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Hi All,

Searched the archives, and didn't find anything about how folks address the sharp edge on their bindings... On my first two builds, I just used fine grit sandpaper to lightly knock the razor edge off the outside of the binding. Do any of you actually use a quarter round bit or similar to produce a more predictable contour? Just leave 'em sharp?

Thanks!

--Jaybird

Just use a small rounover bit...

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MK5acoustics.com

I also use a round over bit and clean it with sandpaper. I like a nice round on my binding. It digs into your arm less and it is less likely to chip than a sharp edge. I also prefer the look.

Josh

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Josh House

Canadian Luthier Supply
http://www.canadianluthiersupply.com
https://www.facebook.com/canadianluthiersupply?ref=hl
House Guitars - Custom Built Acoustic Instruments.
http://www.houseguitars.com

Most guitars are much too sharp edged for my taste. I round over the bindings as far as I can without sanding through anything. Rasp for the major wood removal, needle file to smooth out the scratches, and scraper or a little square of 220 sandpaper after that.

I do admit that a single 45 degree chamfer around the edge looks cool (as is often done on violins), but this is one area where I feel form should follow function, and smooth edges are definitely more comfortable. And they do look good too, nice and inviting.

To me, a guitar with round edges and a less glossy finish begs to be played, and one with sharp edges and mirror finish begs to be put in a museum Although satin finish is the equivalent of bug repellant for me... hate that scritchy feel. A thin shellac finish is the best. Shiny but not too shiny, and feels like you're touching the wood rather than a glass shell over it.

I go at them with a file, and shoot for as much as a rounding as possible without hitting the first purfling line. I generally use a second cut cabinet file for this and for work on the neck after I've gotten to where I want to go with a rasp or spokeshave.

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Jim Kirby
kirby@udel.edu

Sounds like French Polishing

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Jim Kirby
kirby@udel.edu

Don't be a chicken. Dig into that purfling just like anything else I aim for the rounding to end at the transition from purfling to soundboard wood. Or with no purfling or just a single veneer line as I sometimes use, round into the soundboard wood too.


Can be But lately I've just been wiping on a few coats and calling it done. You can also French polish until you've got a thicker uber-gloss coat, which does look pretty, but given the lack of durability and difficulty of building it back up seamlessly if it gets scratched or worn, I don't really recommend it. Hence, "thin shellac finish" covers any method of applying it thinly, which looks good, feels good, and is easy to repair

Try rounding the exposed edge of the binding before you put it on, even before you bend it. Don't forget to relieve the inside corner, too. If you use tape to hold the bindings when gluing you'll find you can pull a lot more tension before the tape breaks and if you relieve the inside edge you won't have to pull as hard to get a tight fit, anyway.

After levelling, coarse sandpaper (80 grit) on a hard block takes off the bulk of the edge, following up with finer grades. Takes less time than setting up a router (unless you're tooled up enough to have one permanently set up).

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Trevor Gore, Luthier. Australian hand made acoustic guitars, classical guitars; custom guitar design and build; guitar design instruction.

http://www.goreguitars.com.au

That's pure genius, Trevor. I see where it could make a distinct difference in how much pressure you can achieve with tape.... Can't wait to try that. --J

I use the sharp edge to slice meats and cheeses.

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http://www.CostaGuitars.com
PMoMC

Hey Josh, what bit do you use? Must have a small radius!

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Alain Moisan
Former full time builder of Acoustics, Classicals and Flamencos.
(Now building just for fun!)

I use a 1/8" radius bit and agree with others that it makes the guitar much more pleasant to hold. I also find that rounding over the bindings makes zipflex purfling pop more (as in a good way i.e. stand out - unless of course you hit them with the bit).

Pat

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There are three kinds of people:

Those that make things happen,
those that watch things happen,
and those that wondered what happened.

When you use a round over bit do you also use your binding router jig?

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Alain
_______

Yes.

_________________
There are three kinds of people:

Those that make things happen,
those that watch things happen,
and those that wondered what happened.

A small scraper work fine for me. A little bigger than a flat pick.

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Michael Lloyd

“I was born to ignorance, yes, and lesser poverties ...
I was born to privilege that I did not see ... I didn’t know it, but my way was paved” – John Gorka

That's the biggie. How many of us have been merrily radiusing away and all of a sudden realize we beveled the area at the neck-body junction. That's not all that easy to fix.

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It's not what you don't know that hurts you, it's what you do know that's wrong.

yup, got that T-Shirt

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Steve Smith
"Music is what feelings sound like"

I mark the fingerboard area on the top and go at the rest with a scraper, then sandpaper 150 then 240 grits. I also now round the area where the arm will rest on the top for extra comfort. After doing an armrest bevel I am spoiled so I now break the edge extra in that area, much more comfortable to play.

Fred

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Fred Tellier
http://www.fetellierguitars.com
Facebook page http://www.facebook.com/pages/FE-Tellier-Guitars/163451547003866

I'm pretty sure it is 1/8", like Pat is also using. I use it in a laminate trimmer and I set it a little shallow. It doesn't give me a perfect radius, due to the arch in the top and back, but it gets me close. I finish up with some 150 and 220 by hand.

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Josh House

Canadian Luthier Supply
http://www.canadianluthiersupply.com
https://www.facebook.com/canadianluthiersupply?ref=hl
House Guitars - Custom Built Acoustic Instruments.
http://www.houseguitars.com

I sometimes cut paper with it as well.

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http://www.CostaGuitars.com
PMoMC

With all due respect to several people who have answered, the simple and direct answer to your question is this: No, don't leave the edges sharp. Round them over to your own taste and satisfaction. How you achieve that is purely up to you, but I'll guaranty you that you can do it with sandpaper as fast as you can set up a router for the purpose. Whether plastic or wood bindings are used, you can do it very quickly and--more importantly--to your personal sense of feel and taste, with sandpaper in successive grits. Others might use routers for the purpose. If that's the way they like it, who am I to argue? It works for them. But I again assure you that you can keep doing it with sandpaper in the same amount of time or less time. You had it right all along. If you doubt me, time yourself both ways. Include the set-up time on your router--bit change, height adjustment, etc. etc. And while you're at it, evaluate the feel of the various round-over bits available. What if you decide that you prefer a round-over in a different radius? Do you want to include the time and cost of having a custom bit made? Plus the set up time? You should also weigh the risk factor of a router slip at 20 thousand rpm versus a sandpaper slip at hand speed, because that is a genuine concern. And even if you did rout the thing, would you go back with sandpaper to smooth it? I think you probably would. So why not just go to sandpaper in the first place? Consider all those factors. There is your answer from my perspective. I am sure someone will disagree. That's why this forum is such an interesting place to exchange ideas.
Patrick

I'm another sandpaper user. I like to use a small flexible sanding block like an eraser with maybe 150 to start and finish up with 220 just folded over a few times. Easy and fast. Do it however it works for you.

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Steve Smith
"Music is what feelings sound like"

In the interest of trying to be helpful, I have to post my disagreement with those that state that using sand paper is just as good and fast as using a router for rounding over binding edges. Having done it both ways I can tell you that when using sand paper I tend not to round them over as much and, if I tried, the edges would not be uniform and it would take me a long time. There is a significant difference for the better, for me at least, between the end result using a 1/8" round over bit in a router compared to doing it by hand. I would encourage people to do a comparison on some scrap wood.

Pat

_________________
There are three kinds of people:

Those that make things happen,
those that watch things happen,
and those that wondered what happened.

One time, I used the sharp corners of the binding one one guitar to round off the bindings on a second build. Never could figure out how to round the bindings on that other guitar. Still can't.

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http://www.CostaGuitars.com
PMoMC

That makes sense. I've thought about using a roundover bit but 1/8" was too big. I'll try your way. Thanks!

_________________
Alain Moisan
Former full time builder of Acoustics, Classicals and Flamencos.
(Now building just for fun!)