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Hi

Anything I'm missing with getting the kerfing to follow the shape of the back,
I can cut it into sections but doesn't look that good, any other ways?


Tia


Sent from my SM-A715F using Tapatalk

Most every guitar I build is a Manzer Wedge which makes the problem even worse. My way of dealing with it is to slice about 3/4 the way through the lining between each node and “fan” it to follow the rim profile either up or down. It remains a smooth looking transition because it’s still connected. Works for me.

Best, M

Am I imagining that I saw a kerfing product that was cut in two directions so it bent in two planes??

My take, Make side braces as wide as 2 sections of kerfing, run the braces full body depth, each side ends up being 4 or 5 individual pieces of kerfing, with 2 pieces of kerfing on the brace. Solves the problem of 2 dimension bending. The thought though is to reduce any stress riser that may be created by the kerfing.

B

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My memory is so good, sometimes I remember things that never happened.

I am using wacky wood linings which bend in two directions. On tight bends (waist area) it was showing some fracture lines which is a cosmetic issue so I started sanding the inner ply down closer to the center "spine". Ryan's A4 linings are cut in a way that allows them to bend in two directions if you don't mind the expense.
When I use more conventional linings I just break them where convenient and tolerate a little unevenness in height.

I've used the Ryan A5 linings and they work well. They're a bit pricey but compared to the overall cost of materials for a decent guitar it's not a big deal. I think it worked out to about $20 per guitar - worth the time savings to me.

Edit: Tapatalk made that photo huge. I'll see if I can fix it.

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Steve Smith
"Music is what feelings sound like"

Saw about halfway through a few kerfs in a few strategic locations. Cut the top or bottom depending on which way you need the lining to flex.

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Good judgement comes from experience. Experience comes from poor judgement.

I run mine under hot water and clamp to the rim allow to dry then glue them

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John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

I think the A4 linings have come down in price ($25 a set, now called A5?) but if you want to make your own:
https://www.youtube.com/watch?v=eq8O3uUilM8

Yeah, they're A5's. Last ones I got in Aug '18 were $25/set + $10 shipping. I bought several sets and if I recall, I got 3 guitars done out of 2 sets. That's not cheap but I'm not trying to make a living off of my guitars, I build for fun and the convenience is worth it. When someone wants to buy one they are priced accordingly. I've used laminated solid linings, reverse-kerf and standard-kerf; they will all do the job just fine.

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Steve Smith
"Music is what feelings sound like"

I've always installed kerfed liners in short sections. If you're careful you can get them to line up at the ends.

I use laminated liners for the arm and upper bout of harp guitars, making them on forms. The only way I've found to get those right is to make them wide, scribe them to the profile of the sides on the top edge, and trim them to uniform width from there. Sometimes the hard way is the only way.

I do kind of what John Hall does. Running them under some hot water and then letting them dry clamped in place will let the kerfing take just about any shape.

I have a small kettle that boils water very quickly that I use for hide glue. I get it to a boil and then bend the kerfing down into the bucket. Once it stops bubbling I pull it out and clamp it on the harder curved areas. Once it's dry it'll glue up much easier since it's already taken that shape.

I have always thought my guitars had a fairly pronounced for and aft arch and I have never had a problem with just kind of force fitting them. Might need to trim a bit off in places but I never found it to be a problem.

Same here.
If you do slightly mis-align, it's quickly cured with a chisel and sandpaper to make it much less noticeable.

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

I do what John does.

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It's not what you don't know that hurts you, it's what you do know that's wrong.

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The Ryan A5 linings come in short lengths to start with (7 1/4 inches). It kind of makes you wonder why you would need them .