Tip, Techniques & Tools

My Binding Jig

Don Williams

Over a year ago, I started to build a binding jig invented by Harry Fleischman, that he printed plans for in an issue of American Lutherie.  It was a stroke of genious in my estimation. It was virtually a fool-proof way of cutting binding and purfling channels.  However, I was concerned about the motion of the fixture being a bit too awkward for me, (or perhaps it was me that was too awkward to use it...) and immediately I thought back to my days as a mechanical designer, and thought that linear motion might make a good improvement to the design. I knew there had to be a way of making the motion of the unit more direct and smooth. I spent a few years back in the '90's as a kitchen designer, and so my natural thought was to use a heavy duty, full-extension drawer glide to get the motion I wanted. That took care of the extending linear motion, and a lazy susan base would round out the unit by giving it all the lateral movement it would need to move the arm around the guitar.
The parallelogram concept Harry came up with was brilliant, and needed no change, except that I wanted to use materials that would be easier to work with.
Since so many people have asked me for plans or instructions for building this jig, I've decided to put instructions and some basic dimensions here on this site.....so here it is.

Building the Jig 

Plans for the jig are available on ebay.

Parts 

First, start with selecting the drawer glides. I used a set of 22" Accuride Heavy-duty, full-extension, self-closing glides from Woodcraft.   You can get them elsewhere, but I have a Woodcraft sore near me, so they were a logical choice.  I also bought their 12" heavy-duty lazy susan bearing while I was there. If you have the opportunity, check their supply of these and pick the one that has the least slop in it by pulling the plates apart. You'll see what I mean, some have a tighter construction than others, and since you want your jig to be as free from slop as possible, grab the best one you can.
You'll need to measure the thickness of the drawer glides. The shop spec says 1/2", but mine were really 9/16".  This is important when it comes to making the drawer and drawer box assemblies. You'll also need a 12" square sheet of 1/4" phenolic, which is a great material for making jigs.  This will be used for the plates in the Parallelogram section, as well as a new base for the laminate trimmer.
A sheet of 3/4" baltic birch plywood will be needed for constructing the jig.
You will need some 3/4" & 1-1/2" sheetrock screws for assembly.
You will need (4) 1/4" x 3" bolts, with (2) washers each, and nuts.
You'll also need a small amount of some solid wood, maple, birch, or similar to make the parallelogram arms and the vertical piece to hold the laminate trimmer base to the parallelogam.

The Laminate Trimmer / Parallelogram Assembly

I use a Bosch laminate trimmer. I removed the plastic base for it, to accomodate a new base made of 1/4" phenolic, 2 7/8" x 5". This new base screws into the vertical maple piece that is held between the side phenolic pieces of the parallelogram.  The size of the vertical maple block is 3/4" x 2 7/8"w x 4.75"h.

The bottom of the new laminate trimmer base will also get a disc made from UHMW plastic (Ultra High Molecular Weight).  It needs to be fashioned such that there is a thin donut, 3/16" or so that will ride the top and back of the guitar as the cutter is working.  It is necessary to have this as small as possible to minimize error when cutting the area of the upper bout on the back.

**Notice there are two sets of screws holding the vertical maple plate to the phenolic plate.**
**DO NOT drill the holes and secure both sets of screws at this time.**
**You will want to adjust the angle of the trimmer perpendicular to the workbench once the whole jig is assembled.**

The maple pieces that make the parallelogram arms are 3/4" x 5 5/8"l.  The width of these is narrower than the vertical maple piece by the thickness of two 1/4" i.d. nylon washers, available at your local hardware store.  These provide a low-friction action in the parallelogram. The 1/4" phenolic plates for the parallelogram are 2.5" x 5".  I drilled all four of them exactly the same on my drill press. Drill through the maple pieces to accomodate 1/4" bolts to hold the phenolic and maple together. Tighten the bolts just enough to hold the whole thing together securely, but allowing the joints to move with little effort.

The Drawer Assembly

Here's where you'll start cutting up the 3/4" baltic birch plywood. Great, stable stuff. Not cheap, but very stable and strong.  You'll want to plan on making the drawer so that it fits snugly between the parallelogram plates.  Mine ended up 2.5" high x 2.875" wide x 24" long. It sticks out 2" past the drawer box.  Here's where measuring the drawer glide thickness comes into play. The box needs to be wider than the drawer by the thickness of  the two drawer glides. Then all you do is close up the box and mount the glides.

The Carriage Assembly

Now, onto the carriage. The picture should be self-explanatory. You just make your heights and shape adjustable everywhere.  Plywood everything. I used cork for lining the contact areas.

Making the Base

After you have a carriage assembled, you can tackle the overall height of the jig fixture. Why now? because you'll want to load a guitar in there nd measure the height of it, and plan to have the extending drawer arm well above the guitar, or BAM! you'll smack the thing into the guitar side.  Know what I mean? The height of the drawer over the workbench will end up around 11".
I used 12" x 12" pieces of baltic birch ply for the two pieces for mounting the lazy susan bearing unit. Instructions for mounting the bearing are located here on the Woodcraft site.  You've accounted for about 2" of the height of the base unit, now all you have to do is make a plywood box that can easily be screwed to the lazy susan section, and the Drawer Box section. It will need to be at least 9" high. I made this section 9" high, 12" long, and as wide as the  drawer box, which was around 5.5" wide. You'll want to reverse-engineer into that number before cutting the wood. If you make the drawer box first,  it should be easy enough to arrive at the final number.
Lastly, once the whole unit is assemble, it is time to adjust the angle of the trimmer assembly, and drill the holes in the vertical maple block to secure the unit into position.

Using the Jig

I carefully mount the guitar body into the Carriage, and adjust the height of the four levelers so that the sides are perpendicular to the bench.  A good 8" machinist’s square is perfect to aid you with this task.  A very important step is to secure the the jig to your bench. I use sheetrock screws. This is important to counterbalance the extended arm, and provide stability of the unit so it keeps the router bit parallel to the sides.  Once the guitar is secure in the Carriage, and you have done test cuts on some scrap wood with the laminate trimmer, you can start to cut the channels. Usually, I run the trimmer around the top starting at the neck joint, moving counter-clockwise.  I use the StewMac bearing set for some cuts, and the LMI bearing set for others.
Eventually, I'll have enough sets and trimmers to just swap trimmers in the jig to cut for different operations without adjusting the bits.
In a factory environment, you could line up several guitar bodies in a circular pattern around the unit and route all the binding channels at the same time, moving from one body to another.

Variation by Alan Carruth

Alan's variation on the binding jig is mounted on the wall to preserve counter space. From Alan:

Basically, what I did was to put a pair of drawer glides up on the wall with a piece of heavy plywood attached to them.  An arm was cantilevered off that,  about 6" off the bench top, and it carries another set of drawer glides, with another piece of plywood screwed to them. A short set of vertical glides mounted to that carries the router base. It does about as good a job of holding the router vertical as the lazy Susan, and the router and arm are not over the bench top in the 'retracted' position. About the only 'tricky' part was that I attached the upper glide on the wall to the top surface of a section of 2X, that was jointed off nice and straight. That way the sideways force of the cantilever is not trying to pull the guts of the drawer glide apart. I thought about this rig for a year or more, and then it only took a morning or so to actually put it together once I got the hardware.

Here are a couple of pictures.