Making a Threaded Joint Collar From an Old
Cueball
I like SS joints but a nice, white joint is the next best thing. It's
hard to beat the beauty of ivory but some prefer environmentally
friendly materials. Most of the alternatives are sold only as tubing,
allowing the builder to simply slide on the tubing with a little glue.
And it works. There's nothing wrong with that method.
But I like a mechanical bond that reinforces the glue bond. It's very
satisfying to tighten a collar and its trim rings, generously slathered
in glue, up against a shoulder. The excess glue is squeezed out & there
is a sense of finality when the collar is drawn up to a positive stop.
You just KNOW it won't loosen.
Unfortunately, there aren't many white alternatives that come in solid
rod form & avail themselves to being threaded. We won't even consider
the thermoplastics as they are just too soft. Elforyn & Juma are
two easy-to-machine materials that I have used successfully as joint
collars. But sometimes I prefer something just a little harder.
I often make ferrules & joints from old cueballs. They are strong &
take a beautiful polish. However, it takes a lot of work to get the
most out of a cueball. I am able to get 7 ferrules or 3 joint collars
out of one cueball. One thing I should mention: while these are a
beautiful ivory color when first made, they will yellow over time - just
like a cueball. So far, nobody has ever complained and I have many out
there that are over 10 yrs old.
There are several ways to make the joint collars from a cueball.
Below, I will show the "manual" method that anybody can do with basic
shop equipment and
HERE, I'll show
an advanced method using
CNC to speed up
the job. Yet a 3rd method is shown
HERE.
OK, this is your basic old cueball. This ball is (or used to be) 2
3/8" diameter. It is now .030 to .045 undersize, depending on where you
check it.
I cut the ball down to 1.060 thickness, taking half off each side.
While it's in the lathe, I drill a hole in the center. This will
provide a machined surface that is square to the face. In the 2nd pic,
you can see my layout that will be my guide when cutting out the 3
collars on a bandsaw. The layout is for 3 joint collars, each .920 in
diameter.
This is how I chuck up on the freshly sawn collars. The previously
drilled center hole helps line up the blank perpendicular to the exposed
face. It isn't perfect but it sure makes it easy to get them very
close. In this particular instance, it took less than 60 seconds to
find center & the face ran within .002". With the collar blank running
true, drill & bore a hole to fit a 3/8 arbor. Don't worry about truing
up the faces. That can all come later.
Here are both sides of the collar with the 3/8 hole. You can see
the remnants of the drilled hole in the 2nd pic. Now the collar can be
installed on a 3/8 arbor, allowing the OD to be turned concentric with
the 3/8 hole.
And a look at the finish turned diameter.
Now that the OD is done, you can drill, bore & tap the collar.
Lately, I've been cutting my ferrule & joint collar threads with live
tooling instead of taps because the results are so much cleaner & you
can machine a full thread all the way to the shoulder. Personally, I
like a .500 bore for the exposed face of the collar and 5/8-18 x 3/4"
deep threads on the other end. Of course, you would face the threaded
end at this time to guarantee the face is square with the threads. The
other face won't need finishing until the cue is ready for a joint pin.
And here's the finished product.
Maybe this will help justify why I charge so much for a cueball joint.
Again,
THIS LINK will take you to
another page showing the above procedure done by CNC.
A supplement:
A few have asked how to lay out the 3 equally spaced holes on the face
of the cueball. Originally, before I had my CNC machine, I just
constructed 3 equally spaced lines & experimented with different radii &
blank diameters until I found a something that worked. It seems that is
a lost art gone the way of the slide rule. Now, I have the luxury of
CAD to simplify my job. To make it easier for you, I'm including a
sketch showing the rectangular dimensions needed to lay out your
cueball. It might be easier to layout a piece of paper & transfer it to
the ball. All you really need to do is lay out the 3 center points on
the face of the cueball, prick punch, then lay out the (3) .920 diameter
holes from the punch marks. Then it's off to the band saw.
click on the sketch
Another supplement:
I have some time to kill so here's a quick lesson on how to construct a
hex, which will allow you to divide a circle into 3 or 6 equally spaced
segments. Start by drawing your desired radius with a compass - in this
case, we'll use .590 as required above. Then pick a point - any point -
in this case, Point "A" in the sketch below. Take your compass, which
is still set to a .590 radius and draw an arc from point "A" that
intersects your base circle. Now draw another arc using this
intersection point as your base. And another. And so on. It just so
happens that constructing a set of 6 arcs equal to the radius of a
circle will divide that circle into 6 equal segments. Without getting
too far into it, it's easily explained by the relationship between the
hypotenuse & the short leg of a 30-60-90 triangle in which one is twice
as long as the other. Anyway, I've effectively killed this bit of time
so I'll quit now.
click on the sketch
Making a set of Joint Protectors from an old
cueball.
It's a simple matter to make a JP from a cueball. If you want more than
one JP, the easiest solution is to make each from a separate cueball.
But in the interests of using old cueballs efficiently, it is worth the
effort to get all you can from each ball. A customer wanted 2 joint
protectors for his 3/8-10 equipped cue & I assumed my method shown above
would work, allowing me to get 3 JPs from each cueball. However, the
butt JP needs to be 1.200 long to completely protect the joint pin.
This increase in ball thickness doesn't leave as large a flat section as
when the cueball is cut to 1" thickness. This limits me to only 2 long
JPs per cueball. This makes for an easier layout but I used the CNC
simply because it was there. The following pictures show my procedure
for these simple yet beautiful JPs.
Here is the cueball cut to 1.250" thick with the JP diameters laid
out and .250" construction holes added. The construction holes will be
tapped 5/16-18 so the JPs can be mounted on a threaded arbor for further
machining. As you can see, one hole is tapped already.
After both holes are tapped, I remove the excess stock on my bandsaw.
Here you can see the rough JP mounted on the threaded rod.
Once in the chuck, it's easy to turn the OD concentric with the 5/16
threads.
Now that there is a reliable outside diameter to work from, I
can bore the tapped hole oversize to allow re-tapping 3/8-10. Once
that's done, I can mount the JP on a 3/8-10 arbor and finish the
diameter & the length in relation to the new threads.
Here are two views of the finished JPs. No finish is needed on
them...just some polishing to bring out the shine. Simple &
very attractive.