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This weekend I made up some kerfed linings Cumpiano style. when test fitting my first, it split at the waist. In fact I split three at the waist.



Is it ok to wet this area of the lining and then glue it? I not sure if this will wreak havoc on the area as it dries. Also, is it ok to use the cracked lining?
thanks.

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Chris Oliver
Infinity Luthiers
...in the shop.

live every minute...

Chris, it's okay.

Looking at your spacing, I'd say this is shopmade not factory lining? Just guessing.

You can make the linings much more flexible by making smaller width spaces on the lining.

Or, you can make it more flexible, by double cutting the linings.

By double cutting, I mean cutting into the blocks from the back side, hence giving room for the wood to conform to the curve of the guitar side.

I don't know of anyone doing that, except the recent Ryan linings which were posted by Cornerstone recently.

Like I said, it is okay to just glue and go. But learning something here is probably more important. How to, easily, make it work better in the future, eh?

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http://www.dickeyguitars.com

Looks like the depth of your cut is inconsistent and appears to be a bit shallow.

The cracked lining will work OK, unless you're using reverse kerf to get a stiff rim.

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

You can glue them either way, but you will need to take the cuts a lot deeper at least in 3 bent areas, or try double cuts as Bruce suggested. I made a test piece after reading that recent thread, and it does create a very very flexible line indeed. 

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Build log

Once you get the cuts a bit deeper, another trick is to put a piece of tape (good masking tape or similar) along the side with the cuts before you bend it at the waist. This helps to control the bend and reduces breakage.

This is a tip I got from Jeremy Clark, and it does work well if you are using slotted linings (aka kerfing).

Cheers
John

Thanks for the tips everyone. I'll get the hang of all this in a year or two.

I made the lining according to the Cumpiano book with just a 1/64" thickness of what he called the 'web' and 1/4" or less spacing between kerfs.

Hesh: The do have a chamfer on them. They just weren't visible in the photo above since I was taking the pic from the top. I do like your joining of the two pieces. That is good to know. Thanks.



chris

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Chris Oliver
Infinity Luthiers
...in the shop.

live every minute...

I glue mine up like Hesh does, with the kerfed part toward the side of the guitar. The only exception to this is when I use the "triangle" kind of kerfed linings (which I dont use any more)... for those I expose the kerf's to the inside of the guitar. By gluing it up as a "reverse" lining, it gives a more "clean" look to the inside of the guitar and I also believe that it makes the sides of the guitar a litle stronger. (this may be another fairy tale, but it is what I believe to be true)

You will find that by placing the kerf toward the inside, you have less of a chance for it to break. I also try to just bend it one block at a time when I am gluing it up. I use clothes pins to hold it while the glue dries. I havent tried soaking the ribbon in hot water... this may be a new and useful trick

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Reguards,

Ken H

I'm a first time builder, so I have little experience, but I bent my kerfed linings with my "light bulb" side bender. I just wiped some water on the plain side of the lining and bent with no problems. The gluing up was very easy, since the linings didn't have to be "coaxed" to fit the shape of the sides.

Ray

[QUOTE=Ray Pepalis]I'm a first time builder, so I have little experience, but I bent my kerfed linings with my "light bulb" side bender. I just wiped some water on the plain side of the lining and bent with no problems. The gluing up was very easy, since the linings didn't have to be "coaxed" to fit the shape of the sides.



Ray[/QUOTE]

Doh! .... I have a perfectly good pipe side bender I built a few weeks ago. I guess I could coax it a little in the waist area first.
thanks to all for the tips.
chris

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Chris Oliver
Infinity Luthiers
...in the shop.

live every minute...

I throw mine on my side bender before installing them.  That pre-bends them and keeps them from breaking at the waists.

This what they look like out of the bender just before glue-up.

I just wet the non kerfed surface with a wet sponge and warm them up with a heat gun, clamp them to the sides until they're dry. Then glue.