Re: [Phono-L] Credenza speed readout needle chatter

2019-09-14 Thread Ron L'Herault via Phono-L
George Vollema at Great Lakes Antique Phonographs is excellent.   I work on
them too, but am a hobbiest.  I’m in MA but near Providence RI.

 

Ron L

 

From: Phono-L [mailto:phono-l-boun...@oldcrank.org] On Behalf Of Robert
Wright via Phono-L
Sent: Saturday, September 14, 2019 11:10 AM
To: Antique Phonograph List
Cc: Robert Wright
Subject: Re: [Phono-L] Credenza speed readout needle chatter

 

Well, after another round of removing and cleaning the indicator mech, and
putting a longer pad (which didn't help at all) and adjusting this and that,
I decided to just leave the damned thing off for a while so I could simply
enjoy my phonograph for a few days…

 

And the noise is still there. The clacking component of the sound, it turns
out, was actually the governor "arm" that gets lowered by the speed
adjustment screw on top, at the point of contact between them. So at this
point, it's a governor problem, evidently.

 

Is there anyone on this list I can send this motor for repair/adjustment? I
simply don't have the time nor the skills to take it all apart and get it
right, but I do have money. I'm all about learning to fix these machines and
have done lots of work on them, but I need some expert help on this one. I
just don't have it in me. Anyone?

 

 

Thanks,

Robert

 

 

On Sep 13, 2019, at 6:22 PM, SN Medved via Phono-L 
wrote:





WD-40 is not a lubricant.  It works good as a cleaner or to displace water,
but not as a lubricant.  Liquid Bearings works well and has no smell and is
synthetic.  

 

Steve

 

  _  

From: Phono-L  on behalf of Robert Wright via
Phono-L 
Sent: Friday, September 13, 2019 12:34 PM
To: Antique Phonograph List 
Cc: Robert Wright 
Subject: Re: [Phono-L] Credenza speed readout needle chatter 

 

Firstly, thank you both for the detailed info!  

 

Ron, it looks like your suggestions are aimed at reducing vibration from the
governor mech itself, the application of which makes perfect sense. I just
may try that on all the motors here, in fact. Thank you!

 

Andrew, it sounds like you're suggesting that once the indicator arbor is in
(let's call it) 78rpm position, it is in that specific axis (or axes) where
the hole may have become enlarged and/or the arbor's pivot post has become
polished -- i.e., there's no chatter at other speeds because the indicator
pad is in a different position, placing the posts where the wear has not
occurred. This makes perfect sense to me, especially as the indicator
chatter happens with at least one other motor here (a spring one, not the
electric one I initially wrote about). I'm sure both machines have operated
at 78rpm or thereabouts their entire lives, indeed.

 

It also makes sense that adding grease to the pad helps, but only for a few
plays -- once it has cleared out of the path, the posts are again in (let's
call it) chatter position.

 

In that light, would you think installing a significantly longer leather pad
into the arbor would change its rotational position enough to place it into
a "fresh" spot? It would also increase the return spring tension slightly,
which may help alleviate chatter. Doesn't seem like it would take much,
perhaps an additional 16th - 8th of an inch. It might get another 100 years
of chatter-free use if so. Thoughts? (I've also used a spritz of WD-40 to
lubricate the post holes -- perhaps I'll slather a fingertip of grease on
them instead.)

 

I also considered sympathetic resonance, but I don't know how much the math
lines up, considering it is a range of speeds (albeit a narrow one) while
the 60Hz vibration is more or less constant (I realize the 60Hz vibration
and any errant governor vibration are two different things). But the hole
wear, in my mind, lines up to that problem range quite well!

 

I say it often in my emails here, but it bears repeating once again: to
someone like me who loves phonographs much more than they have technically
studied them, this list isn't just a handy resource, it's a lifeline. Thank
you, gentlemen.

 

 

Reporting back soon,

Robert

 

 

PS - In my defense, I never said the source of the chatter was the point of
contact between the pad and the flywheel! I only meant to describe the
symptom, i.e., where the noise occurred, not the underlying disease that
might suggest a cure. I just get in a hurry sometimes. I'll try to be
clearer! :-)

 

 

 

 

 

 

 

On Sep 12, 2019, at 3:30 PM, Andrew Baron via Phono-L 
wrote:





Hi Robert. Intriguing problem, and I think I may be able to shed a little
light. My supposition could be wrong, but if you look at the physics of the
thing, it could point to not one issue (“…obviously the contact point
between the leather nib…”), but more likely two issues. You have to raise
your perception above where the symptom’s cause would appear to originate,
and look at the whole picture.  

 

The key to solving your mystery may be directly related to something you
conveyed very precisely, that the issue occurs over

Re: [Phono-L] Credenza speed readout needle chatter

2019-09-14 Thread Robert Wright via Phono-L
Well, after another round of removing and cleaning the indicator mech, and 
putting a longer pad (which didn't help at all) and adjusting this and that, I 
decided to just leave the damned thing off for a while so I could simply enjoy 
my phonograph for a few days…

And the noise is still there. The clacking component of the sound, it turns 
out, was actually the governor "arm" that gets lowered by the speed adjustment 
screw on top, at the point of contact between them. So at this point, it's a 
governor problem, evidently.

Is there anyone on this list I can send this motor for repair/adjustment? I 
simply don't have the time nor the skills to take it all apart and get it 
right, but I do have money. I'm all about learning to fix these machines and 
have done lots of work on them, but I need some expert help on this one. I just 
don't have it in me. Anyone?


Thanks,
Robert


On Sep 13, 2019, at 6:22 PM, SN Medved via Phono-L 
mailto:phono-l@oldcrank.org>> wrote:

WD-40 is not a lubricant.  It works good as a cleaner or to displace water, but 
not as a lubricant.  Liquid Bearings works well and has no smell and is 
synthetic.

Steve


From: Phono-L 
mailto:phono-l-boun...@oldcrank.org>> on behalf 
of Robert Wright via Phono-L mailto:phono-l@oldcrank.org>>
Sent: Friday, September 13, 2019 12:34 PM
To: Antique Phonograph List mailto:phono-l@oldcrank.org>>
Cc: Robert Wright mailto:esrobe...@hotmail.com>>
Subject: Re: [Phono-L] Credenza speed readout needle chatter

Firstly, thank you both for the detailed info!

Ron, it looks like your suggestions are aimed at reducing vibration from the 
governor mech itself, the application of which makes perfect sense. I just may 
try that on all the motors here, in fact. Thank you!

Andrew, it sounds like you're suggesting that once the indicator arbor is in 
(let's call it) 78rpm position, it is in that specific axis (or axes) where the 
hole may have become enlarged and/or the arbor's pivot post has become polished 
-- i.e., there's no chatter at other speeds because the indicator pad is in a 
different position, placing the posts where the wear has not occurred. This 
makes perfect sense to me, especially as the indicator chatter happens with at 
least one other motor here (a spring one, not the electric one I initially 
wrote about). I'm sure both machines have operated at 78rpm or thereabouts 
their entire lives, indeed.

It also makes sense that adding grease to the pad helps, but only for a few 
plays -- once it has cleared out of the path, the posts are again in (let's 
call it) chatter position.

In that light, would you think installing a significantly longer leather pad 
into the arbor would change its rotational position enough to place it into a 
"fresh" spot? It would also increase the return spring tension slightly, which 
may help alleviate chatter. Doesn't seem like it would take much, perhaps an 
additional 16th - 8th of an inch. It might get another 100 years of 
chatter-free use if so. Thoughts? (I've also used a spritz of WD-40 to 
lubricate the post holes -- perhaps I'll slather a fingertip of grease on them 
instead.)

I also considered sympathetic resonance, but I don't know how much the math 
lines up, considering it is a range of speeds (albeit a narrow one) while the 
60Hz vibration is more or less constant (I realize the 60Hz vibration and any 
errant governor vibration are two different things). But the hole wear, in my 
mind, lines up to that problem range quite well!

I say it often in my emails here, but it bears repeating once again: to someone 
like me who loves phonographs much more than they have technically studied 
them, this list isn't just a handy resource, it's a lifeline. Thank you, 
gentlemen.


Reporting back soon,
Robert


PS - In my defense, I never said the source of the chatter was the point of 
contact between the pad and the flywheel! I only meant to describe the symptom, 
i.e., where the noise occurred, not the underlying disease that might suggest a 
cure. I just get in a hurry sometimes. I'll try to be clearer! :-)







On Sep 12, 2019, at 3:30 PM, Andrew Baron via Phono-L 
mailto:phono-l@oldcrank.org>> wrote:

Hi Robert. Intriguing problem, and I think I may be able to shed a little 
light. My supposition could be wrong, but if you look at the physics of the 
thing, it could point to not one issue (“…obviously the contact point between 
the leather nib…”), but more likely two issues. You have to raise your 
perception above where the symptom’s cause would appear to originate, and look 
at the whole picture.

The key to solving your mystery may be directly related to something you 
conveyed very precisely, that the issue occurs over an extremely narrow band of 
speeds. So, it appears that we have a primary cause (vibration source at the 
leather and flywheel), exacerbated or amplified by a secondary condition, which 
I will a

Re: [Phono-L] Credenza speed readout needle chatter

2019-09-13 Thread SN Medved via Phono-L
WD-40 is not a lubricant.  It works good as a cleaner or to displace water, but 
not as a lubricant.  Liquid Bearings works well and has no smell and is 
synthetic.

Steve


From: Phono-L  on behalf of Robert Wright via 
Phono-L 
Sent: Friday, September 13, 2019 12:34 PM
To: Antique Phonograph List 
Cc: Robert Wright 
Subject: Re: [Phono-L] Credenza speed readout needle chatter

Firstly, thank you both for the detailed info!

Ron, it looks like your suggestions are aimed at reducing vibration from the 
governor mech itself, the application of which makes perfect sense. I just may 
try that on all the motors here, in fact. Thank you!

Andrew, it sounds like you're suggesting that once the indicator arbor is in 
(let's call it) 78rpm position, it is in that specific axis (or axes) where the 
hole may have become enlarged and/or the arbor's pivot post has become polished 
-- i.e., there's no chatter at other speeds because the indicator pad is in a 
different position, placing the posts where the wear has not occurred. This 
makes perfect sense to me, especially as the indicator chatter happens with at 
least one other motor here (a spring one, not the electric one I initially 
wrote about). I'm sure both machines have operated at 78rpm or thereabouts 
their entire lives, indeed.

It also makes sense that adding grease to the pad helps, but only for a few 
plays -- once it has cleared out of the path, the posts are again in (let's 
call it) chatter position.

In that light, would you think installing a significantly longer leather pad 
into the arbor would change its rotational position enough to place it into a 
"fresh" spot? It would also increase the return spring tension slightly, which 
may help alleviate chatter. Doesn't seem like it would take much, perhaps an 
additional 16th - 8th of an inch. It might get another 100 years of 
chatter-free use if so. Thoughts? (I've also used a spritz of WD-40 to 
lubricate the post holes -- perhaps I'll slather a fingertip of grease on them 
instead.)

I also considered sympathetic resonance, but I don't know how much the math 
lines up, considering it is a range of speeds (albeit a narrow one) while the 
60Hz vibration is more or less constant (I realize the 60Hz vibration and any 
errant governor vibration are two different things). But the hole wear, in my 
mind, lines up to that problem range quite well!

I say it often in my emails here, but it bears repeating once again: to someone 
like me who loves phonographs much more than they have technically studied 
them, this list isn't just a handy resource, it's a lifeline. Thank you, 
gentlemen.


Reporting back soon,
Robert


PS - In my defense, I never said the source of the chatter was the point of 
contact between the pad and the flywheel! I only meant to describe the symptom, 
i.e., where the noise occurred, not the underlying disease that might suggest a 
cure. I just get in a hurry sometimes. I'll try to be clearer! :-)







On Sep 12, 2019, at 3:30 PM, Andrew Baron via Phono-L 
mailto:phono-l@oldcrank.org>> wrote:

Hi Robert. Intriguing problem, and I think I may be able to shed a little 
light. My supposition could be wrong, but if you look at the physics of the 
thing, it could point to not one issue (“…obviously the contact point between 
the leather nib…”), but more likely two issues. You have to raise your 
perception above where the symptom’s cause would appear to originate, and look 
at the whole picture.

The key to solving your mystery may be directly related to something you 
conveyed very precisely, that the issue occurs over an extremely narrow band of 
speeds. So, it appears that we have a primary cause (vibration source at the 
leather and flywheel), exacerbated or amplified by a secondary condition, which 
I will assume is marginal wear in the holes that the leather pad arm’s arbor 
passes through (the first of the two axles), in possible combination with the 
holes that the speed indicator needle’s arbor passes through, in the indicator 
frame. Given that the steel arm that the leather pad mounts to is supported on 
a smaller arbor, and given that this arbor is first in line and thus closer to 
the governor flywheel where the vibration originates, it’s likely that wear 
would be more present at those holes and possibly the associated arbor as well, 
than at the larger holes and arbor of the indicator needle. The same wear on 
smaller parts will occupy a larger percentage of area, thus having a more 
noticeable effect.

The wear I describe would be very subtle. If for example, the holes that the 
indicator arbor passes through are normally three-thousandths of an inch larger 
in diameter than the arbor (just guessing on this — I have not measured it), 
and it’s known that the arbor touches only a specific portion of the wall of 
those holes at a specific speed, then you may find that the holes and/or the 
arbor itself have worn -slight

Re: [Phono-L] Credenza speed readout needle chatter

2019-09-13 Thread Ron L'Herault via Phono-L
Do not grease the pivots of the speed control indicator mechanism.  Indeed,
Victor recommended that they not be lubricated at all.  That mechanism has
to be extremely free for it to work correctly.  Since it is so sensitive,
minute variations in the operation of the governor may not show up in the
rotation of the TT due to its flywheel effect.  They may show up on the
speed control dial though.Having said that, could it be dried lubricants
at the 78 position of the indicator causing the problem.  Hit the mechanism
with carburetor cleaner spray and see if that clears up the problem.

 

Ron L

 

From: Phono-L [mailto:phono-l-boun...@oldcrank.org] On Behalf Of Robert
Wright via Phono-L
Sent: Friday, September 13, 2019 12:34 PM
To: Antique Phonograph List
Cc: Robert Wright
Subject: Re: [Phono-L] Credenza speed readout needle chatter

 

Firstly, thank you both for the detailed info!  

 

Ron, it looks like your suggestions are aimed at reducing vibration from the
governor mech itself, the application of which makes perfect sense. I just
may try that on all the motors here, in fact. Thank you!

 

Andrew, it sounds like you're suggesting that once the indicator arbor is in
(let's call it) 78rpm position, it is in that specific axis (or axes) where
the hole may have become enlarged and/or the arbor's pivot post has become
polished -- i.e., there's no chatter at other speeds because the indicator
pad is in a different position, placing the posts where the wear has not
occurred. This makes perfect sense to me, especially as the indicator
chatter happens with at least one other motor here (a spring one, not the
electric one I initially wrote about). I'm sure both machines have operated
at 78rpm or thereabouts their entire lives, indeed.

 

It also makes sense that adding grease to the pad helps, but only for a few
plays -- once it has cleared out of the path, the posts are again in (let's
call it) chatter position.

 

In that light, would you think installing a significantly longer leather pad
into the arbor would change its rotational position enough to place it into
a "fresh" spot? It would also increase the return spring tension slightly,
which may help alleviate chatter. Doesn't seem like it would take much,
perhaps an additional 16th - 8th of an inch. It might get another 100 years
of chatter-free use if so. Thoughts? (I've also used a spritz of WD-40 to
lubricate the post holes -- perhaps I'll slather a fingertip of grease on
them instead.)

 

I also considered sympathetic resonance, but I don't know how much the math
lines up, considering it is a range of speeds (albeit a narrow one) while
the 60Hz vibration is more or less constant (I realize the 60Hz vibration
and any errant governor vibration are two different things). But the hole
wear, in my mind, lines up to that problem range quite well!

 

I say it often in my emails here, but it bears repeating once again: to
someone like me who loves phonographs much more than they have technically
studied them, this list isn't just a handy resource, it's a lifeline. Thank
you, gentlemen.

 

 

Reporting back soon,

Robert

 

 

PS - In my defense, I never said the source of the chatter was the point of
contact between the pad and the flywheel! I only meant to describe the
symptom, i.e., where the noise occurred, not the underlying disease that
might suggest a cure. I just get in a hurry sometimes. I'll try to be
clearer! :-)

 

 

 

 

 

 

 

On Sep 12, 2019, at 3:30 PM, Andrew Baron via Phono-L 
wrote:





Hi Robert. Intriguing problem, and I think I may be able to shed a little
light. My supposition could be wrong, but if you look at the physics of the
thing, it could point to not one issue (“…obviously the contact point
between the leather nib…”), but more likely two issues. You have to raise
your perception above where the symptom’s cause would appear to originate,
and look at the whole picture.  

 

The key to solving your mystery may be directly related to something you
conveyed very precisely, that the issue occurs over an extremely narrow band
of speeds. So, it appears that we have a primary cause (vibration source at
the leather and flywheel), exacerbated or amplified by a secondary
condition, which I will assume is marginal wear in the holes that the
leather pad arm’s arbor passes through (the first of the two axles), in
possible combination with the holes that the speed indicator needle’s arbor
passes through, in the indicator frame. Given that the steel arm that the
leather pad mounts to is supported on a smaller arbor, and given that this
arbor is first in line and thus closer to the governor flywheel where the
vibration originates, it’s likely that wear would be more present at those
holes and possibly the associated arbor as well, than at the larger holes
and arbor of the indicator needle. The same wear on smaller parts will
occupy a larger percentage of area, thus having a more noticeable effect.

 

The wear I desc

Re: [Phono-L] Credenza speed readout needle chatter

2019-09-13 Thread Robert Wright via Phono-L
Firstly, thank you both for the detailed info!

Ron, it looks like your suggestions are aimed at reducing vibration from the 
governor mech itself, the application of which makes perfect sense. I just may 
try that on all the motors here, in fact. Thank you!

Andrew, it sounds like you're suggesting that once the indicator arbor is in 
(let's call it) 78rpm position, it is in that specific axis (or axes) where the 
hole may have become enlarged and/or the arbor's pivot post has become polished 
-- i.e., there's no chatter at other speeds because the indicator pad is in a 
different position, placing the posts where the wear has not occurred. This 
makes perfect sense to me, especially as the indicator chatter happens with at 
least one other motor here (a spring one, not the electric one I initially 
wrote about). I'm sure both machines have operated at 78rpm or thereabouts 
their entire lives, indeed.

It also makes sense that adding grease to the pad helps, but only for a few 
plays -- once it has cleared out of the path, the posts are again in (let's 
call it) chatter position.

In that light, would you think installing a significantly longer leather pad 
into the arbor would change its rotational position enough to place it into a 
"fresh" spot? It would also increase the return spring tension slightly, which 
may help alleviate chatter. Doesn't seem like it would take much, perhaps an 
additional 16th - 8th of an inch. It might get another 100 years of 
chatter-free use if so. Thoughts? (I've also used a spritz of WD-40 to 
lubricate the post holes -- perhaps I'll slather a fingertip of grease on them 
instead.)

I also considered sympathetic resonance, but I don't know how much the math 
lines up, considering it is a range of speeds (albeit a narrow one) while the 
60Hz vibration is more or less constant (I realize the 60Hz vibration and any 
errant governor vibration are two different things). But the hole wear, in my 
mind, lines up to that problem range quite well!

I say it often in my emails here, but it bears repeating once again: to someone 
like me who loves phonographs much more than they have technically studied 
them, this list isn't just a handy resource, it's a lifeline. Thank you, 
gentlemen.


Reporting back soon,
Robert


PS - In my defense, I never said the source of the chatter was the point of 
contact between the pad and the flywheel! I only meant to describe the symptom, 
i.e., where the noise occurred, not the underlying disease that might suggest a 
cure. I just get in a hurry sometimes. I'll try to be clearer! :-)







On Sep 12, 2019, at 3:30 PM, Andrew Baron via Phono-L 
mailto:phono-l@oldcrank.org>> wrote:

Hi Robert. Intriguing problem, and I think I may be able to shed a little 
light. My supposition could be wrong, but if you look at the physics of the 
thing, it could point to not one issue (“…obviously the contact point between 
the leather nib…”), but more likely two issues. You have to raise your 
perception above where the symptom’s cause would appear to originate, and look 
at the whole picture.

The key to solving your mystery may be directly related to something you 
conveyed very precisely, that the issue occurs over an extremely narrow band of 
speeds. So, it appears that we have a primary cause (vibration source at the 
leather and flywheel), exacerbated or amplified by a secondary condition, which 
I will assume is marginal wear in the holes that the leather pad arm’s arbor 
passes through (the first of the two axles), in possible combination with the 
holes that the speed indicator needle’s arbor passes through, in the indicator 
frame. Given that the steel arm that the leather pad mounts to is supported on 
a smaller arbor, and given that this arbor is first in line and thus closer to 
the governor flywheel where the vibration originates, it’s likely that wear 
would be more present at those holes and possibly the associated arbor as well, 
than at the larger holes and arbor of the indicator needle. The same wear on 
smaller parts will occupy a larger percentage of area, thus having a more 
noticeable effect.

The wear I describe would be very subtle. If for example, the holes that the 
indicator arbor passes through are normally three-thousandths of an inch larger 
in diameter than the arbor (just guessing on this — I have not measured it), 
and it’s known that the arbor touches only a specific portion of the wall of 
those holes at a specific speed, then you may find that the holes and/or the 
arbor itself have worn -slightly- out of round. It would be hard to see, but if 
the holes are normally for example .003” larger than the arbor, and now they’re 
subtly egg-shaped and .005” in only one direction (out of round), then any 
vibration whatsoever at the contact point (leather pad & flywheel) would cause 
the arbor to vibrate in a unidirectional orientation, within its holes.

Wear would naturally occur on the associated parts only in the specific 

Re: [Phono-L] Credenza speed readout needle chatter

2019-09-12 Thread Andrew Baron via Phono-L
Hi Robert. Intriguing problem, and I think I may be able to shed a little 
light. My supposition could be wrong, but if you look at the physics of the 
thing, it could point to not one issue (“…obviously the contact point between 
the leather nib…”), but more likely two issues. You have to raise your 
perception above where the symptom’s cause would appear to originate, and look 
at the whole picture. 

The key to solving your mystery may be directly related to something you 
conveyed very precisely, that the issue occurs over an extremely narrow band of 
speeds. So, it appears that we have a primary cause (vibration source at the 
leather and flywheel), exacerbated or amplified by a secondary condition, which 
I will assume is marginal wear in the holes that the leather pad arm’s arbor 
passes through (the first of the two axles), in possible combination with the 
holes that the speed indicator needle’s arbor passes through, in the indicator 
frame. Given that the steel arm that the leather pad mounts to is supported on 
a smaller arbor, and given that this arbor is first in line and thus closer to 
the governor flywheel where the vibration originates, it’s likely that wear 
would be more present at those holes and possibly the associated arbor as well, 
than at the larger holes and arbor of the indicator needle. The same wear on 
smaller parts will occupy a larger percentage of area, thus having a more 
noticeable effect.

The wear I describe would be very subtle. If for example, the holes that the 
indicator arbor passes through are normally three-thousandths of an inch larger 
in diameter than the arbor (just guessing on this — I have not measured it), 
and it’s known that the arbor touches only a specific portion of the wall of 
those holes at a specific speed, then you may find that the holes and/or the 
arbor itself have worn -slightly- out of round. It would be hard to see, but if 
the holes are normally for example .003” larger than the arbor, and now they’re 
subtly egg-shaped and .005” in only one direction (out of round), then any 
vibration whatsoever at the contact point (leather pad & flywheel) would cause 
the arbor to vibrate in a unidirectional orientation, within its holes. 

Wear would naturally occur on the associated parts only in the specific areas 
of the arbors and holes that would be in constant contact when the machine is 
set to run the correct speed, assuming that for most of the machine’s life it 
was set to run at the correct speed, thus causing the wear at those limited 
locations.

Keep in mind that even though the holes may appear to be a very close fit to 
the arbors and thus touching them all around, the reality is that the contact 
point between arbors and holes can only be over a specific small part of the ID 
of the holes. For them to touch all around, the holes would have to be the same 
size as the arbors, which would be a zero clearance, zero tolerance hole — 
almost a press fit. The holes are larger than the arbors to provide freedom of 
movement. Freedom of movement when constrained within certain engineered limits 
is a good thing. Freedom of movement outside of those limits can either cause 
problems or allow problems originating elsewhere to come to light.

Chances are that this machine has lived with a slight vibration at the governor 
most of its working life, and this has in effect caused more wear to occur in a 
very narrow and specific way. ANY vibration will lead to greater wear on 
associated parts than the same arrangement with no discernible vibration. There 
are multiple causes of vibration at the governor and pad, which could be 
explored as part of another investigation.

To correct your immediate problem, and assuming nothing is done to correct the 
vibration, then you might approach where the visible effects of this vibration 
manifest, by sourcing a different indicator frame and arbor. While the 
indicator needle serves to show the turntable speed, it also makes a marvelous 
vibration indicator!

All of the above supposition is based on imagining all of the related parts 
working in the mind, in the absence of physical inspection, and therefore 
remains in the realm of theory. To check to see if the arbor holes are worn 
slightly out of round, a clockmaker would insert a "smoothing broach" into the 
holes (tapered steel tool of round cross section), until the tool gently seats 
in the hole. Then they would hold the indicator frame and broach up to a light 
source and hunt for a slim, crescent moon shaped irregularity showing at the 
hole, around the broach. If present, this would prove a worn hole. The test 
would be repeated for each hole. Wear would likely be greater at the hole 
closest to the steel arm and hairspring that supports the pad, than at the 
opposite end of the same arbor. You should also inspect the arbors themselves, 
where they touch the holes. I would expect to see that a narrow portion of 
their OD would at minimum appear 

Re: [Phono-L] Credenza speed readout needle chatter

2019-09-12 Thread Ron L'Herault via Phono-L
I'd tighten up the governor bearing end play ever so slightly.  Check also
to see if the governor bearings are sloppy side to side.

Ron L

-Original Message-
From: Phono-L [mailto:phono-l-boun...@oldcrank.org] On Behalf Of Robert
Wright via Phono-L
Sent: Thursday, September 12, 2019 9:47 AM
To: Phono-L
Cc: Robert Wright
Subject: [Phono-L] Credenza speed readout needle chatter

Hello to all! I hope someone can help me with this incredibly annoying
problem: the speed indicator mech of one of my Credenza X's chatters at
78rpm It's fine at 80, it's fine at 90 (I have a Hughes adapter I use for
Pathé verticals), and it's fine below 77. But right at 78 to 79rpm, it
chatters. 

It's pretty obviously the contact point between the leather nib and the
governor disc -- once it's up to speed, it bounces instead of riding
smoothly against the surface. I've cleaned the disc and even held some 2400
sandpaper against it, I've replaced the leather nib with fresh leather
shoestring of two different gauges (one which was sold specifically as
material for phonograph brakes), I've soaked the nibs in oil, I've slathered
them with lithium grease… Nothing helps. I can get a few plays without
chatter if I apply more grease, or clean off the grease that's there (same
result -- "disturbing" that contact point in either way helps for a few
plays). 

Anyone else ever had to deal with this? 

Thanks in advance,
Robert


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[Phono-L] Credenza speed readout needle chatter

2019-09-12 Thread Robert Wright via Phono-L
Hello to all! I hope someone can help me with this incredibly annoying problem: 
the speed indicator mech of one of my Credenza X's chatters at 78rpm It's fine 
at 80, it's fine at 90 (I have a Hughes adapter I use for Pathé verticals), and 
it's fine below 77. But right at 78 to 79rpm, it chatters. 

It's pretty obviously the contact point between the leather nib and the 
governor disc -- once it's up to speed, it bounces instead of riding smoothly 
against the surface. I've cleaned the disc and even held some 2400 sandpaper 
against it, I've replaced the leather nib with fresh leather shoestring of two 
different gauges (one which was sold specifically as material for phonograph 
brakes), I've soaked the nibs in oil, I've slathered them with lithium grease… 
Nothing helps. I can get a few plays without chatter if I apply more grease, or 
clean off the grease that's there (same result -- "disturbing" that contact 
point in either way helps for a few plays). 

Anyone else ever had to deal with this? 

Thanks in advance,
Robert


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