Amount Of String Stretch For Tuner Design...

[cbowen]

I'm looking at making my own linear tuners for a tap guitar project (12 strings). What I'm wondering is how much stretch I need to accomodate. I want to make something similar to the Steinberg linear tuners, but I have no idea what range of stretch they accomodate. I know even they have problems sometimes with high strings. Would 0.75" be enough or do I need an inch or more?

[Robert Irizarry]

First question - Are there no tuners that would fit what you are trying to accomplish or is part of the goal making the tuners? Maybe some kind of diagram could help get some ideas from the fine folks here. Also, I own a Hohner licensed version of the Steinberger and I've never had issues with tuning. Second question -Are there any measurements I can take that on the bridge that might help?

[cbowen]

First question - Are there no tuners that would fit what you are trying to accomplish or is part of the goal making the tuners? Maybe some kind of diagram could help get some ideas from the fine folks here. Also, I own a Hohner licensed version of the Steinberger and I've never had issues with tuning. Second question -Are there any measurements I can take that on the bridge that might help?

Here's the plan: 12 strings, 0.300" string spacing. Two groups, with 0.380" between the two groups. It's a combination of wanting to go headless and yes, I really do want to make the tuners. Probably cost me 10x as much as buying them, but we're not in this for the efficiency, right? I've alread built a custom bridge, but I may redo it since I was originally going to use conventional tuners and a headstock. I just could not get the slim look I wanted with that great big 12 string headstock up there.

The plan is 0.290" diameter knurled knobs and 6-40 threaded rod. 40tpi should give me plenty of precision. My main concern is how long the threads need to be. Do I need 0.5" of adjustment range or 1.0"?

Other problem I've not figured out a good solution for is how to anchor the string. Can you clamp onto a 0.007" string with an aluminum clamp without weakening it at that point?

Thanks, and having fun with the lathe,

Charles

[Robert Irizarry]

Here's the plan: 12 strings, 0.300" string spacing. Two groups, with 0.380" between the two groups. It's a combination of wanting to go headless and yes, I really do want to make the tuners. Probably cost me 10x as much as buying them, but we're not in this for the efficiency, right? I've alread built a custom bridge, but I may redo it since I was originally going to use conventional tuners and a headstock. I just could not get the slim look I wanted with that great big 12 string headstock up there.

The plan is 0.290" diameter knurled knobs and 6-40 threaded rod. 40tpi should give me plenty of precision. My main concern is how long the threads need to be. Do I need 0.5" of adjustment range or 1.0"?

Other problem I've not figured out a good solution for is how to anchor the string. Can you clamp onto a 0.007" string with an aluminum clamp without weakening it at that point?

Thanks, and having fun with the lathe,

Charles

Interesting project. I've been thinking about headless designs for a while now and one solution I've seen is the use of a conventional locking nut to anchor the strings. I've seen several examples of this as an alternative to using the stock headpiece (expensive) and double ball end strings (for some, hard to obtain). I think that if you model you're clamp after something like that, you should be fine. I would go with something like the Kahler style locking clamp that fits after the nut. Because its after the nut, you don't have to worry about its radius. Its just there to retain the strings.

Here are a couple of examples using locking clamps/nuts:

Chris Shaffer Headless @ Kronosonic.com

Cotta Guitars Klein Replica

As far as the adjustment range, if its any help, I'd be glad to get you an estimate of the adjustment range of the tuners on my Hohner headless as well as any other dimensions you might think helpful. Its currently strung with .010-.046 strings if thats any help. And again, I've never had problems tuning it. Let me know and I'll get these measurements for you this weekend.

[cbowen]

As far as the adjustment range, if its any help, I'd be glad to get you an estimate of the adjustment range of the tuners on my Hohner headless as well as any other dimensions you might think helpful. Its currently strung with .010-.046 strings if thats any help. And again, I've never had problems tuning it. Let me know and I'll get these measurements for you this weekend.

That would be great. I'm sure I can work in the same range.

[Robert Irizarry]

As far as the adjustment range, if its any help, I'd be glad to get you an estimate of the adjustment range of the tuners on my Hohner headless as well as any other dimensions you might think helpful. Its currently strung with .010-.046 strings if thats any help. And again, I've never had problems tuning it. Let me know and I'll get these measurements for you this weekend.

That would be great. I'm sure I can work in the same range.

I'll get the information for you and post it by tomorrow. Stay tuned...

[Robert Irizarry]

As far as the adjustment range, if its any help, I'd be glad to get you an estimate of the adjustment range of the tuners on my Hohner headless as well as any other dimensions you might think helpful. Its currently strung with .010-.046 strings if thats any help. And again, I've never had problems tuning it. Let me know and I'll get these measurements for you this weekend.

That would be great. I'm sure I can work in the same range.

I'll get the information for you and post it by tomorrow. Stay tuned...

Here's what I came up with off the R-trem type bridge. The threads on the tuners is a hair over 1" - about 1 and 1/16". That 1/16" is taken up by two tiny washers that are under the tuner knob as it comes up against the bridge. I couldn't get at the jaw that holds the string in place (without unstringing the guitar at the moment but it appears to be approximately 24/32" long. This is the piece the threaded knob connects to. Inside the bridge, there is a spring through which the tuner rod runs. Another piece that is probably important is the neck side of the equation. This is a little harder to measure but the strings anchor into the headpiece approximately 24/32" above the bottom edge of the zero fret.

Hope this helps a bit. Let me know.