New musical toy

Rennie Heuer

Moderator
Staff member
Messages
9,241
Location
Constantine, MI
Wow, that's quite the split!It looks like it was cut from a cross section of the tree, much like you might turn a bowl. If so, then the split s not so hard to understand.
 

Jim DeLaney

Moderator
Staff member
Messages
5,960
Location
Austintown, Ohio
Tom,
Is that a wide split. or is there a piece missing? From the photo, it looks more like a missing piece (and tooth).
Also, does the number printed on the gear indicate the number of teeth?
It wouldn't be "authentic," but a new gear made from Baltic Birch plywood would preclude any further splitting problems.
 

Tom Baugues

Member
Messages
2,609
Location
Lafayette, Indiana
Wow, that's quite the split!It looks like it was cut from a cross section of the tree, much like you might turn a bowl. If so, then the split s not so hard to understand.
Yes, that’s what it looks to me like as well. I think I’ve got a pice of hard maple out in the shop that I’ll try to make this out of.



Sent from my iPhone using Tapatalk Pro
 

Tom Baugues

Member
Messages
2,609
Location
Lafayette, Indiana
Tom,
Is that a wide split. or is there a piece missing? From the photo, it looks more like a missing piece (and tooth).
Also, does the number printed on the gear indicate the number of teeth?
It wouldn't be "authentic," but a new gear made from Baltic Birch plywood would preclude any further splitting problems.
Jim, I think the number is the number assigned to that barrel that identifies it as having those tunes on it. (I think). I’m still researching this stuff.
This gear has 32 teeth.

Sent from my iPhone using Tapatalk Pro
 
Last edited:

Don Baer

Moderator
Staff member
I decided to remove the barrel from the piano last night to look at the “broken tooth”. What I discovered is not what I was expecting. The wooden gear had actually “split” and the opening was actually a wide gap not a missing tooth. So, I’m hoping I can still use it as a pattern to cut a new gear.
It’s probably still going to be another 6-8 weeks before I get to work in my shop due to the cold weather but this at least gives me a heads up on what I’ll need to do.



Sent from my iPhone using Tapatalk Pro
neat, I would try to make one out of Baltic birch. It looks like there is a number on it "89" or "68".... :unsure:.... Jim beat me to the punch
 

Darren Wright

Administrator
Staff member
Messages
16,077
Location
Kansas City, Missouri
It wouldn't be "authentic," but a new gear made from Baltic Birch plywood would preclude any further splitting problems.
I also agree with Jim, just be sure the roll is spinning freely/correctly though, as a jamb/bind may have caused the old teeth to break. It looks like the spiral drive gear would be much harder to fix it it wasnt spinning correctly.
 

Vaughn McMillan

Administrator
Staff member
Messages
32,261
Location
ABQ NM
You can see the pith in the photo of the gear, so it was definitely a cross section of the tree or branch. That'd be pretty much guaranteed to crack and split. It also looks to me like the gear's already been patched once before, and the missing chunk might have been from a second repair attempt. Looks like it should be pretty straightforward to come up with a new, more stable gear though. :thumb:
 

Ryan Mooney

Moderator
Staff member
Messages
5,794
Location
The Gorge Area, Oregon
Interesting, I can't quite tell from the picture but is the gear centered on a set of growth rings like a cookie cut from the end of a tree? That would explain the radial split, and it sort of opens up the question of why they would make it like that? Easier to carve I suppose?

I think what I'd do is measure the expected radius on the unsplit side of the inside and outside of the gears.. Step off the expected spacing with a divider and get the layout that way, that would let me adjust for minor variations in d. It looks like the teeth are at a chord off of the centerline though so that might throw a small wrench in that plan. Alternatively I'd bet that the unsplit side could be used to make the patter for both sides...
 

Kerry Burton

Member
Messages
1,129
Location
Orem, Utah
With all CAD expertise on this forum, it seems like someone could fairly easily create a printable (and precise!) PDF template for you, given:
  • The outer diameter of the gear
  • The diameter at the base of the teeth
  • The tooth count
  • (Optional) The approximate angle from the tip of a tooth to the base of the next (or previous) tooth
I'm not sure I could do it though. "Anyone? Anyone?"
 

Paul Douglass

Member
Messages
3,985
Location
S E Washington State
I just did a search on these instruments and there appears to be some info, site, forums about them. While you shop gets warm, you could probably find out about anything you want to know. Might even be some parts, overseas....
 

Tom Baugues

Member
Messages
2,609
Location
Lafayette, Indiana
I just did a search on these instruments and there appears to be some info, site, forums about them. While you shop gets warm, you could probably find out about anything you want to know. Might even be some parts, overseas....
Paul, I have found one “Facebook” group so far. I have also found a couple of people who have restored these before. I will be asking questions of them as well. These are not necessarily rare but just not a lot of published information about them is available.


Sent from my iPhone using Tapatalk Pro
 
Top