Production of new EMG swan-neck tonearms.

[emgcr]

Many thanks for the kind words which are greatly appreciated. Like other projects, this one has been most enjoyable and satisfying. The more EMG gramophones we have producing top music in this difficult world the happier we are all likely to be !

The tag figures shown in photo No.6 are individual measurements of the achieved offset following initial bending. It is nearly impossible to bend thick-wall tube to a consistent fine accuracy but, after having taken measurements on an assembled EMG base unit, further secondary bending calibration can be made---thus exactly achieving the desired 3 ¾ inch offset. The secondary bending was carried out using a custom built holder held in a vice and with the aid of a simple specially formed tool.

[Garret]

Wow. Just - wow.

Garret

[chunnybh]

I am simply blown away.
Very well done Sir!

[Watanabehi]

The most unobtainable, difficult to make and expensive part of any EMG gramophone has always been the tonearm. I believe
this item has not been manufactured since 1939 and it is thought that the very limited post WW2 production of acoustic gramophones used up pre-war items.

Some years ago I made a batch of Xb aluminium conduits (yet to be polished---see attached photos) most of which have been utilised to bring incomplete base units back into fully operating condition. The surplus is of little use unless matching tonearms can be found to complete the unique EMG technology, thus I resolved to produce a matching number of eleven new swan-neck tonearms. Many of these have now been employed in the completion of machines/instruments and I have a few surplus to immediate requirements.

At the outset of the project I went hunting for the correct encapsulated ball-bearing set and was disappointed to find that it was discontinued and therefore unobtainable. This would not have created an insurmountable problem as new manufacture could have incorporated different internal measurements to allow use of another bearing with slightly different coordinates. However, I then heard of a wonderful firm by the name of “The Vintage Bearing Company” in Burton-on-Trent---email : vintagebearing@aol.com ---which had the correct specification items immediately in stock—hallelujah ! The project has taken over two years and, during this time, I somehow managed to lose this first batch of eleven bearings so had to buy all again ! The problems of getting older……!!

The next part of the investigation was to establish how the original items had been made. A special “X-ray” showed that the main cast brass/bronze arm was produced in two pieces. I wondered if it could be done in one and the very clever foundry---Harling Foundries Ltd, Hastings---email : sue@harlingfoundry.co.uk--- managed to achieve success after a protracted and frustrating period of experimentation resulting in the manufacture of a single traditional wooden pattern. The same brilliant foundry produced the castings for the initial part of the Xb horns some years ago---also a difficult task.

Maintenance of the position of the core and therefore wall-thickness was the main concern, thus the first sand casting was sacrificially drilled in several places to prove requirements. Machining was the next phase which, again, was tricky in view of the awkward shapes involved. Silver-soldered additions of previously machined items could then be made to both ends of the arm. The swinging section of the swan-neck was made and bent in copper tube with brass additions at both ends. It is worth noting that cast brass/bronze was not used for these items so as to allow flexibility of fine-tuning when setting individual “offset” of the finished item---prior to nickel plating. This is absolutely vital for accurate tracking purposes. A jig had to be made to achieve this.

Machining of the bearing housing complete with knurling and threaded section to allow connection to the conduit was relatively straightforward. I am always at pains to avoid plagiarism and have thus stamped my initials and the production number out of eleven which can be seen on the underside of the bearing flange to avoid confusion for posterity---see photo No.5

The final process was carefully to polish all items to obliterate and even-out casting marks thus making ready for polished nickel plating whilst having carefully masked off critical areas where plating is prohibited. Bearings/spigots etc are lubricated with fine grease. The thread for the machine screw retaining the swinging swan-neck section is 4BA.

A final point of note is that EMG improved the swan-neck tonearm over the years, in particular with reference to the joint between the underside of the ball bearing and its mating housing. Originally this was merely a butt-joint and the bearing was secured by a narrow threaded collar but this design did not allow for air-tightness. The final well thought out modification involved a long threaded spigot (seen in photo No.3) which, when lubricated with grease, ensured no escape of air and thus safeguarded/promoted the reproduction of the all-important bass frequencies.

Previous posts have given details of new tonearm rests and tonearm stops of which I still have a few spares. The various nickel-plated collars connecting to the veneered casings can be made to order.

Those are amazing!! If you can sell one on ebay or in other way, I would like to buy one if it is not that expensive. My new project is to make another cabinet like EMG Xb's.

[emgcr]

Email sent.

[Watanabehi]

Email sent.

My email has been changed. The new one is as follows,

hw80035@gmail. com

Thank you.

Hideki

[emgcr]

Email resent.

[VanEpsFan1914]

Theoretically, with enough Meltrope reproducers & such out there second-hand, and enough very good synchronous electric or mechanical motors available--if there was a source of EMG horns, one could start making custom gramophones. I bet that would work fine.

I'm impressed at how much detailed analysis it took to bring back these--the X-ray of the tonearm is just too cool. Thanks.

Charles

[emgcr]

Thank you Charles and you are right ! Unfortunately the world demand for EMG and Expert gramophones is miniscule in relation to the population and production of new machines/instruments is not economically viable. If one could establish actual orders for, say, fifty examples then something could be done but sadly that is never going to happen. The work, and therefore cost, involved is prodigious and one has to remember that EMG/Expert themselves only just managed to make ends meet in the days when gramophones/phonographs were mainstream, popular and sold in huge numbers. Our niche world is very different indeed and new parts are manufactured very much as a labour of love.

[VanEpsFan1914]

I think a market, if there was to be one, would be for a machine about the size of a Victrola Credenza (small apartment-size upright) with a conduit split to hold an EMG horn. A hand-cranked motor would be all right but I think a lot of the big Victor synchronous motors would work--they are plentiful (I have a working one in storage now, from the complete mechanism of a Radio Electrola RE-45) and the Fiberglas horns to prevent drooping would probably do the trick.

Trouble of it is, not as many people can afford to get a hold of something like that. And even when someone can afford it--it's a matter of having space to put it.

Personally I'm impressed that there are any surviving EMG's or even playable 78s; it's amazing just how much of this we have around (compared to, say, paperback books of the same era.)