more usual. It is one thing to securely independently mount the motor but there are still the considerations of the turntable, tonearm and soundbox to think about. Perhaps the whole set-up could have been gimbal-mounted in some way for boat use ? However, even if that were the case, there would still be no need to separate the motor from the deck-plate ?

Thoughts as to exactly how this might have been used and in what context would be much appreciated.

[Orchorsol]

Fantastic Graham, well done for securing this - I saw it too.

I'm sure I've heard of modified gramophone motors for marine applications, relating to depth sounding - presumably to wind a long line in?

[emgcr]

Many thanks Andy and I had not thought of such an interesting use !

I thought I would experiment with ChatGPT and this is the result which seems to include a certain amount of guesswork ! :

Question :

The Garrard Super Motor Marine Type did not have the usual taper connection to a turntable. Instead it had a parallel-sided shaft with key. What was designed to fit onto this shaft ?

Answer :

ChatGPT said:

The Garrard Super Motor Marine Type featured a parallel-sided shaft with a key rather than the usual taper connection commonly found in standard gramophones. This modification was designed specifically for marine use, where the motor needed to be adaptable to different types of turntables and more robust to handle the specific requirements of marine environments.

On this parallel-sided shaft with a key, a "clutch mechanism" or "marine-type clutch" was typically designed to fit. The clutch would fit onto the keyway and allow for a secure connection to the turntable, enabling the motor to transfer power to the platter while also allowing for easier maintenance or adjustment. The key provided a more secure, non-slip connection that was particularly important for marine applications where vibration and motion could cause issues with traditional tapered connections.
Why the Parallel-Sided Shaft and Key?

Adaptability: The parallel-sided shaft with a key allowed for easier adaptation to various turntables, which might have different designs or require different mounting systems.

Vibration Resistance: The key ensured a more secure and stable connection, reducing the potential for slippage or misalignment, particularly in the rough, vibrating environment of a ship.

Durability: This type of connection also offered better durability and reliability under the harsh conditions found on marine vessels, including exposure to saltwater and constant motion.

Thus, the clutch or other similar component was specifically designed to fit onto the parallel-sided shaft, ensuring a strong, reliable, and adaptable motor connection to the turntable while maintaining smooth operation despite the challenging marine environment.

[emgcr]

I then asked if any photographs or drawings of the clutch arrangement exist ? :

Answer :

The Garrard Super Motor Marine Type featured a parallel-sided shaft with a keyway, differing from the more common taper connection found in other models. This design was intended to accommodate a turntable platter that matched the shaft's parallel profile and incorporated a corresponding keyway. This configuration ensured a secure and precise fit, preventing slippage during operation.​

Unfortunately, specific photographs or detailed drawings of the Garrard Super Motor Marine Type's shaft and its corresponding turntable fitting are scarce in publicly accessible sources. However, for a comprehensive understanding and potential visual references, you might consider consulting specialized resources such as the Gramophone Museum's documentation on Garrard spring motors. This repository offers insights into various Garrard motor designs and may provide relevant information. ​
gramophonemuseum.com

Additionally, reaching out to organizations like Perfect Sound, which specializes in Garrard turntable spare parts, could be beneficial. They might have archival materials or technical drawings that detail the specific components you're interested in. ​
perfectsound.co.uk

Engaging with vintage audio equipment forums and communities can also be a valuable approach. Enthusiasts and collectors often share rare documents, images, and personal experiences that could shed light on the specific design aspects of the Garrard Super Motor Marine Type.

I have to say that, to me, this is all rather unconvincing. Different answers are given to identical questions on successive occasions. However, the idea of a tool instantly able to search the entire internet is certainly a most intriguing notion !

[Orchorsol]

Interesting Graham, and I agree. I suspect the AI has found and expanded on your own original post here, and elaborated idiotically on that and a few other references to produce a seemingly convincing pile of outright garbage. I really fear for humanity and the world. In this context I'm actually glad at 63 years old that my time here on the planet is finite.

[emgcr]

Well said !

Incidentally, I asked the vendor about provenance but he knew no more other than that it had come from the Estate of an engineer.

[JerryVan]

Interesting Graham, and I agree. I suspect the AI has found and expanded on your own original post here, and elaborated idiotically on that and a few other references to produce a seemingly convincing pile of outright garbage. I really fear for humanity and the world. In this context I'm actually glad at 63 years old that my time here on the planet is finite.

Happily, I didn't even bother reading the AI "answer". I refuse to engage with it.