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This may be a dumb question but is something I am going to have to address in the near future on my first guitar. I'm 95% handtool woodworker but think that a router is def the way to go for the binding rabbet. Im concerned about the bottom of the rabbet being square to the sides as well as getting a consistent depth of cut due to radius of the plates. Im missing something in understanding the Cumpiano method where he just kind of free hands the router around. How is he getting a square bottom and a consistent depth? Also with some of the jigs that hold a router square (Fleishman design), what is giving you a consistent depth when the router is floating above the body? What is registering the depth on this type of setup?

Im sure there is something simple I'm missing about these methods but being a hand tool guy I'm just not seeing it.

One last question, what are people's opinions on the dremel attachment for routing this channel? StewMac sells one and there is another version out there similar.
http://www.stewmac.com/shop/Bindings,_trim/Tools_for_Binding/Binding_Router_Guide.html

A little donut on the bottom of the jig keeps the depth constant.

Kevin Looker

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I'm not a luthier.
I'm just a guy who builds guitars in his basement.
It's better than playing golf.

the donut is the key as well as positive location and position .

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John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

The size of the donut is important, too. It needs to be wide enough to provide a stable foundation (mine is about 1/8" and works well for me) but not so wide that it alters the depth of the cut when routing the back which has more radius.

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Good judgement comes from experience. Experience comes from poor judgement.

This looks pretty cool: http://www.kennethmichaelguitars.com/bi ... chine.html

I've been using the old hand held version that they now disavow and have been getting great results.

I've been thinking about getting this: http://luthiertool.com/binding%20cutter.html

It's infinitely variable which comes in handy as I make my own bindings, and have bought premade bindings that didn't measure exactly what they were supposed to (which is why I started making my own.)

It's similar to the handheld wooden one I already use so I'm used to the movements.

These all register off the side so the binding channel is not tipped.

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Old growth, shmold growth!

Anthony,
I am going through this myself, so you are right to ask now before you start cutting! My first attempt with a Dremmel used this jig from Stew Mac. It had some serious limitations. The base reached too far onto the top and back, resulting in channels that had decent depth along the sides, but so much runnout that I ended up cutting a lot of the channels by hand. On one end of the guitar, the bit wouldn't even touch the side.

I got my bindings installed, sanded them flush, and the result was not so good. In some places they were simply too thin. I had to start all over, make a new jig, rout those off and try again.

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Phil

http://www.oleninstruments.com

"Those who tilt at windmills are only considered insane by those who can't see the dragon."

I already had the Stew Mac base for the Dremmel, it works great for inlay pocket routing. And, I like the fine tune adjustment for depth of cut. So I found a video on the net about a router tower someone made. (I'd post a link, but have no idea how. Be glad to, if someone will tell me.)

I bought drawer glides, and made it out of scraps. I used the Stew Mac router base, made my version of the donut others have mentioned and attached it with double stick tape. To locate on the sides, I used a pin and bearing I had, the wood parts are dogwood so they took the screw thread taps fine. But I had a problem with it.

Here is my first iteration of the router tower.

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Phil

http://www.oleninstruments.com

"Those who tilt at windmills are only considered insane by those who can't see the dragon."

OK, one more. The problem I had with this setup was how far away from the router bit the bearing touched the sides. As it turned out, these being my first two, the sides were not as perfectly straight/square/whatever. They were bent freehand, and assembled without molds. No big deal, at least I don't think so, you can't see it. But it was just enough to throw off the channel routing.

So, I made another bottom depth indicator. This one is wood. The goal was to get the two contact points where the jig touched the guitar to be as close to the bit as possible. This takes the majority of the tolerances out of it.

I am just now scraping down the new bindings I installed after using this jig, and it seems to have worked well. If youd' like, pm me with your e-mail address and I'll send you the video link of the design I copied, and also more photos if you are interested.

Don't know about others, but so far on my first two, binding has given me the most trouble by far!

Good luck!

The router in the jig is fixed vertically, so leaning is taken care of. It is supported vertically by rubber bands so it slides up and down easily, and does a good job of making what seems to be a pretty consistent cut.

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Phil

http://www.oleninstruments.com

"Those who tilt at windmills are only considered insane by those who can't see the dragon."

The hand held device auto corrects that. Slight learning curve, but no problem after that. Cutaways can be a problem if they're super tight but your average Florentine or Venetian cutaway presents no problem.

No matter what system you use good hand skills with a purfling cutter or chisel come on handy at times.

That being said, I really like the system you came up with. The "tower" machines I've seen all rely on the bearing/cutter combination, which I don't like because I make my own bindings so standard sizes don't always work and it seems arduous to me to use tape to fine tune the depths.

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Old growth, shmold growth!

I'm having a hard time picturing in my mind how that doughnut does anything to help the situation.

But it's been a long night and the coffee is brewing.

FWIW I just rout it out and clean the edge with a chisel. The angle made is not really that big (mostly on the back) and a few passes seems to take it right out.

Like Todd I think I tried every contraption out there. The key to binding channels is control of the cutter . Hand held units rely on your hand skill set. This is a wide variable. The dremel is fine for simple tasks and I have used one on my first 2 guitars and it shows. Like Todd I gravitated to units that can control the variables.
My favorite is the unit that holds the cutter perpendicular to the word surface and have a carriage to hold the body. The reason you need both is that there is nothing square on the guitar. The geometry of the body has few points that are square so using a carriage you can adjust the sides to be parallel to the cutter.
This helps control the position of cutter in relation to the sides. The donut is the part that controls the cutter in relation to the geometry of the top and back. I have seen many donut designs and the one that works the best is the cutter with a minimum flat area . You want to locate on as few points as possible . Without the donut to control the vertical position the cutter will rise and fall . Being as consistent on location will allow the channel to be the same in the X and Y planes. I also like to set the binding and purfling so that the end result has the binding just a touch under the plane of the sides. You will have a better result of the binding by sanding to the binding rather than scraping binding to the sides.
Of all the building processes , this is one of the hardest to master for that fit and finish we all want.
I use 3 router sets , LMI Stew Mac and Grizzly. Between them and using some copper foil tape I can get the control I need.
Lets face it you can learn to do this with a pocket knife but few have that amount of hand skill . Learning to read your chips and listen to the cutter also helps. Using climb and rout cuts , all this comes from experience and technique. Also no matter how good the device , you need shape tools and patience.

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John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

I do it by hand and it's the last part of the build I'd go power tools, even if it is a tedious job; cutting takes me about 1-2 hours per quarter (depends on wood hardness). If the doming is strong and you get a bottom slope, it only takes a few minutes to relieve with a very sharp chisel.

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Build log

Todd I've seen shots of your binding work somewhere, beautiful stuff! However, I don't have your large shop space and power tool set up.

I get good results too, I believe, tell me what you think of my binding job. Takes me 15 minutes to set the depth and height to the binding and go around the top twice for binding and purfling, and it fits perfect with no gaps. It's quite easy to master, and I only had to buy the one spiral downcut router bit, no bearings! ($24 vs $200-$300 for a full bearing set, and the spiral bit cuts cleaner longer, and when the straight cutters get dull, the blow out large chunks from the side, spiral bits just get fuzzy).

I have the Ridgid brand laminate trimmer and have found it to be quite a satisfactory tool, although I was looking at the DeWalt last night.

I just did this with my crappy wood handheld unit a few days ago, it cost me $45, although I'm sure I could have made it myself. Fast and easy to use.

In the side shot you can see the glue where I still need to scrape it, but the binding is already perfectly flush, even in the middle of ta tight curve at a downward slope, all I have to do is scrape the glue off. (BTW the units that hold the cutter square actually cut a CURVED bottom shelf! If the cutter rides along the slope, the bottom is flat....)

So anyone who says that a particular technique is prone to gaps issues or whatnot is mistaken, it's not the technique, it's the individual execution of the technique. I've seen gaps and binding issues too, from some high end hand builders, but it's impossible to say what kind of technique they used from looking at it, but it makes no sense to me to assume that if the result is crappy, it must have been done by hand.

For those with space and money considerations, it's a good option.

A favorite quote of mine, You can always work with precision, if you are precise. I hear one member even framed it and put it on his workshop wall.....

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Old growth, shmold growth!

So if you do it by hand (which would be my preference) what are you using to create your gauge lines? Obviously my wheel style marking gauges aren't going to work. I can see and understand how one of these gauges would create a consistent line around the top and back registering off the sides but how would it create consistent and square line around the sides? BTW, I consider my hand skills to be moderately good. I am also a bit of a perfectionist and will spend as long as needed to get some perfect, which can sometimes be a problem if I need to be efficient.

The older non-adjustable version of that thing actually worked pretty well, especially if used with a piloted bit. It's almost like a power gramil. The main problem is that it will ride shallow in tight waists. The new version with the ball bearings looks like it would be hard to use, as there isn't really anything to grab onto and force against the sides. AFAIK the old model is extinct, unless someone has a used one for sale.

Since no one else has really mentioned it, the obvious middle ground is to make a slightly angled plate to attach to the bottom of your laminate trimmer (or dremel base). You'll need a different one for the top and back. This won't provide perfect results, but it will be much closer than simply going around with a flat bottom router. Robbie O'Brien describes this method in his DVD, IIRC.

I understand the recommendations for various jigs and tooling, but it seems to be that doing this in a more old fashioned way would be good for honing hand skills - important for a new builder.

So you don't think the table on a titemark style gauge will be too large on a radiused back to get a square bottom? Maybe you're just marking the line and chiseling the square bottom. But I have a large scoring blade on my Titemark that I use for paring small areas like the shoulder of shallow rabbets. Unfortunately this method will probably not work when registering off the back plate.



So the old version of this jig isn't available? That's unfortunate. I would think this would work much better than the StewMac version and is the option I was looking at. But as you pointed out I couldn't come up with a source.

Actually it was Stew Mac that sold the old version. They stopped when they came up with the newer version with the adjuster. Maybe you could call them and see if they still have a few knocking around.

Correction: though stewmac no longer sells it, it's available here: http://parts.siminoff.net/binding-routi ... tools.aspx

I use 2 Schneider gramils for all the scoring, plus actual stock removal.
First I do is cut the top or soundboard material off the binding channel by using the gramil aggressively down to the sides. Most of the soundboard just falls off, on the back I usually help it with a chisel. Then I just score the binding depth and use the chisel (in the same plane as the soundboard) to remove most of the side material, just shy from the scored line. Then I use the gramils with repeated passes, the sides leftover is just a couple tenths of a mm thick so it flies off easily, and the second gramil cleans off the other side. This usually results in a very clean corner (or even more as the blade can cut a little deeper than needed) so I never have to round the inside edge of the binding. Then if needed any possible slope on the bottom can be removed by chisel.
Then I score for top purfling. The first few passes need to be very very light and you need to always look that the gramil arm is perpendicular to an imaginary tangent to whatever curve you work on, otherwise you can get a wider cut and tearout. Once the cut is noticeably a cut and not just a score, I use the chisel to remove some of the wood and then score again etc.

The default blade in the Schneider has a very short bevel. This makes the cut very smooth in all directions, but it gains depth slowly and once the depth exceeds the bevel, you will get tearout and widening, so often I switch to a different blade which is only 1mm thick instead of 1.5 and has a noticeably longer bevel, I find this works better in some cases.

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Build log

I have a few different types of purfling cutter, the Sloane type and a few home made versions. I no longer use any of them but came up with this idea:



Pretty much the next step along the popsicle circle cutter. I merely mark with these with the exception of the softer soundboard. Once the mark is formed then a normal scalpel or exacto knife is used to deepen the cut. None of that fiddling around setting the cutter distance.

My vote is the style of binding jig like being sold by Josh at Canadian Luthier supply. I've used this type before, and done the various other methods, and found this to be the most effective and takes up very little space in the shop. I have the one from Josh and the quality is second to none. He is a sponsor at the top.

http://www.canadianluthiersupply.com/pr ... inding-jig

My two cents.

My preferred method now is the Williams/Fleishman jig, but, on my last project, my jig wasn't working smoothly, so I switched to using my old Stew-Mac attachment (the original one, like the Siminoff one --- my set had two attachments, for a total of 4 cutting depths --- I think Siminoff's has only one attachment w/2 depths). It works well, if you know how to use it (I did all my first few guitars with it and prefer it to their present model). It does cause the wood to smoke a little bit (!!!), but I just did a second pass and ended up with channels just as clean as with my Williams jig. So, in a pinch, it's fine --- just took a little longer. I like the older model because you just press the guide with your thumb against the side, and that ensures the cut will be parallel to the side. (I could never keep the cutter parallel with their present one with the roller.) Here are some photos of me using it on my latest project: http://home.comcast.net/~kathymatsushit ... iss13.html

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Kathy Matsushita
San Jose, CA USA
http://theamateurluthier.com
Facebook: https://www.facebook.com/kathy.matsushita

I can totally see my thumb slipping into that space and getting routed.
At least, with MY luck.
As a matter of fact, it's amazing I actually took up something as dangerous as luthiery.

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Old growth, shmold growth!

Ha! You're the second person who's said that after seeing that photo --- really, there is absolutely no danger of that happening, because both the Dremel (actually, it's a Black & Decker RTX) and the guide are being pressed down firmly as I rout the channel, and my left hand fingers are wrapped around the opposite edge of the side, for further support. (And, the Bandaid has nothing to do with the Dremel usage --- I think I had the Bandaid on just to cover where I had removed a splinter!!!) The only drawback is that the aluminum guide does get a little bit hot as you use it, so you need to rout just a short length at a time....

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Kathy Matsushita
San Jose, CA USA
http://theamateurluthier.com
Facebook: https://www.facebook.com/kathy.matsushita

I would route my finger either at the point of pressing the guide to the side or as I was lifting off. My thumb or some other finger would just magically find it's way there.

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Old growth, shmold growth!

This is my trash find! An old Dell monitor stand with counter balance spring for the weight! It's very stiff and works great. I did remove one of the springs to give the proper fall. Falls smooth and slow. These stands are made with very good ball bearing guides and I use the cover to keep dust out! Not bad for being free!