4Woods Shoulder Noise

Kira-sama · Post by **Kira-sama** » Thu Oct 17, 2019 9:42 pm

katiesBoyfriend wrote:I opened up her shoulder earlier this evening. I cleared out some foam inside the shoulder joint and then I took it apart. The nut was on rather tight, so I needed a bit more torque on my ratchet to loosen it. I looked at everything and I didn't notice anything unusual. I put it all back together, though not without making use of my vocabulary of profanity. :wink:

I'm not too keen on the metal-to-metal contacts in that joint. If I had designed it, I would have used nylon washers instead of metal on the inside surfaces and allowed for a corresponding clearance inside the bracket. Nylon is commonly used as a bearing material and nylon washers are readily available from hardware stores.

Anyway, I can move her arm out like it's supposed to. I'll start closing up the incision tomorrow.

That's good to hear. Probably was the tightness of the joint that prevented it from moving. Is the squeaking noise still there?

katiesBoyfriend · Post by **katiesBoyfriend** » Thu Oct 17, 2019 11:00 pm

Kira-sama wrote:
katiesBoyfriend wrote:I opened up her shoulder earlier this evening. I cleared out some foam inside the shoulder joint and then I took it apart. The nut was on rather tight, so I needed a bit more torque on my ratchet to loosen it. I looked at everything and I didn't notice anything unusual. I put it all back together, though not without making use of my vocabulary of profanity.

I'm not too keen on the metal-to-metal contacts in that joint. If I had designed it, I would have used nylon washers instead of metal on the inside surfaces and allowed for a corresponding clearance inside the bracket. Nylon is commonly used as a bearing material and nylon washers are readily available from hardware stores.

Anyway, I can move her arm out like it's supposed to. I'll start closing up the incision tomorrow.
That's good to hear. Probably was the tightness of the joint that prevented it from moving. Is the squeaking noise still there?

I heard it, but not as loud.

It seems to be coming from the replacement cross piece for her back that I made and installed a few weeks ago.

If that's the source, I think I know what's going on. When I made the piece, the inner diameter was a bit larger than the outer diameter of the shaft stub for the shoulder assembly. Part of that was because the OD of the hole saw was just a bit bigger than the OD of the shaft, the fit is a bit looser than it probably was originally. I suspect that the noise comes from the contact between the cross piece's PVC and the steel of the shaft.

I think I know why the noise was louder. The tightness of the shoulder joint made the combined arm and shoulder assemblies act like a solid piece. Any movement of the arm in certain directions would have resulted in more torque acting at the contact point. Now that the arm is a lot looser, there might not be as much torque at that location.

I might know more after I close her up.

Kira-sama · Post by **Kira-sama** » Fri Oct 18, 2019 7:44 am

katiesBoyfriend wrote:
Kira-sama wrote:
katiesBoyfriend wrote:I opened up her shoulder earlier this evening. I cleared out some foam inside the shoulder joint and then I took it apart. The nut was on rather tight, so I needed a bit more torque on my ratchet to loosen it. I looked at everything and I didn't notice anything unusual. I put it all back together, though not without making use of my vocabulary of profanity. :wink:

I'm not too keen on the metal-to-metal contacts in that joint. If I had designed it, I would have used nylon washers instead of metal on the inside surfaces and allowed for a corresponding clearance inside the bracket. Nylon is commonly used as a bearing material and nylon washers are readily available from hardware stores.

Anyway, I can move her arm out like it's supposed to. I'll start closing up the incision tomorrow.
That's good to hear. Probably was the tightness of the joint that prevented it from moving. Is the squeaking noise still there?
I heard it, but not as loud.

It seems to be coming from the replacement cross piece for her back that I made and installed a few weeks ago.

If that's the source, I think I know what's going on. When I made the piece, the inner diameter was a bit larger than the outer diameter of the shaft stub for the shoulder assembly. Part of that was because the OD of the hole saw was just a bit bigger than the OD of the shaft, the fit is a bit looser than it probably was originally. I suspect that the noise comes from the contact between the cross piece's PVC and the steel of the shaft.

I think I know why the noise was louder. The tightness of the shoulder joint made the combined arm and shoulder assemblies act like a solid piece. Any movement of the arm in certain directions would have resulted in more torque acting at the contact point. Now that the arm is a lot looser, there might not be as much torque at that location.

I might know more after I close her up.

It'll probably disappear when she is resealed. The rest of the noise will probably be absorbed by the silicone if it's not too loud right now with her shoulder open.

katiesBoyfriend · Post by **katiesBoyfriend** » Tue Oct 22, 2019 4:30 pm

Kira-sama wrote:
katiesBoyfriend wrote:
<snip>

I might know more after I close her up.
It'll probably disappear when she is resealed. The rest of the noise will probably be absorbed by the silicone if it's not too loud right now with her shoulder open.

Unfortunately, the noise is still there. It started after I finished the back repairs, so I think it's related to what I did. I'm just not sure where the source is.

Kira-sama · Post by **Kira-sama** » Tue Oct 22, 2019 9:03 pm

katiesBoyfriend wrote:
Kira-sama wrote:
katiesBoyfriend wrote:
<snip>

I might know more after I close her up.
It'll probably disappear when she is resealed. The rest of the noise will probably be absorbed by the silicone if it's not too loud right now with her shoulder open.
Unfortunately, the noise is still there. It started after I finished the back repairs, so I think it's related to what I did. I'm just not sure where the source is.

Only I thing I would suggest is to try to remove the new crosspiece and see if the noise is still there. If it is, then it's not the crosspiece and then you can try using a stethoscope to pinpoint the location of the noise.

katiesBoyfriend · Post by **katiesBoyfriend** » Tue Oct 22, 2019 11:10 pm

Kira-sama wrote:
<snip>

Only I thing I would suggest is to try to remove the new crosspiece and see if the noise is still there. If it is, then it's not the crosspiece and then you can try using a stethoscope to pinpoint the location of the noise.

Removing the crosspiece is something I really don't want to do. It was a miserable job putting it in--twice, as it turned out.

I haven't checked to see if the other shoulder's making any noise. However, the one in question feels a bit loose, so it could be that the joint needs to be tightened. Considering its location, though, I haven't foggiest at the moment as to how I'd do it.

Kira-sama · Post by **Kira-sama** » Wed Oct 23, 2019 10:03 am

katiesBoyfriend wrote:
Kira-sama wrote:
<snip>

Only I thing I would suggest is to try to remove the new crosspiece and see if the noise is still there. If it is, then it's not the crosspiece and then you can try using a stethoscope to pinpoint the location of the noise.
Removing the crosspiece is something I really don't want to do. It was a miserable job putting it in--twice, as it turned out.

I haven't checked to see if the other shoulder's making any noise. However, the one in question feels a bit loose, so it could be that the joint needs to be tightened. Considering its location, though, I haven't foggiest at the moment as to how I'd do it.

I was going to post this option before, but wasn't sure if it made any sense or was possible: If the noise isn't from something serious that is damaging or is going to damage your doll, then maybe you could try some sort of insulation to absorb the noise.

katiesBoyfriend · Post by **katiesBoyfriend** » Wed Oct 23, 2019 1:21 pm

Kira-sama wrote:
I was going to post this option before, but wasn't sure if it made any sense or was possible: If the noise isn't from something serious that is damaging or is going to damage your doll, then maybe you could try some sort of insulation to absorb the noise.

Looking at the picture of the skeleton, there are two joints in the shoulder assembly. It's just that I'm not quite sure as to which one is wonky. In addition, because of the construction and materials used, I might be hearing the sound at one location while the actual source could be elsewhere.

Kira-sama · Post by **Kira-sama** » Wed Oct 23, 2019 2:36 pm

katiesBoyfriend wrote:
Kira-sama wrote:
I was going to post this option before, but wasn't sure if it made any sense or was possible: If the noise isn't from something serious that is damaging or is going to damage your doll, then maybe you could try some sort of insulation to absorb the noise.
Looking at the picture of the skeleton, there are two joints in the shoulder assembly. It's just that I'm not quite sure as to which one is wonky. In addition, because of the construction and materials used, I might be hearing the sound at one location while the actual source could be elsewhere.

Maybe if you dismantle/loosen one joint and move the other joint, then maybe it will help to pinpoint the location.