Sinking the recurve

[Rick Lindstrom]

I searched the archive for "recurve", and came up with more hits than I wanted to sort through.

Since my question is simple, I'll just ask: for the top plate, on average, how far from the edge of the plate is the deepest part of the recurve located, and what is the final thickness of the plate at that point (ie- how deep is the recurve).

I know that the answer to the thickness part is "it depends" on things like stiffness and the builder's intent with regard to sound. That's why I said "on average. I'm doing a first build and need a ballpark estimate since I probably won't be able to flex the top and intuit how deep the recurve should be.

Thanks-

Rick

[Geoff B]

Seems to me the lowest part falls around 3/4" from the side. Sometimes as much as an inch and sometimes less (like 5/8). Not sure how big a difference it makes, but mine usually end up 3/4-7/8 inside the edge. doing a search on carving specs or plans might yield some more information.

[Michael Lewis]

Recurve can take just about any configuration. As a couple examples, John Zeidler used what I would call a micro recurve that took place in the last 1/2 inch or so from the binding, and Bob Givens used a very wide recurve of maybe 2 inches with a small dome in the center of the top. These are the most extreme examples that readily come to mind.

What is your reason behind your recurve? If it is just for visual appeal then just do whatever it is that makes it look good to you. If it is for tone control you will have to get deeper into the structural design in order to come up with a good concept, then you will have to make a bunch of instruments to develop and prove your ideas. it ain't black and white.

From my perspective the recurve acts as a flexible zone around the edge of the plates. Just how flexible depends on how deep you make it, how close to the edge it is, how much of an "S" curve it contains in cross section, how much the surface dips "negative" from the binding, how the internal arching incorporates into the design, the thickness of the minimal area, stiffness of the wood, etc. Practice makes perfect, sort of.

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[mandolooter]

well put Mr Lewis...its kinda like rocket science...lol! http://www.mandolincafe.net/iB_html/non-cgi/emoticons/tounge.gif

[Spruce]

If you want to see something really interesting sometime, check out the recurve on a D'Angelico mandolin sometime.....

It's very deep, and maxes out about as far from the rim as you can get...

And it works....


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[sunburst]

I've seen and heard mandolins with no recurve at all, with narrow recurve areas, wide recurve areas, deep ones, shallow ones...they all sound like mandolins.

[bkhooper]

I saw a older model varnished Daley this past weekend at the farmfest festival that had almost no recurve at all...Sounded very good...

[Michael Lewis]

The recurve in the Loars varies considerably, showing they changed over the years. Are they better one way, or the other?

[Links]

Those were all great answers, but none of them answer his question. Can't someone come up with a generic answer like - "most modern Gibsons are approximately 1" from the binding, about 1/4" below the plane of the sides, and approximately 3/16" thick at the re-curve". I get the impression that he understands (or knows they are there) the variables in the wood stiffness, desired sound, etc. but just wants some general guidelines. Tough to generalize I know - but>>>>>>>>>>>>

These answers remind me of the answer I get when I ask my golfing partner how much a putt breaks. "Depends on how hard you hit it." Duh!

[sunburst]

Those were all great answers, but none of them answer his question. #Can't someone come up with a generic answer like #- #"most modern Gibsons are approximately 1" from the binding, about 1/4" below the plane of the sides, and approximately 3/16" thick at the re-curve".
Nope...
well, I guess I could say "go in 3/4" from the edge and cut a groove 2mm deep around the edge but stop about 3" from the neck area", but I could also say "go in 1" and cut a groove 1mm deep all the way around the plate". One is no more "right" than the other however, and there are many other answers just as valid.

[Rick Lindstrom]

Thanks John and Paul and everyone else who responded. I did indeed decide that there is no hard and fast rule here and that I can just do whatever looks good to me.

I like the "progressive recurve" on the old Gibson that someone linked to, and that approach will fit nicely into what I've already done. When I find the center of that recurve, I'll draw a line down it and then sink it about 2mm or maybe a little less. That'll will give me a bottom limit for the carving, and leave me just a little extra there in case I want to refine it a bit.

Thanks for the input!

Rick

[Jerry Stapleton]

I asked the same questions when I began this madness,and I got the same answers that you have gotten. Now after building a few and having a small bit of experience under my belt(Still just scratching the surface) I have found that while carving a plate, I chisel,scrape,sand, flex, tap,feel, listen and pray. work and work at it(Which I find to be so much fun!)then all of a sudden one day I stop doing all these things and realize that its ready. so, not to make this story any longer, I can tell you that you will probably know when its ready. http://www.mandolincafe.net/iB_html/non-cgi/emoticons/laugh.gif