Official Luthiers Forum!

I'm hoping you guys can make this a bit easier to understand... I've researched just about every method and tool there is for cutting the binding channel for an archtop and it seems the most reliable way is with a router. I'm one of those hand tool guys so I've never owned a router. What I'm confused about is the table aspect of it. If I want the router to cut my binding channel what do I need? I saw the bits that Stew Mac sells. But how do I set up a table? I watched Benedetto's video and it looks like he has a no-frills table, and two white discs that act as ball bearing guides. Are those available anywhere? Luthiery can be very therapeutic, but this router part of it is only making me need therapy! Can somebody take me step by step through what I need and tell me how it is set up? I guess I'm a bit intimidated by this part because I'm so in the dark about it. I'm almost ready to cut the thing by hand with a purfling cutter and a chisel! But I don't want to mess it up. I remember Benedetto saying that with his set up it's impossible to screw up the box. He said that if you were to feed it to the router in a less than acceptable way it would bump the guitar towards you without taking any chunks with it. Somebody help me! LOL!

can use a wagner safe -t -plane or and tools or whatever to flatten edge of body and then use a lam trimmer and rig to cut the channels like would any other guitar as the donut will ride on that flat area. Several places in archives that note various rigs and binding channel routing techniques.

re-read your own topic here: viewtopic.php?f=10101&t=19126&p=269452#p269452

It has most all the information you need. On the otherhand, I made a router jig based off the ones from Stew Mac and LMI and have done three guitars with it. No problems. Cost me 10 bucks for the drawer slides and I bought the bit from SM.

JD

_________________
Joe

_________________
Joe

Ok please do not attempt using a Wagner safety planer to cut binding channels!!!!!!!!!!

What it all boils down to is finding a way to cut a clean channel that bottom edge is perpendicular to the rim and the inside edge is parallel to the rim while maintaining a precise depth form the top or back

There are several ways to maintain width of the cut. This can be done with a bit and a series of specially sized bearings that each bearing provides a cut width equivalent within a couple thousands to the binding stack width. This system works best with a fixture that mechanically or structurally maintains the center axis of the router parallel to the rim.

No these are not available anyhere the bearing are specially sized diameters to match the cut depth needed for the lutherie industry. The one you will find in a hardware store the bearings are common sized diameters for general wood working.

Another method is to use a router with an adjustable bearing guide. This does the same thing as above by changing the distance from the adjustable bearing edge to cutting edge of the bit. An off take on this is an adjustable 2 bearing guide. The idea behind this is the two bearings ride on the rim thereby maintaining the center axis of the router parallel to the rim.

The deal with the donut on the base of the router is that the top is not a flat surface, so if the full router base rode on the top the bit would be pitched in causing a cut that is not perpendicular or parallel to the rim because the routers center axis would be tilted out at the top and tilted in at the bit. Then add to this that the plane formed by the top is ever changing the amount of tilt would be ever changing. Typically by about 2-5 degrees. With only a small area of the donut riding on the top the foot print of the top has little to no effect on the pitch of the bit.

So the really big thing that is terribly important to know is that no matter what type of jig or fixture you use or even it you are doing this hand held the one thing you must do to have good channels is to maintain the router axis parallel to the rim at all times.

Hope this helps

I am not sure the suggestion was to use the Wagner to cut the channel...I think he meant to create the flat surface that the router donut would ride on. This is fairly common for archtop builders to do. They make sure the first 1/2" edge of the top is flat all the way around the top. Later this will be the area that the recurve is carved into. I have actually also seen pics of Benedetto with a top that was saftey planed prior to installation. I am currently doing this on mine during the rough carve stage.

Archtops are quite difficult to bind without the use of a stationary jig of some sort. I am sure that the double bearing long shaft hand held binding router/jigs could be used successfully, but the top edge of an archie can be much more drastic than a few degrees.

These are not mine, but I think you can see the flat edge that is prepped in advance..

_________________
Joe

Very interesting looking design there! I just checked out a video of the True Channel Binding Routing Jig at Stew Mac's site. They say it can be used on archtops. The demonstration looked pretty good. I'm thinking of going with one of those. Has anybody here tried it yet?

Ok, here is a crude drawing of the table top version. The donut in this case is attached to the bit ala Benedetto. Others have made the donut part of the table. Either work fine.

_________________
Joe

The wood version above in my picture is the same as the true channel for all practical purposes. Mine is made from wood, thiers is aluminum. No different in how it is used.

J

_________________
Joe

Do you want the binding to be a common height all the way around, or in the cutaway area do you want it to get taller in the cutaway area where the arch is?

I run into this on my carved top electrics.

I want the height of the binding to be taller in the cutaway. So... essentially, it is a common height up from the back of the table.

To do this I took a 2'x2' piece of MDF and mounted a stationary arm on it that suspends a lam trimmer over the center of the area. I then use the LMI binding cutter and bearings. I set the cutter to deepest part I want trimmed and just route the perimeter.

This would also work for an archtop, but you would probably need to create a carriage for the archtop to ride in while routing the bindings. A simple MDF "ring" should suffice provided it seated solid.

The system works beautifully.

_________________
Brock Poling
Columbus, Ohio
http://www.polingguitars.com