A Lost Art
March 19, 2007
Binding has always added a higher perceived value and rightfully so, as it is a pain to do well. The cost of the material is only a few dollars compared to lengthy detail time required with plastic bindings. In this article I hope to shed some light on it for those who dare to try it for themselves.
Cutting the binding channel can be done in a number of ways using Dremel tools, table routers or, as I use, an inverted laminate trim router mounted to a slide gizmo.
The first thing with binding is to make sure your material has a flat bottom, as most have a rounded edge from injection mold casting or sheer cutting. What I have done is made a small “binding bowl.” You simply coil the binding into the dish, flip it upside down and sand it flat on a flat surface. I use an old 80 grit sanding belt taped down to a workbench. A few good swipes and you will see the binding dull where it’s been sanded and remain glossy on areas that still need more sanding. This assures us we won’t have any gaps at the bottom of our channel route.
Next we need to prep the body. I tape off the sides of the body to keep glue from impregnating the wood pores, allowing us to keep our work clean. Other tools we will need for the gig is a heat gun and a pair of work gloves to keep us from burning our hands. The actual binding I use comes from Stew Mac (stewmac.com). What I look for in binding plastics is a material that will melt a bit when hit with acetone.
Even making the binding glue is a bit of a trade secret that I will share with you. Many places sell “Duco” or similar plastic cements in small tubes. This stuff works fine, but is rather costly. For my own recipe, I grab a can of PVC Glue from Home Depot, Low VOC clear. Fill a solventfriendly plastic squirt bottle roughly half full with this glue, add another 25% of acetone, then using scrap pieces of my Stew Mac crème binding cut it into small pieces, fill the bottle the rest of the way and stir until it all breaks down. This may take 24 hours and a lot of stirring to get it right. You can make white, tortoise or moto binding as long as you find the right plastics that dissolve, which are usually PVC or nitrate-based plastics. Be careful; nitrate plastics can flame up with a heat gun where PVC is very forgiving and can be reheated over and over until you have your final desired shape.
What we want to do is pre-shape the binding, so when we glue it in place it happens fast and any minor voids are filled with our colored glue, which also attacks and softens the binding when being applied.
Using a quick clamp and a few pieces of tape I position the binding around the lower bout of the guitar. The best tape for this is a packaging-style tape that has cloth threads running through it; this allows a great amount of pressure without breaking our tape. Heat isn’t needed for the lower bout, but we need the binding in place to be able to bend our horn areas. Slowly bend each horn area until you have your final fit, just be gentle to avoid kinks and bends. Once it’s all bent we can glue it in place. Don’t remove the temporary tape until you’re ready to glue that section so your bend doesn’t shift. I break up gluing into 4 sections. First the lower bass bout, second the bass horn, third the lower treble bout and last the treble horn. Press firmly and squeegee the excess out with your fingers. Binding takes about 48 hours to flash off, and you may hit soft spots that need to cure longer. Once cured, remove tape, scrape and sand until all is flush.