Online Apprentice-
Rout the Binding and Purfling Ledges/Fit and Glue the Bindings

In this lesson we will rout the purfling and binding ledges and fit and glue the bindings and purflings.

Top Binding and Purfling
I use cyano-acrylate(C.A.Glue aka "Super Glue") to install bindings and purflings. I learned about this method from Charles Fox several years ago. It has since been published in "American Lutherie #76" I highly recommend that you read that article. My method is slightly different but the idea is the same.

First thing you need to do is to bend the binding and purfling strips. In this course I used the LMI Universal Binding Machine to cut the soundboard purfling/binding ledge. Be careful not to rout the tail purfling. We will cut that by hand. Measure the width of the bindings and purflings and adjust the cutter. Make a practice cut on some scrap and see how the binding and purfling fit. Adjust the cutter so that there is a perfect fit or 0.005" over hang of the binding. Prior to using the UBM I score the top and sides with the LMI Gramil. This helps prevent any spliting of the wood when routing.

The UBM leaves a nice smooth ledge. I use the LMI Binding Cutter/Bearing Kit which allows you to control the ledge sizes in .010" increments.

Chisel out the excess at the neck. You will have to do this by hand. I usually set the binding in about 1/2".

Seal the soundboard edges and the face with a small brush and some lacquer. This will prevent the cyano-acrylate(C.A.) glue from staining the top.

Bevel the tail purfling and binding. It should stick up above the ledge the same thickness as the side purfling.

Now we are ready to fit the binding and purfling. The first thing I do is fit the binding and purfling to the waist. Then I cut the upper bout end so it fits about 1/2" into the neck/heel joint.

Next is the tail purfling joint bevel. Mark the binding where the tail purfling and side purfling meet. Use the chisel as a mirror cut a 45 degree angle. Cut this bevel so that it is a little bit farther from the line you marked on the binding. That way you can slowly approach the joint until it is perfect by repeating the process.

Check your work frequently until the fit is perfect.

Next thing to do is to cut the binding at the centerline of the tail purfling.

This is a new experimental method that uses clamps. I start at the tail end and work my way around the instrument. I use a pipette and thin CA glue that is wicked into the clamped joint. Glue about a few inches at a time. Wait a few second for the CA to wick into the joint then wipe it off with a towel. Wait a little bit for the glue to cure then clamp the next section. This process is repeated for the rest of the binding and purfling. The photo to the left is how I clamp the waist. I forgot to shoot a photo of me starting at the tail end, but that is where I start. Sequence:tail,lowerbout, waist, upper bout, neck.

Close-up of the waist.

Upper bout.

Close-up of upper bout.

Now we fit the other half of the top binding and purfling. The process is basically the same as above. The only challenge is with fitting the tail purfling joint. Work slowly and approach fitting this joint with care and patients. Remember it is better to have too much wood then not enough. Start by fitting the waist first. Tape it in place, then fit the tail purfling. Once that fits perfectly you can cut the binding and purfling for the neck joint.

When you are done you can scrape the binding and purflings level to the top and sides.

Back Binding and Purfling

I'm going to show you a different method for the back binding and purfling. For the sake of this lesson let's assume that you already cut the white/brown/white purfling veneer strips. The problem now is how are you going to miter them to the back central purfling? You need the three pieces to be glued together. I like to use Weldwood Contact Cement, but any good industrial brand will do.

Lay the six veneer strips on top of a piece of wax paper or plastic sheeting. I use spring clamps to hold everything down. The veneers are clamped at the ends with a small block of scrap wood.

Brush the contact cement with a thin coat the length of the strips. Give it about 15-20 minutes to dry. Then stick one of the brown/Brazilian rosewood veneers to one of the white/maple veneers. Be careful not to touch the other veneers because this contact cement is very strong and once it sticks...IT STICKS! The remaining white/maple veneers will be used after the next step.

Brush contact cement onto the back of the brown/Brazilian two-ply veneer. Wait 15-20 minutes.

Apply the single white/maple veneer to the two-ply veneer. All you need is finger pressure. If you have some minor gaps that do not stick together don't be too concerned, it will be fixed when we glue everything into the binding channel. The contact cement is only temporary. My first guitar, which I still play today after nearly 15 years, is still holding up and the purflings were attached with just contact cement!

Measure the width of the binding and the tri-colored purfling. In this case it measures 0.160".

Rout the back/side purfling channel to the width of the binding/purfling.

Do not rout the section at the tail....

...or at the heel.

Use the gramil and set it to the height of the binding channel.

Then cut the section of the side that was not routed. Do not cut into the purfling!

Do the same with the heel end. You might have to use a chisel to make the cut. Be careful!

Next we need to score the back. Using the gramil, measure the depth then score the line making sure not to cut the purfling.

Use a chisel to pare away the waste.

Measure the thickness of the purfling then use the gramil to cut the end of the back purfling.

It will now look like this.

Use the flat side of the chisel to act like a mirror. When it looks like a 45 degree angle make the cut. Make sure the chisel is sharp!!!!

For the side purfling you can measure it or use this trick. Lay a scrap piece of purfling in the channel then lower the gramil to it and set it.

Square the tail purfling then mitre like the back purfling. Repeat these steps for the heel section of the back.

Fit the binding and purfling. I like to CA glue a half section of the back.

Before gluing make sure your miter joints fit snug.

Once it all fits well go ahead an use the CA technique used for the soundboard purfling and binding. This time you do not need to use sealer because the CA glue will not show up in the hardwood. In fact it makes a great pore filler.

Repeat for the remaining half of the back. Use a scraper to level the binding/purfling.

Use a piece of scrap from the back off-cuts glue the heel cap on.

Shape the heel cap with a scraper and file.

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