Robbie O’Brien demonstrates the installation of bindings and purflings.
Bindings and purfling are installed on a guitar to protect the top and back end grain from damage and fluctuations in humidity. They also can add a decorative design element to your guitar. However, a bad binding job can make an otherwise great-looking guitar look really bad in a hurry. It is, therefore, imperative to take your time and do a good job when installing your bindings. Cutting the binding channels in the proper manner will determine the degree of success you will have when installing your bindings. I recommend you refer to my luthier tips du jour video on cutting binding channels in order to increase your chances of satisfactory results when installing your bindings. I also recommend that you start out with simple binding and purfling designs and, as your level of competence increases, you can make more complex designs.
There are many ways and methods for installing bindings and purflings. Here is just one way.
I usually start by installing the bindings and purflings on the top of the guitar. I place the binding in the channel and mark the waist and then the butt end at the centerline. Make sure the binding doesn’t slide off the waistline as you are wrapping it around the lower bout. Mark the waistline and the centerline at the butt end of the guitar for both the left and right binding. The line at the butt end can then be squared down the side of the binding. I then cut off the excess binding at the butt end up close to the line and sand it square up to the line on a disc sander. You could also just very carefully cut it square right at the line. Place the ends of the right and left binding together to check the fit. Make sure they are square. Before I actually begin installing the bindings.
I like to have everything that I’ll need close at hand. I use binding tape but you could also use regular masking tape or blue painter’s tape. A sharp chisel, nippers, and twill tape – this is used to wrap the guitar after the bindings are installed, helping to eliminate gaps while the glue dries. A cheap source for this is twilltape.com. You will also need a bottle of glue. For more on glues suitable for bindings and purflings, watch my luthier tips du jour video on glues. If working alone, I like to place small pieces of binding tape around the work surface so that they are easily accessible during the installation process.
On this guitar, I will be installing a black/white purfling strips.
I start by running a bead of glue in the channel from the end wedge up to just past the centerline at the waist. Then, place the purfling in the channel, temporarily securing it with a piece of tape at the end wedge and at the waist. Now run another bead of glue in the binding channel and use your high-tech glue spreading device to spread the glue in the channel and onto the side of the purfling. Place the binding in the channel, aligning it with the centerline of the end wedge. Place a piece of tape on the binding to secure it. As you tape the binding, be sure to pull it up tight against the top or back and push it down against the sides. This will help eliminate any gaps. Also, be careful to not let your hand slip off the tape and scratch the top with a fingernail. This is especially important with wood like cedar. Some builders even seal the top before binding with a coat of shellac. This will help with glue clean-up and tape removal later. Keep taping off the binding and purfling up to the waist. Now, measure to the center line and mark this on the purfling and binding. Cut these off with nippers. Remember, it doesn’t have to be perfect, as the neck will cover this area. Remember, we stopped the bead of glue just past the waist so now we need to apply more glue-up to the centerline on the neck end of the guitar. Now continue pulling up the binding and purfling and pushing them down as you tape them off. Do the other side of the top exactly the same way. You will need to work quickly depending on the open time of the glue you’re using.
As soon as I finishing binding the guitar, then I wrap the guitar with twill tape. I start at the waist, pulling it tight as I work. Then I make a pass under the guitar and back over the top. Watch carefully as I show the sequence to wrap the lower bout. I do the upper bout in the same fashion. I then go end to end with the twill tape until the guitar is completely wrapped. Usually, about a hundred feet of twill tape is enough to do the job. If you think it’s needed, you can place a clamp at the waist and another at the ends of the guitar to help keep everything tight while the glue dries.
The backside of the guitar is done exactly the same way as the top. The only difference is that on this guitar, there will be no purfling. Also, when cutting the binding to length on the neck end, you must be more precise because some of the binding may not be covered by the heel of the neck. I like using nippers to get close and then a sharp chisel to make a nice square cut. You can also miter this joint. Mitered purflings create another challenge. I like to pre-fit everything before I apply glue. If you have a nice polished back on your chisel, you can easily rotate the chisel and see when the cut is exactly at a 45-degree angle. If you want to miter the side purflings, then you must stop short of the end wedge when cutting the binding channel. You can then use a chisel to cut the miter on the end wedge purfling. Then use the chisel to bring the depth of the binding channel up to the purfling. You must also miter the purfling on the bottom of the binding.
Make sure everything fits nicely before applying glue. Binding a cutaway guitar adds yet another level of difficulty to the whole process. Especially if it is a Florentine cutaway with a complex purfling and binding scheme. In this case, dry fit everything before gluing and keep the miters tight as you work.
Now you can appreciate why I said “keep it simple”. With a little practice, you will become an expert in no time at installing binding and purfling, whether they be simple or complex designs.