Official Luthiers Forum!
http://www.luthiersforum.com/forum/

A better way to cut bindings to length/nice miter?
http://www.luthiersforum.com/forum/viewtopic.php?f=10101&t=47731		 Page 1 of 2
Author:  rlrhett [ Wed May 04, 2016 12:07 am ]
Post subject:  A better way to cut bindings to length/nice miter?
I am betting there is a better way to do this than I'm doing this. I can never seem to get a really tight joint at the neck end. Even if the bindings on the top are hidden by the neck, the ones on the back should joint perfectly. With a cutaway I want a nice miter.

Using plastic binding (although same issue often with wood) if I start at a nice but joint in the back and slowly wind my way to the front I always have a little extra length. After all, I don't want to cut them too short and have a gap.

I usually glue one side perfectly to the body with a nice 45deg right at the corner. The other end I now have partially glued to the body with a floppy end about 6 inches long. I try to find some block of wood that is just the right height, mark the binding as best I can, peel it away from the guitar body a little, support it on the block of wood, and chop it with a sharp chisel. It is never a good cut. Chopping down on the binding across the narrow end is near impossible. The binding wants to move or flop over. Even if I do get a clean cut that is neither undercut nor flares out, I rarely get it EXACTLY the right length. A lot of futzing with the chisel leads to a barely acceptable end.

Is there a better way?
Author:  jsmith [ Wed May 04, 2016 12:26 am ]
Post subject:  Re: A better way to cut bindings to length/nice miter?
Make yourself a little 45 degree miter jig that you can use with your very sharp chisel. It takes the trial & error out of making miters. If I have time tomorrow, (and I remember) I'll take a photo of my jig. Of course, I only use the 45 degree jig for purfling joints. My binding joints are closer to an 8:1 taper. Then again, I use wood binding.
Author:  J De Rocher [ Wed May 04, 2016 12:50 am ]
Post subject:  Re: A better way to cut bindings to length/nice miter?
When you cut the binding, do you make a single cut to remove all of the extra binding length to try to end up with the final fit you want, or do you nibble away the extra binding length in a series of thin cuts that sneak up on the final cut?
Author:  rlrhett [ Wed May 04, 2016 1:17 am ]
Post subject:  Re: A better way to cut bindings to length/nice miter?
J De Rocher wrote:
When you cut the binding, do you make a single cut to remove all of the extra binding length to try to end up with the final fit you want, or do you nibble away the extra binding length in a series of thin cuts that sneak up on the final cut?


Both, but the problem is I don't have a good way of holding the binding firmly to take the thin cuts. Because I am cutting down with it standing on its thin edge it wants to roll. Also, it is always a little awkward trying to work with the 6" or so of loose end right next to the body. It takes a lot of force, even with a razor sharp chisel, to cut through 1/4" tall binding in one clean cut. It is hard to find a block exactly the right size to support it from below so I could bear down on it. All these things contribute to create bad cuts.

If I had a jig that would:

1) Hold the binding just off the body.
2) Support it so that it stands perfectly straight, won't try to roll over, and will support it from below so I can bear down on it with a chisel.
and,
3) Line the chisel exactly 45degrees to the travel of the binding.

I would be golden!!!!
Author:  J De Rocher [ Wed May 04, 2016 1:59 am ]
Post subject:  Re: A better way to cut bindings to length/nice miter?
The way you described supporting the binding on a block to make cuts is how I do it too. I cut the binding with it standing on its edge and haven't had a problem with it wanting to roll. What works for me is to first remove most of the excess binding length with my fret clippers leaving the binding about 2/16ths to 3/16ths long and then pare it down to fit with very thin cuts with a freshly sharpened chisel. By thin, I mean almost paper thin. Because it takes several cuts to pare the remaining length away, it lets me dial in the correct chisel angle for the final cut that fits. On the plastic tortoid and wood bindings I've used so far, thin cuts also result in cuts that are straight and don't cause the edges to flare out.

"It takes a lot of force, even with a razor sharp chisel, to cut through 1/4" tall binding in one clean cut." It shouldn't take a lot of force so it sounds to me like you may be trying to cut too far in from the end of the binding. Cutting off really thin slices takes only a small amount of pressure which means the binding is less inclined to roll and it also makes it easier to control the chisel.
Author:  Hesh [ Wed May 04, 2016 4:52 am ]
Post subject:  Re: A better way to cut bindings to length/nice miter?
I believe it was Terry Kennedy back in the day on the OLF who made a tiny mitre box just for this task. It looked like a good idea so I did it too and it worked great. I would use a Zona saw to cut to length on the guitar.
Author:  SteveSmith [ Wed May 04, 2016 5:24 am ]
Post subject:  Re: A better way to cut bindings to length/nice miter?
I also cut on the guitar. I mark with a 0.3mm pencil, mark the 45 and cut with an Xacto saw outside of the line. I final fit with the chisel. The mini miter box sounds like a good idea.

For plastic bindings I use acetone and weld the joints. You can make them seamless that way.
Author:  Woodie G [ Wed May 04, 2016 6:18 am ]
Post subject:  Re: A better way to cut bindings to length/nice miter?
Are you sure the miters are exactly 90 degrees? For a flush fit cutaway, the included angle may be greater than 90 degrees because the side has to run parallel to the fretboard. I kept getting an open miter on my test pieces when I marked and tried to cut them with a 45 degree miter box and a razor saw until I measured the angle and found it was a couple degrees greater than 90 degrees.

I also finally noticed that on the back, the miter is a compound angle for the piece of binding coming out of the cutaway - there is something like a 6 to 7 degree vertical angle on that piece.... I lay the cutaway side binding in the channel on the back and mark that angle to help me visualize when I rough cut to length and do final trimming for the compound miter.
Author:  Michael [ Wed May 04, 2016 6:50 am ]
Post subject:  Re: A better way to cut bindings to length/nice miter?
I just block sand the loose end until the fit is perfect. It never entered my tiny mind to do it any other way.

Michael
Author:  SteveSmith [ Wed May 04, 2016 7:29 am ]
Post subject:  Re: A better way to cut bindings to length/nice miter?
I think the message here is cut it to get close and then carefully trim for final fit. A variety of tools will work for this.
Author:  Ben-Had [ Wed May 04, 2016 7:50 am ]
Post subject:  Re: A better way to cut bindings to length/nice miter?
Here's a link to Terry Kennedy's jig, I use it too.

http://www.kennedyguitars.com/binding-cutting-aid.html
Author:  Terence Kennedy [ Wed May 04, 2016 8:16 am ]
Post subject:  Re: A better way to cut bindings to length/nice miter?
Ben-Had wrote:
Here's a link to Terry Kennedy's jig, I use it too.

http://www.kennedyguitars.com/binding-cutting-aid.html


Thanks, I still use it in pretty much the same form. I love it.
Author:  bcombs510 [ Wed May 04, 2016 9:49 am ]
Post subject:  Re: A better way to cut bindings to length/nice miter?
Terence Kennedy wrote:
Ben-Had wrote:
Here's a link to Terry Kennedy's jig, I use it too.

http://www.kennedyguitars.com/binding-cutting-aid.html


Thanks, I still use it in pretty much the same form. I love it.


I'd like to order one of these, please. Do you take Paypal? Seriously though, I will be using this from now on. The nibbling with the chisel on a wobbly pile of cutoff blocks will be no more! :mrgreen:
Author:  Terence Kennedy [ Wed May 04, 2016 10:36 am ]
Post subject:  Re: A better way to cut bindings to length/nice miter?
The jig gets you very close but it is best to error on the long side and fine tune the final fit with a sanding stick or file. Every now and then the fit will be perfect right off the jig.
Author:  mflazar [ Wed May 04, 2016 12:08 pm ]
Post subject:  Re: A better way to cut bindings to length/nice miter?
What a great thread and thanks to all of you. Unfortunately, I have no other tricks to add but I have a quote from my guitar crafting class with Greg Byers 14 years ago when I was expressing my fear of even trying to mitre my purfling joints. . He said "A mediocre mitre joint looks better than a perfect butt joint every time." I have to say I think he's right.
Author:  WaddyThomson [ Wed May 04, 2016 8:45 pm ]
Post subject:  Re: A better way to cut bindings to length/nice miter?
He's absolutely right! Mine are often close, but rarely perfect, but look OK.
Author:  rlrhett [ Wed May 04, 2016 8:47 pm ]
Post subject:  Re: A better way to cut bindings to length/nice miter?
OK, that Kennedy jig is smart. And yes, I guess I should be snipping with a end nipper or cutting with a razor saw to ALMOST, and then shaving with a sharp chisel. Sometimes, I guess, you just have to be careful and patient. Thank God most things on a guitar you can bang out carelessly and they end up just fine laughing6-hehe
Author:  DennisK [ Wed May 04, 2016 9:28 pm ]
Post subject:  Re: A better way to cut bindings to length/nice miter?
J De Rocher wrote:
What works for me is to first remove most of the excess binding length with my fret clippers leaving the binding about 2/16ths to 3/16ths long and then pare it down to fit with very thin cuts with a freshly sharpened chisel.

Yep, nippers work great on binding. I go more like 1/16" long so there's less to trim back. And I do my fitting before glue time, so I can chisel the easy direction, and sand if I can't get that to work. Trying to chisel down the long way just splits out the bottom most of the time. It's not so bad on softer woods like maple and koa, but usually I like using tougher stuff like rosewood so it won't get dinged up over time.

If you clamp with tape rather than rope or rubber bands, then you can glue one strip on, and then do final trimming on the other. Slightly more accurate than dry fitting everything at once.
Author:  J De Rocher [ Wed May 04, 2016 9:41 pm ]
Post subject:  Re: A better way to cut bindings to length/nice miter?
DennisK wrote:
If you clamp with tape rather than rope or rubber bands, then you can glue one strip on, and then do final trimming on the other. Slightly more accurate than dry fitting everything at once.


Thanks for pointing that out. That aspect of using rope or rubber bands seems like something worth considering. It hadn't occurred to me since I've only used tape.
Author:  Bob Shanklin [ Sat May 07, 2016 6:34 pm ]
Post subject:  Re: A better way to cut bindings to length/nice miter?
I generally use one piece bindings so the only joint is at the neck. The last one had 2 piece bindings and I got lucky with good butt joints at neck and tail.

Bob
Author:  wbergman [ Sat May 07, 2016 9:15 pm ]
Post subject:  Re: A better way to cut bindings to length/nice miter?
I have not read each post, so apologies if I am redundant. I have read where some people use a lap joint and it supposedly is invisible.
Author:  dofthesea [ Sun May 08, 2016 12:11 am ]
Post subject:  Re: A better way to cut bindings to length/nice miter?
Something that might help is to not have your perfling and binding at the same joint. I like have a few inches off separation.
Author:  rlrhett [ Sun May 08, 2016 3:40 pm ]
Post subject:  Re: A better way to cut bindings to length/nice miter?
Quick question for those who finalize the cut with "sanding". How are you doing this? What kind of sanding block are you using to ensure a flat sand? Again, how do you hold/support the binding and/or block? I tried that and it seemed pretty hap-hazard what the sanding paper was doing.
Author:  DennisK [ Sun May 08, 2016 4:02 pm ]
Post subject:  Re: A better way to cut bindings to length/nice miter?
rlrhett wrote:
Quick question for those who finalize the cut with "sanding". How are you doing this? What kind of sanding block are you using to ensure a flat sand? Again, how do you hold/support the binding and/or block? I tried that and it seemed pretty hap-hazard what the sanding paper was doing.

I don't have any tricks. Just hold it near the end, rub it on the sandpaper, look at it, and if the angle is wrong then repeat with it angled slightly differently or just focusing more pressure on the high point.

wbergman wrote:
I have not read each post, so apologies if I am redundant. I have read where some people use a lap joint and it supposedly is invisible.

If you do that, make sure the runout is matched between the two pieces... especially with highly reflective woods like koa, mahogany, purpleheart, movingui. Frustrating when you make a perfect joint, only to realize that it sticks out like a sore thumb anyway after you sand it smooth and apply finish [headinwall]
Attachment:
BindingScarf.jpg


I've had pretty good luck with butt joints if they're well fitted and I stretch a strip of tape across to apply pressure. Same principle as the tape method of plate joining. Works best of you tilt one of the pieces and stretch the tape across the gap to get more tension on it when the joint is closed. Hesh posted a good photo here that's worth a thousand words of trying to explain what "stretching across the gap" means :)
Author:  wbergman [ Sun May 08, 2016 6:21 pm ]
Post subject:  Re: A better way to cut bindings to length/nice miter?
Wouldn't the run out reflective problem be the same with a butt joint?
Page 1 of 2 All times are UTC - 5 hours
Powered by phpBB® Forum Software © phpBB Group
http://www.phpbb.com/