Luthier Tips du Jour - Go Bar Decks - O'Brien Guitars

Uploaded by OBrienGuitars on 20.05.2009

A Go-Bar deck is an ancient clamping method that is widely used in lutherie today.
A Go-Bar is a flexible rod used in this centuries-old technique of clamping.
These strong flexible go bars are placed under tension between the top of the go bar deck
and the pieces to be clamped, providing even and constant downward pressure.
Go-Bar clamping is in many ways superior to many modern clamping methods.
It allows fast and efficient clamping for braces, soundboards and backs, among other things, while the glue dries.
Some of the benefits of using the go bar method for clamping include:
It is inexpensive.
You don’t have to invest in a lot of clamps.
The rods can be placed close together and in hard to reach places.
They can be positioned and removed quickly and easily.
A word of caution is in order here though.
Always where safety glasses when working with the go bars.
If one should slip and come loose while using them under pressure,
it is like a room of mousetraps going off all at once. So, be careful.
LMI recently redesigned their go bar deck and sent me one to test.
I was impressed with the simple, functional design they came up with.
The go bar deck came neatly packed in two boxes.
The first box contained the top and bottom of the deck as well as the flexible go bars.
The second box contained the metal rods that support the top and bottom.
I also found what I thought was a set of instructions for putting it together but it was only a packing list.
We all know that real lutheirs don’t need instructions anyway.
If you can’t figure out how to put this thing together perhaps you should reconsider building guitars in the first place.
The first thing you do is place one of the metal rods into the plastic base located on the bottom part of the go bar deck.
It looks like the one I am showing here.
The rod has a small metal rod inserted in it.
Place the rod into plastic piece until it bottoms out and then turn it clockwise about a quarter turn.
This locks it in place.
Do this on all four plastic pieces.
Once all the rods are inserted into the plastic pieces located on the base,
it should look like this.
Now use a 5/8th inch socket and tighten the nut located on the side of the plastic piece.
Do not over tighten it.
Do this on all four plastic pieces.
Next I measured approximately 22 and 1/2 inches or a little over 57 cm
from the base of the go bar deck up one of the metal rods that I just put in the plastic piece on the base.
I marked a line here.
I did this again on the metal rod diagonally across from the first rod I marked.
The LMI go bar deck comes with 4 drill bit stops.
I place one of them on the metal rod and locate it at the line I marked at 22.5 inches
or a little more than 57 cm from the bottom of the go bar deck.
I fix it in place by tightening the set screw with the allen tool provided from LMI.
Repeat this operation for the other metal rod that you marked.
The top of the go bar deck can now be placed on the metals rods.
Align the rods with the holes in the 4 plastic pieces attached to the upper part of the go bar deck.
Push it down until it makes contact with the 2 drill bit stops you placed on 2 of the metals rods.
This maintains the upper part of the go bar deck at the correct height.
It is secured in place by tightening the 4 knobs.
You can now test the height of the upper part of the go bar deck
to make sure you are applying just the right amount of pressure with the flexible go bars.
I checked mine by placing a radius dish in the go bar deck and then a top with braces.
I then placed some of the rubber tipped flexible go bars on the braces to check the tension.
You can adjust the amount of tension applied by the rods by simply moving the stops on the metal rods up or down.
Once this is correct I measured up the metal rod from the top of the go bar deck
another 4 inches or about 10cm and marked a line.
I did this again on the metal rod located diagonally across from this one.
I then placed metal stops at these locations and locked them in place with the allen tool.
This is where the new LMI go bar deck really shines.
When gluing braces to a soundboard or back you need one length of flexible go bar
but when gluing them to the rims you need another length go bar.
Well, by simply loosening the 4 plastic knobs that secure the top of the LMI go bar deck
you can easily slide it up or down on the metal rods.
The stops attached to the rods
place the upper deck at exactly the right location needed to provide the right amount of tension with the go bars.
By retightening the 4 knobs the go bar deck is again ready to use.
I can use the same length go bars instead of having to invest in more go bars with different lengths.
Since their design also doesn’t use threaded rods to hold the top and bottom of the deck together,
I don’t have to adjust the distance between the two by adjusting nuts up or down the threaded rod.
Brilliant! I wish more things in lutherie were this simple!