It becomes another bastard joint that way?
compression joint
- Thread starter nipper
- Start date
It becomes another bastard joint that way?
Not those who understand what the term means.
BTW having the insert bottom out against the butt is a terrible idea.
Dale
I don't know how someone can tell if the insert bottomed out outside of seeing a gap in the joint faces.
OK, I'll paint a picture. You tell me how pretty it is.
The following numbers aren't actual. Plug in the ones that work for you.
Your pilot recess (in the jnt-collar) is .250" deep.
The exposed length of the shaft's pilot is .2495" long.
Depending on the amount of torque applied during connection, the brass insert elongates (stretches)
.0005" and you've just bottomed-out and not realized it. No gap would be visible at the jnt.
You'd have perfect right up until you hit a ball. From there on you'd hear it.
Tee Hee, I know but it could happen. The reverse is also true, pin bottoming in the shaft.
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It's not needed, I just felt like fooling around but it turns out that this particular 'bastardized' joint increases the amount of actual material contact between the shaft and butt by over 79% It also gives the stiffness of a radial screw as well as the hit of nickel silver. If that isn't enough the front of the cue is a great piece of heart wood birds eye maple. Don't know for sure how it plays,but on paper it should never miss, and if somehow it does, at least it would feel great. My mother used to say "an idle mind is the Devil's workshop" which accounts for this experiment so I refer back to my original post and say WHY NOT.
Thank you!!
Thank you for after 40 years still continuing to improve the cue building industry. Pool players don't know how lucky they are to have people like yourself and the other cue builders who continuously work to improve the craft and not just turn out the same without ever contemplating, considering, and attempting new ideas. Tom
Thank you for after 40 years still continuing to improve the cue building industry. Pool players don't know how lucky they are to have people like yourself and the other cue builders who continuously work to improve the craft and not just turn out the same without ever contemplating, considering, and attempting new ideas. Tom
I realize this thread has run its course, but it came to mind when the set of shafts below came into my shop this week.
The 5 on the right are all compression joints, but notice the pilot isn't always in the same direction - I had not seen this before.
Just thought some of you might be interested.
I don't remember all the makers, but I do believe a couple are of Bryan Mordt's creation.
FYI
Gary
The 5 on the right are all compression joints, but notice the pilot isn't always in the same direction - I had not seen this before.
Just thought some of you might be interested.
I don't remember all the makers, but I do believe a couple are of Bryan Mordt's creation.
FYI
Gary
Attachments
Gary,
Of the 5 shafts you've stated as having a pilot, only one actually has a pilot.
It's the one that has the insert projecting from the face of the shaft.
That little oddity IS the pilot and it does appear to be of the 'compression' type.
All the rest are 'flat-faced', not piloted so there is no compression being done.
HTHs, KJ
Of the 5 shafts you've stated as having a pilot, only one actually has a pilot.
It's the one that has the insert projecting from the face of the shaft.
That little oddity IS the pilot and it does appear to be of the 'compression' type.
All the rest are 'flat-faced', not piloted so there is no compression being done.
HTHs, KJ
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Good Morning KJ,
I'm just wanting to understand - maybe I'm the only one who doesn't get it.
I thought any of the joints with a domed shape were considered "compression" joints, regardless of whether the pilot protruded from the shaft or from the butt. But what I hear you saying is that only the joint with the domed pilot on the shaft that is pulled into the socket of the butt is a compression joint. Am I reading you correctly?
Thanks for your insight,
Gary
I'm just wanting to understand - maybe I'm the only one who doesn't get it.
I thought any of the joints with a domed shape were considered "compression" joints, regardless of whether the pilot protruded from the shaft or from the butt. But what I hear you saying is that only the joint with the domed pilot on the shaft that is pulled into the socket of the butt is a compression joint. Am I reading you correctly?
Thanks for your insight,
Gary
I'm not a cue maker, but I've always been under the impression that you had to have "compression" if it is to be considered a compression joint. The only ones I've seen that provide compression are the ones that have wooden extensions on the shaft inserts that fit "snugly" down into the joint cavity on the butt.
Hi HawaiinEye,
I understand what you are saying. But if the butt has a wooden domed extension that fits snugly into the shaft cavity, is that not the same?
I'm trying to avoid the discussion of whether any real compression is achieved as that has been thoroughly discussed before.
Maybe it is not clear from my picture, but those other 4 shafts on the right, which do not not have a male extension, do in fact have a domed concave interior.
The shaft on the left, with the "reverse" pin, and the 2 3/8-10's next to it are flat faced joints to be certain.
What do I call the other 4 in the future so I am speaking the same language as others?
Thanks
Gary
You may be confusing the chamfer at the entrance to the shaft to be the pilot; it's not.
At least not in the context presented in this thread.
That chamfer does a couple of cool things but compression isn't one of them.
As the pin from the handle approaches the shaft for connection, that bevel/chamfer
directs the pin to the shaft's threads. I suppose you could say that it
pilots the pin in a sense and that may be where the confusion lies.
The second thing that chamfer does is to provide a center for later operations that require one.
In order for that to happen though, the chamfer has to be absolutely concentric with the threads in the shaft's insert.
Internal threading of the insert and the chamfer must be done at the same time.
Today's CNC technology does an insert, start to finish, without leaving the chuck.
This insures that everything about the insert is concentric.
Again, your pic does show a shaft with a true pilot; the one with brown collar and dash ring-work.
The exposed wood of the pilot grazes the interior wall of the jnt collar during connection
and 'pilots' the shaft to center itself on the pin and jnt. collar.
On a 'compression-jnt', that wood is very slightly compressed and can be felt during final cinch.
HTHs, KJ
One way is to use an indicator like Prussian Blue.
https://en.wikipedia.org/wiki/Engineer's_blue
I don't think this would be ideal for wood, maybe something like powdered graphite would be a better choice.
https://www.homehardware.ca/en/rec/...owder-Graphite-Lubricant/_/N-ntjiv/R-I8640303
Either way, put some on the insert, screw cue together, unscrew cue, look for transferred indicator in bottom of hole.
Dave
Does anyone remember the piloted chamfered pins/inserts Porper used to offer years ago! Used to own a Porper jump/break. Made from tiger maple, including the shaft. Remember it as being the stiffest hitting cue I've ever played with. Sorry I ever sold that cue for $125. Would love to get it back if anyone's got one.