Ferrules
There are several styles of ferrules in use today. The common variables
are:
The diameter of the tenon
Whether the tenon is threaded or not
Whether the ferrule is capped or not
The simplest option is a sleeve ferrule that slips over a tenon. The
size of the tenon can vary, depending on the strength of the ferrule
material. Many cuemakers feel a larger tenon gives a better hit
since you have a simple, direct connection between the shaft and the
tip.
Note: many imports use a sleeve ferrule made
of an "economical" material that doesn't bond well with glue. They use
ribbing inside the ferrule to provide a mechanical bond to the tenon.
It is sometimes difficult to get tips to adhere to these cues. The only
foolproof solution is to replace the ferrule with something worthwhile.
The next option relies on a threaded tenon. This provides a
mechanical bond to retain the ferrule while adding additional surface
area for glue. The threaded ferrules commercially available are tapped
5/16-18. Although this size has been used successfully for ages, some
feel this size weakens the tenon at its base. Their response is to use
larger thread sizes & machine the ferrules to their own specs.
A desirable option is to add a locating diameter at the base of the
tenon. This serves the dual purpose of adding strength while locating
the ferrule accurately on the tenon.
I have to comment on the "compression dies"
sold to make tenon threading easier. Personally, I don't like them.
While they give the illusion of a thread, you actually have less than
40% of a full thread. Think about it - the tap drill size for a ferrule
is .257" while the tenon diameter prior to running the die over it is
.280" or less. That means you're forming a thread only .011" high per
side. You call that a thread?? There's enough there to allow you to
"screw" on the ferrule & you can even tighten it up against the shoulder
if you're really careful. But you still have a tremendous volume of
empty space that must be filled with glue. And this sloppy, glue-filled
reservoir has to repeatedly absorb the most brutal shocks your cue will
experience. That can't be the best way to do this.
'Nuff said.
Both designs can be capped or not. It might depend on the material
being used or simply the preference of the cuemaker. On one hand, a
capped ferrule is unquestionably stronger & provides a consistent
surface upon which to glue your tip. On the other hand, it
introduces the opportunity for air pockets which may affect the sound of
the hit, although it shouldn't affect how it plays.
The uncapped ferrule offers the most direct connection to the shaft but
it is more likely to crack or split than a capped ferrule. This is
where the tenon diameter comes into play, forcing a compromise between
tenon diameter (solid hit) vs. ferrule wall thickness (resistance to
cracking). But then, maybe if it were threaded, the additional glue
surface will prevent it from cracking. But then...and on and on.
Now you can see why there is no consensus as to what is the best
design. As a result, I am constantly trying new materials as they
become available & as others become obsolete. Some play well but get
dirty easily. Some are too hard and squirt more than others. Some are
too soft - they play well but scratch, dent and crack too easily. Some
don't like wood glue. Etc, etc.
Follow to the next page if you aren't bored stiff already.