The Talking Machine Forum — For All Antique Phonographs & Recordings

The first step: Admit you have a problem...

I have rebuilt several pot metal Orthophonic reproducers, of the type that has the needle thumbscrew set at angle, in other words, not going straight into the needle chuck, perpendicular to the reproducer face. In some cases, when a soft tone needle is used, the thumbscrew winds down so far that the edge of the thumbscrew hits the reproducer body. Makes it appear that the thumbscrew head is too large or that the thumbscrew is not long enough. In the photo below, you can see the slim clearance that exists when a loud tone needle is used. When a soft one is inserted however, the clearance disappears and there is interference.

Any explanations? Were these designed perhaps only to use Tungs-Tone needles, with an unchanging shank diameter?

Nobody else has had this happen??

This has happened with a couple of my reproducers, not strictly Orthophonic ones though. I simply don't use the soft-tone needles in these.
Maybe a bit of a point could be ground on the end of the chuck screw, reaching further in to secure the thinner needles?
Bob

I had one Orthophonic sound box where this was an issue. Seems that the needle bar assembly was slightly off-center. When re-positioned on-center between new ball bearings, the thumb screw cap just cleared the housing when a soft-tone needle was inserted.

Just speculation on my part: perhaps the thickness of the shell varied from batch to batch, but the thumbscrews were not lengthened to accommodate them?

OrthoFan

The end of the thumbscrew, from use, has gotten short. TWO FIXES: Order a repro from Ron Sitko, or find an excellent original one that has very little wear.

The end of the thumbscrew, from use, has gotten short. TWO FIXES: Order a repro from Ron Sitko, or find an excellent original one that has very little wear.

By cracky, truer words were never spoken! Immediately after reading this, I switched out the thumbscrew from a soundbox that didn't have this problem into one that did. Instant fix! Wouldn't ordinarily think that a thumbscrew could be worn down like a needle through repeated use, but the wear on the one that wasn't doing its job properly is easily visible to the naked eye. Bonus: the worn thumbscrew works much better in the soundbox it's been switched to -- for now, anyway, and it'll probably be that way for awhile since that machine doesn't get used frequently. Thanks, MicaMonster!

MicaMonster wrote:The end of the thumbscrew, from use, has gotten short. TWO FIXES: Order a repro from Ron Sitko, or find an excellent original one that has very little wear.

Many thanks for solving the mystery!

OrthoFan

MicaMonster wrote:The end of the thumbscrew, from use, has gotten short. TWO FIXES: Order a repro from Ron Sitko, or find an excellent original one that has very little wear.

Of all the things I had considered, that was not one of them. It does make sense though. I'll give it a try. Thanks!!