Extension Bumper

LocalArtist

LocalArtist

AzB Silver Member
Silver Member
Does this look like a familiar bumper brand to anyone? It’s in my collection of random bumpers so I’m not sure where it came from. I’m looking to install it but can’t find the thread count. Would I need to live thread the bumper onto the butt or do they make a tap this size? Minor diameter is .569, major is .618
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Shooter 1= Stelzenmuller, Titleist conversion-Z2

Shooter 2= Bob Frey, Bacote sneaky
 
Looks like the type of bumper that come with many of the aftermarket Mezz and Predator extensions. Those are 5/8-11. Only way to know for sure is with a thread pitch gage.
 
Those threads are a bastard thread, they are not imperial. They are non nominal size metric pitch. So good luck finding a tap, you need to cut them on the lathe or have a custom tap built. The predator ones are a little easier. They are a M16*1.5 pitch but slightly undersize, a conventional tap will work but the threads are on the loose side. From a manufacturers stand point they don't want other makers using their hardware to build cues with. What we need as small number cue builders is someone to manufacture the rubber part of the bumper in mass and sell them at a reasonable price. Not hard to turn the hardware from aluminum.
 
The mezz bumpers are not a 14mm. They are slightly bigger than 13mm. That isn't a standard thread size. I thought the pics would clarify that. My apologies if they didn't.
 
Canadian cue said:
The mezz bumpers are not a 14mm. They are slightly bigger than 13mm. That isn't a standard thread size. I thought the pics would clarify that. My apologies if they didn't.
Click to expand...
If Mike and Kim both say the tpi is 14 x 2, I believe them.
 
Canadian cue said:
The mezz bumpers are not a 14mm. They are slightly bigger than 13mm. That isn't a standard thread size. I thought the pics would clarify that. My apologies if they didn't.
Click to expand...
Ok. Thank you.
I needed to repair a Cue for a Mezz bumper. I asked and was told M14x2. I bought the tap, the fit was very good. I was happy, the customer was happy.
Job completed. All good.
Thank you for the clarification. I appreciate you.
 
I believe what you occasionally run into is that the minor and major tolerances are already built into certain dies and taps.
13.(almost 3) should thread into a 14 tap hole with about the right amount of tolerance.
For instance ...unless they're special made, a 3/8 tap rarely measures .375 from what I have found. Usually larger into the .380 range

Food for thought..........

I run a lot of "bastard" threads in my cues so I can get the fit I'm looking for depending if glue is involved or not.
 
So just for clarification, according to the Machinery handbook which is pretty much the Machinists Bible the pitch diameter of a M14x2.0 should be between 12.663 mm and 12.503 mm. I measured the pitch diameter of the Mezz bumper and it is 11.709. Which is a mile out of tolerance for an M14 thread. So it is indeed a bastard thread. Which was my point from the start. Yeah the bumper will thread into a hole threaded for an M14 but it will be beyond loose. To put it into imperial numbers we are talking 0.024" under size on the pitch diameter.
This is a good example of where people rely on what they read on the forums and take it as fact. The manufacturers like Mezz don't want to share their hardware with everyone else, tried buying the wavy pin tap lately. They obviously build there own tooling to fit their hardware. This industry is riddled with proprietary stuff. Just look at all the ridiculous thread pitches that are being used.
 

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Canadian cue said:
So just for clarification, according to the Machinery handbook which is pretty much the Machinists Bible the pitch diameter of a M14x2.0 should be between 12.663 mm and 12.503 mm. I measured the pitch diameter of the Mezz bumper and it is 11.709. Which is a mile out of tolerance for an M14 thread. So it is indeed a bastard thread. Which was my point from the start. Yeah the bumper will thread into a hole threaded for an M14 but it will be beyond loose. To put it into imperial numbers we are talking 0.024" under size on the pitch diameter.
This is a good example of where people rely on what they read on the forums and take it as fact. The manufacturers like Mezz don't want to share their hardware with everyone else, tried buying the wavy pin tap lately. They obviously build there own tooling to fit their hardware. This industry is riddled with proprietary stuff. Just look at all the ridiculous thread pitches that are being used.
Click to expand...
I shall see. I just ordered an
M13x2 tap.
The wavy screw tap is available from 2 sources. One here in the U. S. And one from China.
 
Sure the wavy pin is available for 436$...as for the Chinese knock off I guess you would have to buy one and find out how good it is. With the Chinese stuff it is always a gamble. Just picked up a tail stock for an indexer and it was a Chinese knock off. Looked great at first appearances, then started to measure and indicate the various reference surfaces and it was total crap.
 
Canadian cue said:
Sure the wavy pin is available for 436$...as for the Chinese knock off I guess you would have to buy one and find out how good it is. With the Chinese stuff it is always a gamble. Just picked up a tail stock for an indexer and it was a Chinese knock off. Looked great at first appearances, then started to measure and indicate the various reference surfaces and it was total crap.
Click to expand...

Hahahaha
The correct answer is, and always has been.
Pay now or pay later.
My Industry humor!
 
Canadian cue said:
The mezz bumpers are not a 14mm. They are slightly bigger than 13mm. That isn't a standard thread size. I thought the pics would clarify that. My apologies if they didn't.
Click to expand...
I bought an m13x2 tap. I'm lucky the Mezz bumper didn't rip apart. I'll stick with the m14x2.
 
Kim Bye said:
Looks like the type of bumper that come with many of the aftermarket Mezz and Predator extensions. Those are 5/8-11. Only way to know for sure is with a thread pitch gage.
Click to expand...
If you don't have a thread gage take it to the hardware store and see if it fits and of the nuts there.
 
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