Laminating Guitar Sides and Linings
Laminating guitar sides is one of the many of the techniques I use in guitar making that come from my days of furniture making. There are basically two methods guitar makers use to bend sides, steam or heat bending and laminating, and both methods work. And they will work equally well on classical guitars as well as steel string guitars.
I am not the first guy to laminate the sides of the guitar. The old top of the line Rameriz 1A classical guitars had laminated sides. Daniel Friedrich laminates the sides of his guitars as well. There are more now but back when I started doing it these were the only two I knew of. Bending with heat takes time and is fairly inaccurate. Laminating his it beat on both these counts alone. And there are many more advantages. There is more information on the advantages below.
Torres believed that the purpose of the guitar’s sides were simply to hold the to and back apart and had nothing to do with sound production. He made a guitar with paper-maiche sides to prove his point. An optimal set of sides are to be as stiff as possible. They behave much like the rims of a drum. They hold the skin taut and don’t get in the way. That is exactly how your guitar sides should behave.
When I was designing and building furniture I used this method of laminating exclusively to create just about any desired shape. I found it to be very reliable and easily repeatable. I now use this method to make linings and purflings. If done properly this method will produce lasting superior results. I started laminating sides on my second or third guitar. I have not done it any other way since.
Advantages, Demonstration & Details
The Thickness of the Laminations
When laminating wood to create a shape the rule is, more and thinner laminations will produce better results. If you are building guitars using the traditional Spanish method of fitting the sides into slots in the heel, it is best to make the total thickness of your sides slightly bigger than the slot. If you are using the side slot cutting sled with a .100″ wide table saw blade, it is best to make the total thickness of all 3 laminations approximately .115″. This way it will be necessary to trim the sides slightly to produce a tight fit.
The outer layer of wood must be thinned down to between .070″ and .065″. I typically pre-bend the outer layer of to make the process go smoothly. At this thickness it will bend easily without water and there will never be a chance of sanding through. The inner laminations are two pieces of .6mm (.022″) thick veneer.
Wood for Inner Laminations
For laminating guitar sides I find that certain woods work well for the inner laminates. On spruce top instruments I typically use Alaskan yellow cedar, or sitka spruce if I can find some. On a cedar top guitar, pear wood is my wood of choice. Alaskan yellow cedar and pear wood side laminations are available in the store. Before laminating lightly sand the inside surface of the rosewood especially if it has been pre-bent in a side bending machine. Apply the glue evenly, preferably with a roller. Sandwich all the pieces together, place them in the mold with the cauls on top, and apply the clamps starting at the waist.