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I made some mahogany kerf linings for my test project tonight. I pretty much followed the recomend practices of cutting them. I probably left about a 1/32 of wood on the back. (meaning I cut the kerf almost all the way thru, leaving a 32nd of wood on the back side). For the most part, my spacing was about 1/8" between kerfs. I had the hardest time trying to bend them around the portions of the upper bout, the waist and almost all of the cutaway area. Even breaking them into small sections I had issues.

I am not sure what the grain direction was in these pieces. They were cut offs from an old board that were the right size. I even tried wetting them a little which seemed to help, but no luck in the tight areas. Could the grain have been running the wrong direction? Is other wood better for this purpose when tight bends are needed? Anyone tried Aspen for this?

Joe

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Joe

Sounds like too much runout to me. If your kerfs are 1/8" wide with a 1/32" web, then you have about a 4:1 ratio. So you should use wood with runout less than 1/4" per inch of length. Otherwise the linings will break at the kerfs. Did you split a piece to see how the grain is running?

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Horton, MI

1/32" web is too much. When I make mine, I group them into "stiff" (about .023" web) and "flimsy" (.013 to .015" range) & still break some. You can individually adjust a piece by lightly running an exacto blade through each kerf.
p.s....I assume you meant 1/8" c/c kerfs rather than a 1/8" wide kerf

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Dave
Milton, ON

Ha! Yes, the kerfs are cut about 1/8" appart from each other. Sorry for the crappy use of terminology.

No, I did not split it to see the grain. I had 4 pieces of mahogany (I think...it was hard to tell if it was Mahogany or walunt...but I think it was mahogany). They were essentially 5/8" square sticks. I set up the band saw on a 45* and cut them down the middle. So each piece made two lengths. I then made a few nice cuts to make it look pretty and then cut the kerfs. I had tried the same think with a very short piece of basswood, and I could bend it into a 2" circle. THe mahogany with the same shape and kerf would hardly get around the upper bout let alone the tight waist or cutaway.

More things I guess I need to learn. I have very good woodworking skills, but very little expierence with building guitars. I can repair the crappy out of one that is already built...lol, but most of this contruction stuff is new to me.

Thanks again guys,

Joe

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Joe

1/32" too big. 1/8" too small. Try looking at a piece of manufactured lining.

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Howard Klepper
http://www.klepperguitars.com

When all else fails, clean the shop.

Thanks Howard. The 1/8" was due to the cutaway and waist radius being very small. Anything larger seemed to bind between the kerf. I will try again with a deeper cut reducing the web to maybe 1/64".

One of the reason I was wondering about grain direction is because I often see "manufactured" linings with 1/4" wide spacing and it seems to bend ok in most places. The trial pieces I made did not bend very well with 1/4" spacing. Part of this may be the wood and grain orientation.

One other thing to mention, the bandsaw blades I have been able to get for my saw seem to have very little set to them. The kerf is very thin and at times makes cutting even the most gentle curves a bit tough. I am not sure why the 59.5" blades I have been buying has such little set in them. Even the 3 TPI blade I bought for resawing has almost no set. I wonder if the very thin kerf is also part of my problem with the linings?

Thanks,
Joe

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Joe

Joe, I enlarge the kerfs for the tight bend areas. It's needed with reverse kerfed linings.

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Howard Klepper
http://www.klepperguitars.com

When all else fails, clean the shop.

Joe,

I've got a piece of reverse kerfed lining you can use for a pattern. I think they're way better than the standard. Like Howard said, enlarge the kerfs on the tight bends. I've also had luck with throwing the linings on the bender. On Saturday I'll be at the shop to bend the bindings for my OM, after that the heat blanket will be sitting idle for a while if you want to borrow it.

Steve

I used quarter sawn Narra for reversed kerf linings on my latest, kerfs about 1/4" apart (maybe 3/16" is closer) and 1/64" or so worked out ok, but I had to pre-bend them in the fox bender with a light spritz of water. Made the job a lot easier by bending them first.

Hi Steve. I play out in Elburn saturday afternoon if your wanting to listen to some music...I need to come by your place anyway to give you back those necks and stuff. I'll bring by the carved top/back and neck. I am still working on getting the body parts right.


Everyone, I cut some more test linings this time using quarter sawn pine. With a touch of water, they bent around the body much better than the mahogany stuff. I am pretty sure the grain direction must play a little roll in how stiff or brittle they can be. I also tried some poplar and some basswood. The both worked better than the mahogany I tried using early. I am wondering what the grain pattern was on the mahogany pieces I cut. It was too hard to tell when I was working with them the other night.

Ciao
Joe

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Joe