S&W wheel burners - Check this out.

[tfparatech]

I bought this 686 new and put this picture up on the forum earlier because of the weird divot on the cylinder. Nobody recognized it ( I sure didn't) so I sent it back.

It came back without work. The paperwork said that the "mark on the cylinder is part of machining process, all new cylinders have this marking."

I have wheels that are less than 3 years old that don't have this. anybody out there have a new gun with this on their cylinder?

Is this because they switched to CNC? Appreciate any input - thanks.

 

[williamlayton]

Is the coffee a little strong or are you prone to being anal"
Just saying that I wouldn't be concerned buttttt---that is just me.
Blessings

 

[Mickey D]

It's a match for the hole in the frame above the cyl release.

 

[rbmcmjr]

Blue sky speculation here: Is there a corresponding protrusion on the back of the extractor star? This might serve as a replacement for the pins that locate the star on older models.

 

[BigBill]

Is the spot drill on the cylinder is what your talking about? That spot can be used for locating the cylinder for machining in a fixture. I can align the cylinder flutes to the bored holes / loc up location so its all spot on when it gets machined.

 

[diamonback68]

I'm just wondering why you care since it's hidden under the ejector star anyway. Older guns have pins sticking up.

 

[andyo5]

I checked all six of mine. None of them have that mark.
Not sure from your post, but it looks like you had sent it back to the factory for some reason. If they worked on the cylinder, that must be when it was done. I doubt it will do any harm and it is normally hidden, so maybe you need not worry about it.

 

[-db-]

If S&W says they're putting it on all newer cylinders, it's likely a small relief put there to capture oil/crud during operation or something like that. I doubt it's a fixture/jig locating point, being off-center (I would assume everything- chambers, flutes, etc.- is located off the exact center axis of the cylinder).

 

[rwsmith]

index

I agree with Big Bill. I think it is an index for the cnc. Reference point for rotation for cylinder ops such as drilling, flute milling. It is better for the indent NOT to be centered for indexing rotation repeatability.

 

[-db-]

I agree with Big Bill. I think it is an index for the cnc. Reference point for rotation for cylinder ops such as drilling, flute milling. It is better for the indent NOT to be centered for indexing rotation repeatability.

I'm curious, why is off-center better? It's been more than 20 years since I've turned handles (that's what machinists did before CNC became the norm). I don't recall ever indexing a part off-center if center-indexing was possible.

 

[tfparatech]

Thanks for all the feedback guys. I was curious because it isn't on any other gun I have. The CNC explanation makes the most sense. Thanks again.

 

[-db-]

There aren't many videos portraying revolver cylinder machining out there, and the three I've found don't show us the whole picture, but they do show the cylinders being indexed at center:

Heritage Rough Rider: Tour of Heritage Manufacturing Inc. part 3 - YouTube
How It's Made - Uberti Revolvers - YouTube
Machine-Cylinder - YouTube

I'm still trying to wrap my head around how indexing at some random off-center axis could possibly be better. From a CNC programming viewpoint, it would involve so much more math, for one thing.

 

[C Islander]

I don't have anything constructive to add to this thread, but I'd like to know what a "wheel burner" is??

 

[scooter123]

That's someone who takes anything that doesn't fit to a grinding wheel to make it fit. By nature a very close relative of the infamous Wood Butcher.

 

[tfparatech]

I don't have anything constructive to add to this thread, but I'd like to know what a "wheel burner" is??

People who shoot revolvers.