Luthier Tips du Jour - The V Joint


Uploaded by OBrienGuitars on 12.06.2010

Transcript:
The V joint is used to attach the peghead to the guitar.
It has been around since the 18th century.
It was even used by C.F. Martin in the 1800’s.
In the 20th century it has been used by Hermann Hauser Sr.
and José Romanillos among many other well known makers.
Whether or not the V joint is more structurally sound than another type of joint
is debatable. However,
a well executed V joint is without a doubt a thing of beauty
as well as a great way to show off your skills as a craftsman.
In this video I am visiting with luthier Bill Nesse
in his shop in Northern Colorado.
Bill studied with Romanillos in Spain and uses the V joint on all his guitars.
He graciously accepted my invitation to show how he executes this joint.
Bill starts with a neck blank that is at least 25mm or about one inch thick.
Any thinner than this and you are limited in the angle you can make with the peghead.
After squaring and thicknessing the wood,
making sure that both sides are parallel,
you need to place a centerline on the full length of the neck blank
on both the top and bottom.
For consistency, all markings for the joint are made referencing
the same edge of the neck blank.
The length of the peghead, that will be cut off
from the rest of the neck blank, depends on your peghead design.
Bill cuts his at about 20cm or 8 inches.
This leaves a little excess on each end.
It is important to make sure this cut is nice and square.
Align the two pieces like they were before the cut.
The length of the V is about 40mm.
Any longer and it can run into the tuner area.
The width is between 34 and 38mm depending on how wide you want the neck.
On this guitar Bill is using 36mm for the width.
Use a sliding bevel and a sharp knife to mark these lines on the peghead.
Then transfer these lines onto the other side of the peghead
using a square and then the sliding bevel and knife to mark them.
If done properly they should match up perfectly
with the v you marked on the other side of the peghead.
The proper layout of this joint is critical,
so makes sure it is done right.
To mark out the male part of the joint
measure a skoshe more than 40 mm from the edge of the neck blank.
This gives you room to adjust the joint if necessary.
Scribe a line across the neck blank at this point.
How thick your neck blank is will determine how large an angle
you can use on the peghead.
For a 25mm thick neck blank
an angle of about eight and a half degrees works well.
Use a protractor to set this angle on your sliding bevel
then use it to scribe this angle down the edge of the neck blank.
It should begin at the line that you scribed across the face of the neck blank
at a skoshe more than 40mm.
Scribe this line all the way around the neck blank.
With the neck blank fretboard side up,
measure exactly 40mm from the line that goes across the neck blank
and mark this at the center point of the neck blank.
Use the sliding bevel to copy the same angle that you put on the peghead.
If you use two sliding bevels you will not need to reset this angle again
after using your sliding bevel to mark the eight and a half degree angle.
Compare the layout of both the male and female parts
to make sure they are exactly the same width and length.
Once again, correct layout is critical to the correct execution of this joint.
After verifying your measurements are correct
transfer all these measurements to the other side of the neck blank.
Remember to always reference the same edge of your neck blank.
Now that the layout is done we can begin to remove the waste.
Bill uses a miter saw to remove the shoulders of the male part.
Use the sliding bevel to set your miter gauge to the correct angle.
Mark the place where the width of the V hits the shoulder line
on both sides of the neck blank so that you don’t cut too far into the neck blank.
Make the first 8 and ½ degree shoulder cut just a skoshe forward of you line.
You can then sneak up on it.
This allows you to adjust the angle if you needed to before arriving at your line.
Once again use your sliding bevel to adjust the angle
and then cut the other side of the neck blank the same way as you did before
by making a test cut to check your angle and then sneaking up on your line.
Now use a bandsaw to cut the male part of the V.
Remember you have an angle on the shoulders so be careful not to cut into them.
When making the cut go just outside of your line.
This is what the roughed out male portion looks like.
Now use a bandsaw to cut out the female portion of the joint,
leaving the lines when making the cut.
Now use a chisel to slowing remove material up to the line.
Notice how Bill is working on the female part of the joint first.
Do this on both sides of the peghead and do not undercut the inside of the joint
like you would on a traditional dovetail joint.
By now you are beginning to realize how important the layout of this joint is.
After taking the material down to the lines on both sides of the peghead,
the middle is still proud.
Now slowly remove this material until it is flat.
Work slowly and carefully with a sharp chisel.
Check your progress with a square as you work
and when you are done to make sure you are indeed square with the face of the peghead.
Now use your chisel to begin removing the waste from the male part of the joint.
After cleaning up the shoulders you can then begin working on the face of the V.
Just like before you want to slowly work your way up to the line.
Do this on the right and left side of the joint and from both sides of the peghead.
Just like before, the center part also needs to be brought down
flush with the edges so that the left and right faces of the V are flat.
Once this is done you can place the female part over the male part
and see just how good a fit you got and begin fine tuning the joint.
The trick now is to know where to remove material to make the joint tight.
Bill places some water in the female part of the joint and then presses the joint together.
He then separates the two pieces.
You can clearly see the moisture on the male part of the joint.
The places that are wet are the areas you want to remove to get a tighter joint.
You also need to check the gap between the shoulders.
In this case a little more material needs to be removed
from the right side of the male V
in order to make the gap at the shoulders exactly the same.
Spend some quality time with your chisel
removing these wet areas and then check the fit again.
Rinse and repeat until you get a nice tight fit.
This could take you several minutes or several hours.
If it takes you several days then perhaps you should use a different joint.
When the joint is ready, apply glue
and use a little creativity on your bench to glue the joint together.
After dry time, a few passes with a handplane
to level the joint and you are done.
The peghead is then thicknessed from the back side.
The V joint can be a difficult joint to execute
but Bill sure does make it look easy.
Hopefully with the information in this video
you can also show off your craftsmanship
by using the V joint on your guitars.