Luthier Tips du Jour - Manual fret Slotting

Uploaded by OBrienGuitars on 19.11.2009

The LMI Manual Fret Slotting System
makes it easy to precisely slot any fretboard to the exact specs you need.
The most difficult part is setting up the jig when you receive it from LMI.
That is why I have asked my 3 year old shop assistant to read the instructions
and help me put the jig together.
The first thing my shop assistant said to do was to attach the jig to a piece of plywood or MDF.
There are two screws included just for this purpose.
The two plastic washers go on the screw to fill the gap between the jig
and the material you are screwing the jig to.
You could also attach it directly to your bench
but attaching it to a piece of plywood allows me to clamp it to my bench when I need it
and then remove it and put it away when I am not using it.
The backbone of this jig and what gives it its accuracy
is a template that allows you to cut any size scale length with precision.
LMI has a variety of these templates that correspond to the most popular scale lengths available.
Each template has two scales on it.
One scale length on one side of the template
and another closely related scale length on the other side.
Two for the price of one, I like it!
Choose the scale length you desire and place the template in the jig
with that scale length facing towards you.
The indexing pin included with the jig slides into the hole in the side of the jig
and into the notches or slots cut in the side of the template.
You will notice that there are two holes for the pin.
If you are left handed use the left hole and use the right hole if you are right handed.
The fretboard I am going to slot needs to have a flat edge on one side
so I run it across my joiner.
You can also square the edge where the nut goes if you like.
When placing the fretboard in the jig you can push it up against the saw
and start by cutting the first fret slot if you squared up the end of the board where the nut goes.
Some folks prefer to cut the nut slot first a little bit in from the end of the fretboard.
In this case it is not necessary to square up the end of the board as this will be done later.
For this fretboard I will be making the first cut about an inch in from the end of the fretboard.
With the fretboard in place in the jig, mark the other end where it hits the template.
A piece of tape on the template makes it easy to see the line.
Now remove the template and fretboard from the jig.
The fretboard gets attached to the template with a couple pieces of double sided tape.
It is important the fretboard edge that you ran across the joiner
be flush with the edge of the template.
Align the end of the fretboard with your pencil mark
so that it is placed back on the template
in approximately the same position as it was before in the jig.
Also don’t use too much tape.
You have to be able to remove it later.
The fretboard and template can now be placed back in the jig
with the fretboard on top.
The pin is inserted into the first slot of the template.
This slot represents where the end of the fretboard hits the nut of the guitar.
The edge of the fretboard and template must be flush against the front of the jig.
You can then tighten the hold down screw that holds the fretboard and template in place.
Next place the saw in to the jig like I am showing here.
Use the alan tool to adjust the saw guides
so that the saw blade is just resting on top of the fretboard.
You also want the brass part of the saw
to be resting on the tops of the four bearings.
To set the depth of cut use the Alan tool
to turn the four adjustment screws in a clockwise direction.
This lowers the guide blocks and bearings.
Each complete turn of the wrench equals a depth of .050 .
So, if you want a depth of .150
you will need to turn each screw a total of three complete revolutions.
Now tighten the two adjustment screws that add tension to the guide blocks.
After clamping the jig to the workbench it is ready to use.
Make sure that the edge of the fretboard is flush with the front part of the jig
and securely held in place by the hold down screw.
Go ahead and make the first cut.
Let the saw do the work and try not to flex or rock the blade as you cut.
Keep the saw as level as possible.
This first cut is to mark where the nut meets the end of the fretboard.
Once you have cut the slot to the depth you set earlier,
release the hold down screw and then remove the pin.
You will need to slightly lift the saw out of the cut you just made.
Slide the fretboard and template into the jig
so that the pin is now inserted into the second notch of the template.
Make sure it is flush against the front part of the jig
and then tighten the hold down screw.
The fretboard is far enough into the jig now
that you can probably use both hold down screws.
Once again let the saw do the work as you cut the slot.
Continue these steps until you have cut the number of frets needed for your guitar.
After you are done cutting the fret slots
carefully remove the template and fretboard from the jig,
then carefully remove the fretboard from the template
being careful not to break the template.
You now have a perfectly slotted fretboard and can continue building your guitar.