The Talking Machine Forum — For All Antique Phonographs & Recordings

Hi all

I'm guessing this is a fairly common question, so apologies in advance

I have a question about the types of screw threads used on Edison phonographs.

The screws I'm referring to are mostly the screws used for mounting and attaching the
motors to bedplates etc, as well as other assorted smaller screws (round head & cheese head).

While I believe that it’s desirable for original screws to be used in the restoration of phonographs,
I have noticed with recent purchases I’ve made it’s not always the case. I suppose there are many
reasons, including availability and cost.

Additionally, just trying to source slotted head screws is difficult in itself, given the proliferation of
Phillips head screws (metric in Australia). In fact it’s pretty near impossible in Sydney to buy slotted
head screws in any hardware store.

What sort of thread/s are used on Edison machines? Could I safely say that
as the machines were mostly produced in the US, it would be either UNC or UNF?

Then of course there are the British threads BSW and BSF…

Regards
Ade

Many of the screw threads that you mention used in Edison machines are unusually fine by modern standards. English sizes such as #5-40 (#5 diameter with 40 threads per inch) are common in Edisons. These are still widely available in the USA as are #4-40 and #6-32. But much less available are the fine threads of $4-48, #5-44, and #6-40 that I've seen in Edisons and early Victors. These are nearly impossible to find unless you go to suppliers who specialize in handling a wide variety of screw sizes. I've been able to find the above-mentioned odd threads at McMaster-Carr in the USA, all available as slotted head screws. They also have the matching nuts. Here's their website:

http://www.mcmaster.com

Great, thanks for the info Greg, I'll look at that, and will need
to get savvy with the gauges you've quoted. Once upon
a time I could look at a screw and would have some idea, but
forgotten that now.

For example I could look at a screw and guesstimate it was
say 3/16" (BSW) mild steel slotted round head by ½" long,
but at least now I have something to go on now. Thanks again.

ade

I've read that many screws for Edison machines came from the Waltham Watch Co ....

Thanks Edisone, I’m not surprised having started work on a couple of different machines and
seeing the myriad of ways things are fastened etc. Tiny grub screws for example.

I also did a quick scan on Google and learned a little about the Waltham Watch Co,
and again, I’m not surprised at what you've said, all so emblematic of that great American ingenuity.

Ade

Try this place, they have surprised me a few times
with some of the items they stock:

https://www.boltdepot.com

Chuck

Happy New Year!!!!!

It is ironic that you actually bring this up. I was going to do this topic as well a few days ago.

Two days ago, I went to the local hardware store (ACE) and Home Depot and they now sell these combo slotted and Phillips screw heads, they are not in keeping with the original look. Years ago, I could get machine screws with flat heads.

I also notice the threads seem to be different. I will allow others to discuss this as it seems the new threads do not seem compatible with a lot of the old threads.

I think we are going to have a more difficult time finding flat head screws as we move into the future. So it may be wise to stock up on some common size machine and wood screws for repairs.

Thanks Chuck & Victrola

Happy New Year!!

I’m slowly edging towards some semblance of order in this quest.

With Greg’s info above and Chuck’s link, that will provide a good lead into
sourcing some of the more common screws , which for me seem to be those most frequently required.

I located a good chart on Google the other day that I was going to share and which provided me with some
of the info I was chasing. However, I can’t find it right now, although I just did a quick search and located: http://www.anixtercomponents.com/images ... _chart.pdf

Also, stating up front that I’m a novice at things Edisonia and fully realize that screws and screw threads is
a complete science in itself, particularly when it comes to the purpose of the screw, realizing there may be
applications where the type of steel is also important, but at present I’m more focused on common screws
and identifying exactly what size I need, then ideally being able to source them locally if possible. As Greg says
above, the finer threads are a challenge, and I found this out when I came across a tiny grub screw that needed replacement

Just recently I was in an ALDI store (do you have them in the USA?), it is a serious competitor with the other large supermarket
chains here. I couldn’t believe what I saw, a set of Vernier calipers with digital readout both Imperial and Metric, for $15. These
are ideal for inside and outside measurements and I highly recommend them.

Thanks again for the info.

Ade

If you are looking for correct size screws for a project why not contact one of the shops that specialize in old phonograph parts? These guys seem to have just about everything for a project.

I got a bunch of original stuff from George at Victrola Doctor for my C19.

Heya Joe

I absolutely agree with you, and I can and do support these people, who are often
repositories of huge amounts of helpful information re Phonographs, besides being very decent people.

Although sometimes because I consider I have already reached the limit of my budget for a machine, for
example I purchased a Triumph cabinet from one such person, and the motor and bedplate from another,
then had it shipped to Australia in three boxes (which I can tell you wasn’t peanuts), I had to be sensible.
Also, sometimes if I am in the middle of working on something and need the odd part right away, I don’t
want the hassle of having to wait up to 4-5 weeks for it to ship to Sydney (USPS 1st class is cheapest).

Generally I like to satisfy myself and attempt to solve the problem first, then if I have no luck I will seek the
knowledge. Outside this forum, I don’t like asking merchants for information if I don’t intend to buy from them,
but that’s just me.

Compared to you good folk, we are relatively isolated from the rest of the world, and we don’t have the population
and demand to support many phonograph merchants. There are couple of people I know of in my State, and I have purchased
from them, although they do not have the quantity or variety of parts that are so very readily available in the US, Canada, UK & Europe.

Thanks for the suggestion though Joe, appreciated.

Ade