I'm sure you're aware of the controversy arguing the merits of V-grooved points vs. CNC points. I don't see where either has a decisive advantage over the other. V-groove (often called spliced) points are easy to do accurately (even easier if you are content to be sloppy) and they can be made even more quickly than CNC. No special knowledge is needed & great results can be had using a variety of machines & methods. I don't believe they strengthen the forearm & prevent warpage any better than CNC points. If your wood is properly cured, you won't have any problems.
CNC points require familiarity with computer graphics programs and/or CAD/CAM programs. You must be fluent enough to understand the generated programs and be able to manually edit them. The software & machinery needed are highly specialized & require a significant investment. It's true that once you are set up, you can allow the machine to cut unattended but it hardy spits out a finished cue all by itself. It's certainly easier than using a pantograph but it's really doing the same thing, using a computer to move the tool rather than moving it yourself by hand. The process is usually much slower that installing spiced points but the benefit is that you can run a different machine at the same time, hopefully increasing your productivity.
One of the time consuming aspects of installing points is making the individual components accurately enough to allow easy assembly, good fits and accurate alignment. This is true whichever method is used to install points. CNC has an inherent advantage in this respect but V-groove point components can be as accurate as you're willing to make them. As with anything, higher accuracy usually take a little longer & demands a little more effort. Any shortcuts that don't sacrifice accuracy are obviously desirable. In busy times, if a vendor can provide a suitable finished component at reasonable cost, it makes sense to explore the option.
There is a cue component vendor who sells point blanks that are supposedly machined with nice, square corners for very reasonable prices. I discussed this with him over the phone & he assured me the surfaces were machined to a precision that would amaze me. Well, I was amazed all right. They were belt sanded kinda close to 90º but they varied by as much as 5º. This was not the precision I had hoped for. As a result, I continue to machine my own point blanks so I can control the quality to my (admittedly anal) standards. Below is a quick explanation:
This is the fixture I use to machine my point blanks
square. I tighten a rough 5/8 square up against the square shoulder of the
jig (the left shoulder as you view the pic) & machine the top surface
flat. Then I rotate the freshly machined surface counterclockwise against
the square shoulder of the jig & cut the top surface again, rotate twice
more & you have a point blank that is typically square & parallel within
less than .002".
This is a pair of Bloodwood point blanks that have been
cut to length & machined perfectly square. It doesn't take much longer to
machine them accurately vs. beltsanding them but it is time well spent.
This makes subsequent operations simpler because I can trust the
accuracy of the blanks.
By cutting the blanks diagonally at a slight skew, I can
get two points from a single blank. I am confident that each half has a
perfect 90º corner to fit
the forearm. And, more to the point (so to speak), this effectively cuts
my cost in half.
These two views show better what I mean by "cutting
diagonally at a skew".
An easier way to do this would be to just cut it in half, from corner to corner
along its length. However, this would require starting out with a much
larger square to begin with to guarantee that the base of the installed point
has enough material to permit complete cleanup at the final machining.
This shows how the points will fit into the grooves cut in
the forearm. Compare this to waste you would have by using the full,
original square.
Cutting Diagonally at a Skew
I've had lots of requests to show
exactly how I cut my point blanks diagonally at a skew.
Below, the process is clearly shown in just a few pictures:
The band saw table is offset at a 45 degree angle and my
cutting jig is shown up against the fence.
The squared point blank is tight against the stop at the rear of the jig and
will be fed through the saw.
The angle of the jig gives me the skew I need. Shown is the location of
the blade at the start of the cut.
The blade is now just beyond the midpoint of the cut. At this point,
if everything is set up properly, the saw blade will be crossing over from one
side of the point blank to the other.
The cut is finished. You can see that the blade is now on the other
side of the point blank.
The 2 finished points, ready to be inlaid into the V-grooves in the forearm.
I sell these jigs for $60
including shipping within the continental USA.
They are made from a high grade vinyl that is 1/2" thick.
Durable, easy to slide and guaranteed not to hurt a saw blade.
If you start with a reasonably true 1 3/8" X
18" square,
you can get two 3 7/8" long buttsleeves & eight 10" points
...enough to make 2 cues with matching components.
Or...you can get sixteen 9" points!
Contact me HERE and enter "skew
jig" as the subject if you're interested in purchasing a jig.
Jig Set-up
For those who purchased this jig, here are a
few hints to help you set it up quickly & accurately. I
designed this jig to be used with point blanks from 7/16” square to 7/8”
square. It will work with any
length, too. To reiterate: the idea is to cut across the diagonal of the
square at a slight skew. This gives
you an advantage in two ways: first,
it allows you to maintain the maximum width on the large end of the point blank
while still leaving something solid to support the small end of your veneers
during glue-up. And second, by
giving you a tapered blank, it makes subsequent machining of the glued up
forearm little easier.
First, tilt your bandsaw table to 45 degrees.
Next, adjust your fence to
the optimum distance from your blade. This
depends on both the length of your blank and the size of the square.
Let’s first think about what we’re trying to do here.
The saw blade will begin cutting on one side of the diagonal at the start
of the cut, then pass thru the center of the diagonal at some point, crossing
over to finish the cut on the other side of the diagonal.
Ideally, you will have 2 identical pieces after you finish your cut.
To achieve this, your blade must cross the centerline of the diagonal of
the point blank at the middle of the blank’s length.
Confusing to say but easy to do!
Measure the length of your blank. Let’s
say it’s 10” long.
Make a pencil mark half that length away from the stop on the jig – in this
case, 5”.
(Ignore the masking tape. It just makes the markings easier to see.)
Position one end of your square at the mark 5” away from the
stop.
With the blank in the
5" position, adjust your fence so the saw blade lines up exactly
with the middle of the blank.
On the left is a view from the front & on the right is a view from the
back. Note how the blade bisects the blank.
Lock your fence in position & let 'er rip. See the above section to view the
path of the blank through the saw.
This is what you'll see when you finish the cut.
If you've set it up correctly, both sections will be identical.
Just be sure to stop feeding the blank into the blade as soon as you break
through. The jig won't hurt your saw blade but you don't want to cut off
the stop.
Here is a sequence showing the glued up
forearm being machined.
It makes the process a bit clearer.
