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Just a quick question about routing the binding channel. I have read that some like to cut the binding channel slightly deeper than the thickness of the binding and scrape and sand the sides flush and others prefer to undercut the channel slightly and scrape the binding flush. I was just wanting some feedback on what everyone does here and if you undercut or overcut, by how much? Thanks

I under cut the channel and scrap the bindings. Once by accident I did it the other way, and paid dearly with elbow grease while scraping down the SIDES to meet the bindings.

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Lance@LuthiersForum.com

I try to get them as flush as possible without over cutting the channels (ala Lance's problem).

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

I like to cut my binding channels about 0.020" shallow of the binding thickness. E.g., I'll thickness the binding to 0.100" and cut the channel to 0.080". This usually works pretty well with woods that bend fairly easily, especially when installing the binding with purfling.

I install purfling on the top, back, and sides, and I stairstep the cuts on the top and back, so it is pretty much necessary that I get the purfling channel cut right on the money. To me, that has been the bigger challenge.

Best,

Michael

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Live to Play, Play to Live

That's what I thought, but I had read on Charles Hoffman's website and a couple of other places that they like to slightly overcut. His reasoning is this:

"I size them to cut about .010 larger than the material being glued in. This allows for a small amount of sanding and scraping of the side without reducing the size of the binding. I have always felt that binding is one of the most important cosmetic elements on a guitar and if the binding is thin in some areas it will be immediately obvious and reflect badly on the instrument."

I'm asking because I am preparing to order some pilot bearings to cut the binding channels and I noticed that the Stewmac bearings have an extra .012" built in for swelling of the binding. Since I'm using CA which doesn't usually cause swelling this seems unnecessary, but the bearings at Stewmac are half the price of the bearings at LMII. And yes I know that Tracy sells the entire set for $150, but I don't have $150 to spend right now. I was just going to get the bearings to cut my current binding schemes. Thanks.

I too under cut but by only .005-.010. I cut the purf ledge first then the binding ledge. This insures a good tight fit on the purf and leaves just a bit to scrape flush. I once tried leaving the binding .020 proud and was very disapointed in the finish thickness of the finished binding. Also I find that wood binding swells a bit when glued up so a .005-.010 proud dry fit wil leave a .008-.013 glued fit with most wood bindings

I add scotch tape to the nearest bearing size to get it just as I want it. this is not real eazy to do and keep a concentric thickness but with a little pracice and a razor blade I have gotten pretty good at it.MichaelP38586.4924652778

As Michael..I always cut the perfling channel first. Then For the binding cut I used pinstripe masking tape on the roller bearing to lessen the depth of the channel just a bit which gives you a minimal amount of scraping (for plastic binding)of the binding and keeps the binding thickness consistant. Make sure you wind the masking tape in the direction of the rotation of the laminant trimmer or router. Otherwise, your masking tape will start unwinding. Always make test cuts on a scrap piece first..(Purfling and Binding)then test your binding and purfling fit...add or remove tape to adjust for a good fit. The masking tape will flatten out as you use this process so, make your test cuts using pressure on the bearing to insure the tape is well flattened and secure before making the "Real Cut" on your guitar. You may have to adjust for this process a couple of times to get everyting just right but, it is a process that has always worked well for me.Brazilwood38586.5296875

I try to cut my ledge 5-10 thousanths deeper.
I find I get a more consistent binding thickness.

FYI - The Stewmac cutter in the binding bit set is not 1" in diam. but rather .925" in diameter. Therefore the bearings will not create the same binding ledge if used with a 1" cutter. They should probably post that info on their site. Instead of giving the actual diam. it just says .04" or .06" binding ledge. Actually, they will route that quoted size (plus the .012" compensation)if used with the Stewmac bit but if used with a 1" cutter the bearing for the .04" binding ledge would actually cut a .09" ledge. The bearing for the .04" ledge is .82" in diameter. Knowing that, it's still a good deal, you just need to know that the .04" is actually .09" w/ 1" cutter, .06" = .11" ledge and so on...

So, guys, you actually put tape ON the bearing? Why not run a line on the side of the guitar where the bearing, um, bears?

I've used both methods and have a little better luck going slightly deeper with the rabbet. Reason being that it seems to maintain a more consistent final binding thickness as mentioned above.

Carlton,
I used to put tape on the bearing to get the exact size, but since I started selling the rabbett/bearing set, I do this no longer. The reason I used tape on the bearing was because If I had to tape the whole side, it would waste too much tape and usually one piece was not enough. But since I have these bearings, I no longer need tape. Jeremiah, good luck!
Tracy

uses a lot of tape and no chance of getting chips caught under it. I have 1" cutter and a .80, .75. .625, .50, and .375 bearing any thing inbetween I adjust with tape if I needed to adjust more than say .005-.007 I would attach my adjustable pilot bearing guide. I had rather use the bearing on the bit but I can not find them to cut the depth I wish to use so I adjust with tape. I like scotch tape rather than masking. It flattens less due to thinner adhisive layer.

With tape on your bearings, you've got to watch out from the initial "freewheeling" high-RPM spin of the bearing, to the initial touchdown on the wood. That's the most likely place/time you'll lose the tape. (My experience with this comes from furnituremaking, so far.)

When I can afford a set, I'll give Tracy the nod. There's just nothing like having the right tool in hand, especially when the job it is performing is so blatently visible.

Dennis

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Dennis Leahy
Duluth, MN, USA
7th Sense Multimedia

I used to cut the channel .010" deep and then pull the sides in to the binding to be sure that binding wouldn;t get thin in any spots, but a single guitar can wear you out doing it. Now, I cut to the exact depth of the bindings thickness and work the joint between it and the sides as necessary.

Scraping the sides or the bindings take alot of time and energy even when it is only .005" to .010" and my rotator cuff tear made me look to the method of least resistence for myself.

Regards,
Kevin Gallagher/Omega Guitars