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hi, im starting to work on my first guitar and after looking over everything I need to do I get most of it but im not sure how to cut the back binding channel. Im not sure because the back has a radius to it unlike the top which the router lays flat. If you had any ideas how to cut it, what to use and techniques on how to do it, I would be thankfull

Hey,

There are a wide variety of binding jigs on the market that are made to handle this problem (I sell one design, the Kett binding jig). Basically you need some kind of jig that will keep the router square to the side when cutting the channel. If you do a quick search for binding jig designs here on the forum you will see samples of a number of different options. There are also several designs you can make yourself that will work with a laminate trimmer. This is usually a lower cost option, which may be preferable if you are starting out. A quality binding jig is money well spent (or time well spent if you build it yourself) as it makes the whole process easy and straight forward.

I'll also mention that unless you are building true flat-top guitars you will need a binding jig to cut the top channel as well. Most steel-string guitars built these days have a slight radius to the top. It is not near as much as the back, but is still enough to keep the binding channel from being cut square.

Josh

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Josh House

Canadian Luthier Supply
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House Guitars - Custom Built Acoustic Instruments.
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Every one has a system they prefer. Mine is this one: http://luthiertool.com/binding%20cutter.html

It's simple, and works. There's a little bit of a learning curve.

I like it because it indexes off the side directly, so it accounts for slight imperfection in the sides and so keeps the channel square to the sides all the time, in a way that sliding cutter carriages can't. (we all strive for perfect side geometries, but sometimes we fall short.) If the sides flare a little it's no problem.

It's infinitely adjustable, which is good for me because I make my own binding.

Also, especially with the backs, if the cutter remains parallel to the ground but is cutting up or downhill, as is the case with an arched back, the round cutter being held obliquely in relation to the side will produce a round bottom, but the hand held device follows the arch and more accurately produces a flat binding channel all around the guitar perimeter.

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Old growth, shmold growth!

It looks like you could trim the overhang and the binding channel all at once wit the williams jig, correct?

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Old growth, shmold growth!

Interesting. I do believe Todd has lost his mind at this point....

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Old growth, shmold growth!

This stuff is way over my head.............................!!!

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A person who has never made a mistake has never made anything!!!

Hey! I didn't say that! You made that up!

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Old growth, shmold growth!

That's because your sides are perfect and immaculate.

Not everybody's are.

But that's okay, I'm not knocking the William's jig.



The height and width are adjustable and can be made to match the binding and purfling exactly.
And I can use a spiral bit.

I don't like the binding/bearing setup. It's not that it's limited per se, it's just not my taste. You have to match the bearing/bit set to the binding as close as possible, and then if they don't match perfectly you have to get creative and shim with tape or some such, and tape is compressable. Also, the straight bits in my experience are more prone to blowing out when they start to get the least bit dull than the spiral bits, and when they wear out they're more expensive to replace.

Of course, you can make your bindings to match, but if you want to buy some commercial binding that's not exact, or make some binding that doesn't fit the usual bit/bearing setup, it requires a little more prep.

All I have to is set it up to whatever I'm using and it fits exactly, all I usually have to do is scrape a little glue off the binding when I'm done.



Yup, that's what I mean, arched like many acoustics.
The round is likely not enough to matter, but I don't have to worry about that at all.



What do you use for that? I'm curious.

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Old growth, shmold growth!

Does the Williams jig register off the side for parallelness to the side, or is it held plumb by it's mechanism and only uses the side as a position reference?

If the side is flared enough that COULD potentially be a problem.

Also you must set it up in the carriage very carefully to avoid problems . If your guitar is tilted, that COULD potentially affect the cut as well.

Did you notice my last quote of yours? I was being playful.

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Old growth, shmold growth!

Again, I'm not poo-pooing the Williams jig. I'm just pointing out that the accuracy depends on two things, how well the machine is made, and how well you adjust your guitar cradle, since essentially the device is held rigid and the instrument is set up around that. If the cradle's off or if there's variability in the sides, IE flare or whatever, the device doesn't conform, but the difference will probably not be enough to notice on the finished product without looking closely.

The handheld device is in fact more unwieldy, requiring goodhand eye coordination as well as a steady hand and more careful technique when compared to the Williams jig, but it registers to and conforms to the side, and accommodates irregularities better, if someone were concerned about that, but side prep is extremely important beforehand as you've pointed out, but it can sit in the cradle however you want and it'll still cut accurately. Once you're past the learning curve it's very smooth. The learning curve for me was one guitar. It also takes up a LOT less space, so for someone like me for whom space is a premium, the Williams jig is extremely impractical.

BTW I don't own a Williams jig but I've seen guitars made using it, as there are quite a few hobbyists around here. The results are definitely as variable as the builder, but obviously, so would the results be with the handheld device.

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Old growth, shmold growth!

I use a William's style jig followed by a quick follow up with a gramil to ensure binding channels are uniform width. Works even where free form building results in far less than perfect side to back/top geometry.

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Aaron Craig

I also have a hand held side registration jig and find it works a treat. I don't have a Williams but it has nothing to due with workmanship or accuracy. It's mainly a case of space and how many big jigs does one have to have to build a few guitars a year.
Tom

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A person who has never made a mistake has never made anything!!!

As Todd points out , it is about controlling the variables. If you are relying on a hand held unit , you have the variability of individual hand skills . The next variable is the ability to locate the cutter.
If the pilot bearing center is not in line with the cutter center you have a variable in the location. The only point that the cutter would be at a correct position is when the work is tangent to the bearing.
The other variable is the parallel to the side and cutter alignment. Even a great jig may need to be adjusted to eliminate that issue. So as you can see the more accurate the jig , the more you can control the variables , the better the outcome. The carriage controls this issue for the tower jigs like the Williams or Rebekke .
When you look at hand skills , this is a wide variable from one person to another.
I agree that shop space and cost are things each has to decide on from and individual point of view. I will say this , cheap is often more costly so choose your tooling wisely . You can make anything work if you have the time and are doing it as a hobby. If you are working for production , then you are looking at cost and time for production .
Complexity of the binding / purfling is also a consideration . A simple binding over say a D45 style takes things into a different zone. The more complex the design the more need for accuracy.

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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

Unwieldy was a bad term.

It just requires more control, but the result is always square to the side and the bottom ledge is always flat. And controlled is certainly not random. Space is certainly a concern in my shop.

I've used both as well, my first binding experiences were almost 16 years ago building Teles, I'd chuck the bearing bit into my router table. Worked great, but the bits wore out fast and would then blow chunks out of the hardwoods I was using.

Then again I was building the guitars out of purpleheart, bubinga, brazilian cherry, etc........

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Old growth, shmold growth!

The Williams may be easier to use and more efficient but I doubt if it is more accurate and effective.
Tom

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A person who has never made a mistake has never made anything!!!

What do you mean by waiver? A ripple?

It has two bearings, one on bottom and one on top right below the cutter, so if there's a ripple the bottom bearing will follow the ripple unless you adjust it to avoid the ripple. That's why side prep is important, as well as good bending and gluing skills, but those are important anyway. I haven't run into that problem.

If it's a flared side, it follows the flare and keeps the binding channel true and parallel to the side. It also rides the arch and keeps the cutter parallel to the top for a true square ledge. Not a huge problem, I know, but I like the idea that my ledge is true.

The registration foot is 3/32, plenty to keep it on top of the guitar.

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Old growth, shmold growth!

I would say so. The trade off for the ease of use and efficiency is the dedicated space, either on the floor, or in storage on the wall or on a shelf. Also the cost of buying and maintaining all the different cutters and bearings.

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Old growth, shmold growth!

I have used about every jig out there for binding. The williams is the best one I have ever used. I can do a complex scheme like a D45 with ease. The best bit set I find is the LMI , I think it has more options than the Stew mac. I also use a combination set from Grizzly for wider and custom stuff.
I will say as hand held units go , Kett is a step up over any hand held I have seen. Find what works for you and use it. Still , you won't get the williams out of my hands.

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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

...then there's the Hallam jig, which came into existence in Garry Hallams shop in the UK after a discussion about Jim Olsen's set up over on 'The Luthier Community'. I was lucky enough to get one of prototypes, or at least from the first batch, and I sure like it better than any other that I've tried (which is most of the ones mentioned in this thread, and then some). It replaced at least two jigs in my shop, as I can use it for both flat and arch top guitars and mandolins. I mounted mine on a board with adjustable brackets to cradle a guitar, and with "French cleats" on the back, so it can be stored on the shop wall when not in use. Set up / break down is very quick and easy with this arrangement.



This just in! Garry now sells them http://www.luthiertools.co.uk/ (I have no financial interest in the enterprise, even though there's a picture from my shop on his web site)

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Rian Gitar og Mandolin

thanks for the heads-up Arnt! do you mean Garry now sells the stuff on his site? - i´ve been wanting one of those since i first put my eyes on said thread at Luthier´s community. besides its pedigree, it´s also the prettier and more elegant binding jig i´ve ever seen.
i still can´t find the jig in his luthiertools site, maybe he´s still baking them?

cheers,
miguel.

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member of the guild of professional dilettantes

Not sure, email him

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Rian Gitar og Mandolin

Just did!

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member of the guild of professional dilettantes