Microphone Screw Threads

I'm not sure if anyone here is familiar with the screw threads used for microphone holders. These are generally either 3/8" x 16tpi or 5/8" x 27 tpi.

Most mike stands have one thread or the other and the actual holders are usually supplied with an adaptor

I bought a cheap microphone stand and a fairly cheap suspension holder.

The stand and its basic holder and the adaptor supplied with the suspension holder appear to be M10 rather than 3/8" as my better quality adaptors won't fit the stand, although the 5/8" threads are fine. Turns out I have enough permutations of adaptor, stand and holder to be able to fit together what I need to but what unnecessary confusion!

Far worse than the loose threads on cameras so you can use 1/4 BSW and 1/4 UNC interchangeably!

Neil

Edited By Neil Wyatt on 30/01/2019 23:42:35

Sir Joseph Whitworth put a lot of research effort into selecting the optimum thread-form for microphone use, and now these Metricating upstarts have wasted it all ...

MichaelG.

Officially, camera/tripod threads have always been UNC. I can get my 3/8th BSW drawbar to hold in an M10 threaded collet by a sufficient number of threads to work but it only happened a few times by accident before I realised the mismatch of threads.

I wonder if your 5/8" one is M16, it may be fine as there is less difference between 16mm and 5/8" than there is between 10mm and 3/8"

Always? I thought UNC only dated from the 1940s.

Brian

I believe the UNC and BSW equivalent sizes in question differ only in thread form (60 degrees versus 55 degree plus differences in roots and crests). Old British photographic equipment was BSW but officially UNC has been adopted and used by manufacturers for decades. Actually I think the standard used now is technically an ISO standard but its based on UNC.

3/8" 16 and 5/8" 27 are the official threads

'I will find an M10 nut and see how it fits on the dodgy '3/8' thread. The '5/8' I have is a bit tight so it could be M15 x 1 but I don't have any M15 x 1 screws lying around to check!

I suspect the cheaper plastic parts are flexible and loose enough not to care, but I prefer to use the better quality parts with metal adaptors and brass thread inserts when they are holding costly microphones!

N.

I believe that UNC and UNF threads are NATO-ised versions of ANC and ANF respectively, the 'U' standing for 'unified'.

The threads on authentic (e.g. Amphenol ) UHF and N-type coaxial connectors were/are 5/8" by 26 tpi ANEF but there are some Far-eastern made connectors on the market with 5/8" by 1 mm pitch threads. Some mate - some don't!!!!

Best regards,

Swarf, Mostly!

Sorry, I quoted AJW but I actually intended to quote Chris Trice.

Best regards,

Swarf, Mostly!