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Dickey Bi-Flex Linings 2006

Well, during a recent vacation, riding a tour bus, I spy some dentil work on a vintage building. You know the kind, just looks like little blocks glued and spaced along a board, real nice look on an old building.

But, this was different... These dentils didn't go all the way through. They alternated with cuts from the top, then from the bottom, kinda neat, but different to the norm. Still had a similar effect.

Immediately, I called for a pen and paper and jotted the form down because I could see a solution to a guitar-related problem. Guitar dentils that don't flex, errrr, we call them kerfed linings.

Below, you see the modified reverse-kerf linings many of us use. I took a section and cut it to match the dentils I saw on the buildings. Cha-ching, the linings now easily flex in two directions, eliminating the problem of installing them on domed tops and backs.

Okay, this is a freebie for all my luthier friends. Just one thing, if you use it, simply refer to them as Dickey Bi-Flex Linings 2006. Try it on an old piece of lining laying around your shop. Yes, they will be slightly more delicate, but the force to install them will be minimal, because they are flexible.

This applies to triangular linings too, and I think that a double alternating cut to them as well will make them ultra-flexible.

Here is a pic of a reverse kerf lining with the Bi-Flex cuts added. I didn't try to be greatly accurate, just wanted to make sure it worked before sharing it. I got about 3/16 inch flexed curve in five inches without breaking.

Lance, how about putting this up in the jigs and fixtures section? Thanks, Bruce

Dickey Bi-Flex Linings 2006

Bruce,

That's brilliant!! Seems like it could be patented. Thanks for sharing.

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now known around here as Pat Foster
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http://www.patfosterguitars.com

Thanks Bruce, very clever !

Bruce,

A very interesting idea, and thanks for making it available!

I'm not sure, though, if I'm properly grasping how you're doing this. Maybe some "before and after" photos would help (with pictures of both sides of the linings). Thanks.

Looking at this idea objectively I have a few thoughts but more questions:

1) What problem does this solve? I am able to bend reverse kerfed lnings around the contour of the rims without breaking. I pre-bend them in my side bender. For me, I don't need more flexible liners in helping with the installation.

2) One purpose of the kerfed liners is to make the rims more rigid...presumably that's why the reversed liners were an improvement over the triangular liners. Going even further, Mario and Paul Woolson have made these even more rigid by adding a laminate to the outside. On the other hand, one could glue a laminated strip once the flexible liners were installed.

3) What difference will a more flexible liner have on the transfer of sound energy over that of a more rigid liner?

4) What effect will it have on the structural resistance to damage when dropped?

Bruce, with all due respect, I'm not trying to throw cold water on your idea...just trying to understand it and get the experts to chime in as to whether it has a true advantage. Perhaps Mario and Paul will comment.

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JJ
Napa, CA
http://www.DonohueGuitars.com

Okay. Start with a piece of standard or reverse kerf lining. We have no problem going around the curves because we've kerfed the lining, right?

Think of it this way, since the advent of the domed top and back, we have to bend in a third direction. So we have X, Y, and with the added half-cuts we can flex in Z direction, or the dome of the back, where we have the difficulty.

All you do is add a line down the center of the lining on the uncut side. Cutting in half way from the edge along the existing slots, gives you what you see in the upper photo. The lower photo reveals the back or glue side, no visual change, it's already cut there anyway.

Notice the inaccurate cuts done on my bandsaw from the frontside so I could see the line. Cut every other slot, halfway, flip the piece and cut every other slot from the other direction. IF you didn't stagger it, it would simply cut it in two, oops.

Try it, and you'll be amazed how flexible your linings will become. Simple change, big difference in the ease of lining installation.

Thanks JJ for your comments.

[QUOTE=Dickey]   Cutting in half way from the edge along the existing slots...[/QUOTE]
Sorry, Bruce. Does this mean to cut halfway between the existing kerfs, parallel to them?

Brillant

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Jim Watts
http://jameswattsguitars.com

Very clever.....

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"I want to know what kind of pickups Vince Gill uses in his Tele, because if I had those, as good of a player as I am, I'm sure I could make it sound like that.
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Cool idea Bruce!

[QUOTE=CarltonM] [QUOTE=Dickey]   Cutting in half way from the edge along the existing slots...[/QUOTE]
Sorry, Bruce. Does this mean to cut halfway between the existing kerfs, parallel to them? [/QUOTE]

Carlton,

No, you recut the existing kerfs through. The first one cut from the top and stop and the midpoint, the second one cut from the bottom and stop at the mid point then repeat. Like this.



The first picture in Bruce's post shows the end result from the back side (or front side since it's reversed kerfing)Scott Thompson38909.8285648148

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Scott Thompson
Port Townsend,WA

"In a perfect world we'd all sing in tune
But this is reality so give me some room"
-Billy Bragg

Scott, exactly, that was the view from the tour bus window. IT clicked in my pea brain that it would work to free up the kerfed linings in the third dimension. Good work there with all the little red arrows. How'd you do that? Grin.

I've got to agree with J.J., I think. Or I'm just not seeing a purpose here. Seems like removing the stiffness defeats the purpose of reverse kerfing. Why not just use regular kerfing? Help me.

Ron

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OLD MAN formerly (and formally) known as:

Ron Wisdom

Somewhere in the middle of Arkansas......

Ron, i have a feeling that this is the future of kerfed linings, the way it is explained by Scott, i think it will be plenty strong and more flexible thus easily worked with during installation!

Thanks, Scott. I get it now--alternating cuts!

Ron, The benefit here will be the ability to bend the lining up-and-down as well as forward-and-backward. Building with a high dome (or a low one, for that matter) requires making the lining conform to the irregular contour of the edge of the sides. Since regular linings can only be bent to fit the outline, and not the profile, of the sides, you could end up with short or uneven-looking linings. Looks like this might solve that problem. As for stiffness, well, as you know, everything in guitarmaking involves compromise of some sort. If you want to benefit from one change, you might have to find another way to compensate for it elsewhere. This new kerfing method may or may not cause a problem with stiffness. We'll just have to try it and see! Pretty cool idea, in any case!

Thanks, Carlton, at least I understand the purpose.

Ron

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OLD MAN formerly (and formally) known as:

Ron Wisdom

Somewhere in the middle of Arkansas......

I think this would be a good idea at the waist area in on the back as this is the area where the change in the Z direction occurs the most. So, maybe this would just have to be done in the waist area, not the entire lining.

Just my two bits.

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Very interesting Bruce,Thanks

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Anderson Guitars
Clearwater,Fl. 33755

[QUOTE=Serge Poirier] Ron, i have a feeling that this is the future of kerfed linings, the way it is explained by Scott, i think it will be plenty strong and more flexible thus easily worked with during installation![/QUOTE]

I disagree. I am in the stiffer is better camp. I do think it will help in installing them around the profile, but you want the rim as stiff as you can get it. I think weakening the linings is working against this goal.

No offense Bruce, the idea to make them easier to install is clever, I am just not sure it aids in the end product.

I am moving toward the capped linings to add stiffness.

Brock Poling38910.5553125

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Brock Poling
Columbus, Ohio
http://www.polingguitars.com

Thanks for your comments Brock.

This looks really cool, Bruce. I had a heck of a time getting reverse-kerfed linings installed on my still in-progress #1, with the tight curve around the waist, plus the arch of the back. I finally resorted to regular linings in 4" sections so I could more closely follow the arch.

I suspect the majority of the stiffness at where the plates meets the sides comes from the plate itself once it's glued together. In any case, it's still more stiff than tentellones!

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Jonathan Kendall, Siloam Springs AR

Isn't the whole idea behind the lining to increase glueing area? And, the only reason the lining was kerfed in the first place was to make it more bendable, right? Once the top and back are glued to the rim, isn't the box as stiff as its going to get?

Great idea Bruce! The ingenuity of the folks that frequent this forum always amazes me. Thanks for sharing.

JBreault38910.8280092593

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Joe Breault
Merrimack, NH
Perpetual novice

Thanks for your point Brock, i too believe that linings should make the joining stifer but as Rod said, i believe it could be done in tighter curves for ease of installation, especially in cutaways and as Joe mentionned, once the glue is applied to an increased area, you should get the desired stiffness? Right?

Maybe we oughta have someone test it somewhere first as a precaution and have the results shared here?