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Common dilemma - is there a tap i can simply purchase to have my 3/8-10 shaft fit a 3/8-10 modified pin?
Common dilemma - is there a tap i can simply purchase to have my 3/8-10 shaft fit a 3/8-10 modified pin?
3/8-10 shaft fit a 3/8-10 modified pin
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Would a drill work
A 5/16 drillbit is about .004 larger so I dont know
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Because of the slop?How would you open up the minor? Curious if just running the tap thru would open it up
SSDiver2112
Esscot Custom Cues
Everytime this question comes up Bob’s web page explaining this comes up lol.
The threads on the outside are the same. The minor is different so re-running the tap does nothing.
Basically, the inner hole is narrower on your shaft than you need to accommodate the fatter inner diameter of the modified pin. Trimming off the inner part of the threads in your shaft is the goal. Boring them out is ideal. Reaming next and drill bit last. A lathe is needed to ensure centering that using a drill cannot do.
You bore and ream.
This is the best answer.
I was not talking about a drillbit in a drill. I was curious about a drillbit in a tailstock
Yes, and .312 (5/16)will work just fine Either one .308 reamer or a .312 drill bit in a lathe that is centered from the chuck to the tailstock dead nuts
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depends on the type of drill bit. A solid carbide 3 or 4 flute would be the best as regular bits can and will wander. The whole deal with the modified is to align the pin on center everytime you screw the cue together....if the bit wanders.....see the issue? boring is the best option or a reamer
I would be more worried about chuck and tailstock accuracy in this case. A sharp bit or a ream is not likely to wander cutting so little material.
The beauty of boring is that your hole can be perfect. All that's left is to get the shaft centered in the chuck and spinning on the proper axis.
The beauty of boring is that your hole can be perfect. All that's left is to get the shaft centered in the chuck and spinning on the proper axis.
Have I been doing these wrong the whole time. I've always used 5/16 to drill the hole for a 3/8-10 thread tap. I haven't had an issue with my 3/8 shafts fitting on a modified pin.
SSDiver2112
Esscot Custom Cues
I did a few at first like that too. My current shaft was done that way. 5/16 (0.312) will work because the threads will still cinch it down tight. Boring it to 0.308 is more accurate and I also use a tight fit tap. The shaft feels less sloppy while screwing it on. Both work but .308 is better because it is more accurate to the pin.
Is that .308 to the regular pin or the flat.
I don't do many 3/8 pins the last few years. It just seems like .308 gives the joint a more snug fit but 5/16 is still an acceptable hole to start with. 10 years in and still learning stuff.
Yes it works as long as you get straight center. go figure most of those guys thread up a modified shaft on a standard 3/8-10 pin a bigger difference from .004 that a 5/16 bit would give you.
I use a .312 reamer on all my shafts that im threading into phenolic for a modified pin
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