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Re: Mystery Deepens-- Gutta Percha Stylus bar.. Help!

Posted: Wed Apr 11, 2018 6:54 am
by Fonotone
I have the same stylus bar, Brad. But my gp reproducer has a metal diaphragm, possibly a Mobley. The link appears to be attached to the surface of the diaphragm with a dot of solder, or possibly it's just ancient resin -- it's difficult to tell (see pics). In any event, if the diaphragm is a Mobley mod, then perhaps the stylus bar is too?

-- Grant

Re: Mystery Deepens-- Gutta Percha Stylus bar.. Help!

Posted: Wed Apr 11, 2018 9:28 am
by outune
Thanks Grant--- Mobley Mod ? That would be interesting-- In your pic, it appears that the bar is touching the diaphragm in a few places.. Is that just the angle of the picture? Touching would kill the vibration.

Another member posted that his GP has the same stepped bar that "simply slots into a horizontal pin on the stud attached to the diaphragm." I'm hoping that he will be able to post a picture of his soon to add to the information.

Thanks for posting the picture, Grant. Hope all is well.

Brad

Re: Mystery Deepens-- Gutta Percha Stylus bar.. Help!

Posted: Wed Apr 11, 2018 10:08 am
by Fonotone
Yeah, it looks like a Mobley diaphragm, Brad. Tinted pink/purple like a Mobley too. There's virtually no daylight between the stylus bar and the diaphragm, but (surprisingly) the reproducer sounds okay (certainly for a gutta percha model).

-- Grant

Re: Mystery Deepens-- Gutta Percha Stylus bar.. Help!

Posted: Thu Apr 12, 2018 8:44 pm
by Shawn
Brad,

Here is a picture of an original, unaltered one. This came on my 1894 Bell Tainter G. As you can see, it has a bell-shaped housing similar to later reproducers.
IMG_20180412_184059800.jpg
I believe I can even tell you why the needle bar is formed differently than on later reproducers. On the Bell Tainter, the reproducer hangs upside down and rests against the mandrel when not in use. This bend in the bar allows the top of the reproducer to rest on the mandrel, rather than so directly on the sapphire.
IMG_20180412_203833130.jpg
Shawn

Re: Mystery Deepens-- Gutta Percha Stylus bar.. Help!

Posted: Thu Apr 12, 2018 9:03 pm
by JerryVan
I think somebody said that on April 7. :roll:

Re: Mystery Deepens-- Gutta Percha Stylus bar.. Help!

Posted: Fri Apr 13, 2018 8:10 am
by outune
Thanks Shawn and Jerry---

Jerry- You're a prophet-- Your 4/7 post was an educated "guess" that has now been verified by Shawn's picture. Trust, but verify.....seems I've heard that somewhere before!

The "bell" looks to be more substantial than the typical Columbia floating. Shawn-- Is the "bell" a solid steel piece or hollow?

Thanks so much to everyone who has helped figure this out... And Grant's potential Mobley adaptation ads a little color to the discussion!

I truly appreciate all the help.

Brad

Re: Mystery Deepens-- Gutta Percha Stylus bar.. Help!

Posted: Fri Apr 13, 2018 10:36 am
by JerryVan
outune wrote:Thanks Shawn and Jerry---

Jerry- You're a prophet-- Your 4/7 post was an educated "guess" that has now been verified by Shawn's picture. Trust, but verify.....seems I've heard that somewhere before!

The "bell" looks to be more substantial than the typical Columbia floating. Shawn-- Is the "bell" a solid steel piece or hollow?

Thanks so much to everyone who has helped figure this out... And Grant's potential Mobley adaptation ads a little color to the discussion!

I truly appreciate all the help.

Brad
Brad,

Yup, you caught me, it was a guess. :)

Re: Mystery Deepens-- Gutta Percha Stylus bar.. Help!

Posted: Fri Apr 13, 2018 2:02 pm
by clevelander
Outune,
I have uploaded some photos from my daughters camera which, unfortunately is not very high resolution.
I see I have been pipped to the post. :oops:
Regards,
Alistair.

Re: Mystery Deepens-- Gutta Percha Stylus bar.. Help!

Posted: Fri Apr 13, 2018 5:56 pm
by Shawn
Hey Brad,

I've compared it with several of my Aluminum Eagle reproducers. I am pretty confident they are the same as the one on the Gutta Percha. I tried to mic it, and as best I could tell, its the same.

It is a solid piece, spun, with a slot down the middle and a pin.

Glad we could all help. That's why I love this community.

Shawn

Re: Mystery SOLVED-- Gutta Percha Stylus bar.. Help!

Posted: Sun Apr 15, 2018 11:20 am
by outune
Shawn, Alistair, Jerry and everyone else- THANK YOU!!!!!! Mystery is officially solved. I think Shawn's suggestion as to why this type needle bar was produced make perfect sense.

I truly appreciate all the great help!!

Brad Abell