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Geoff B
Jun-30-2008, 11:28pm
Hey everyone, well, I'll be building an A-style with traditional holes (vs. my usual "bow-tie" holes as they've been called). I'm playing around with some lines, and while my focus is on keeping it more traditional, I thought it would be cool if folks posted their favorite hole shapes without having to discuss the benefit of F vs. oval, or placement, hemholtz resonance, main air mode, inertia etc. Lets just see some cool ideas!

Of course, if this has already been discussed, I clearly could not find the thread, so feel free to direct me and others to such a place!

Whoo hooo!

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Geoff B
Jun-30-2008, 11:31pm
Ok, I guess I'll start... here is my usual suspect:

Geoff B
Jun-30-2008, 11:36pm
here are some ideas I'm tossing around. #3 and 4 are pulling more from a violin background...

man dough nollij
Jun-30-2008, 11:43pm
http://www.elderly.com/vintage/items/images/90U/90U-4423_front-detail_sm_.jpg

(From Elderly.com)

Geoff B
Jun-30-2008, 11:50pm
here's one from D'Angelico

JEStanek
Jul-01-2008, 8:34am
If you're shooting for traditional and F holes on an A, why not go with the most coveted A with F holes (http://www.mandolinarchive.com/perl/show_mando.pl?51). Loar 74003.

http://www.mandolinarchive.com/images/74003_face.jpg

Jamie

bradeinhorn
Jul-01-2008, 8:39am
voight style

Hans
Jul-01-2008, 9:48am
For an F or A I'll stick to regular patterns, but for my own...

Steve Davis
Jul-01-2008, 9:59am
I like this one from kyswede:

sunburst
Jul-01-2008, 10:02am
Goeff, your drawing labeled "Loar" looks a lot more like the f-hole outline from the Siminoff book than it looks like a typical Loar f-hole. Compare it to photos of actual Loar mandolins, including the one in Jamie's photo to see the differences.

Here's my (brief) history with f-holes to give you an idea of the "philosophy" that I use for such design details.

I started out with the Siminoff (first book) f-hole because I used that book as a guide for building my first mandolin, then I made templates from the f-holes of a Loar and used variations on that shape for a while, always trying to get the shape to look better to me, then I saw an f-hole shape that I liked, so I stole it and started using that with only very slight variations so far.
For a traditional look, I think it might be better to use a typical Loar shape as a point of departure, but obviously, I don't recommend copying it exactly unless that is the look you want.
Don't overlook context when designing the f-hole, especially the relationship of the Fs to one another. Violin f-holes and mandolin f-holes define a space between them, and viewing the two together in their proper orientation is important to how they look, IMO. I haven't seen what I consider a successful adaptation of violin f-holes to mandolin because they don't fit the outline of a mandolin at all similarly to the way they fit the outline of a violin.

So, anyway, here is the f-hole I've settled on (for now at least) with the picture showing both holes for context. I think these look more feminine than the straighter holes in the squarer orientation typical of Loar mandolins.

earthsave
Jul-01-2008, 10:47am
For an F or A I'll stick to regular patterns, but for my own...
I like the look of that one.

Geoff B
Jul-01-2008, 3:47pm
John, you are correct about the Siminoff drawing... I scribbled Loar on there because Siminoff says it is from a Loar, it is the smallest of the ones with 4 sets on one page (don't have the book with me). I am no expert and I appreciate your input! I've gone ahead with something like #2, more curvy, etc.... pictures to come.

Nick Alberty
Jul-01-2008, 3:52pm
If they are called F-holes on an "F" style, then are they called A-holes on an "A" style?

Curious.....

earthsave
Jul-01-2008, 3:57pm
Only if your A has A-holes.

jimbob
Jul-01-2008, 4:08pm
The one labeled Loar looks most like the F-holes on my mandolins and is the one I am most used to seeing, so I guess I like it best.

Geoff B
Jul-01-2008, 8:04pm
If they are called F-holes on an "F" style, then are they called A-holes on an "A" style?

Curious.....
I was waiting for the A-hole double entendre. Well played!

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oldwave maker
Jul-02-2008, 8:01am
Started in the last century with the siminoff f holes, adapted old epiphone archtop guitar f holes after making a dozen Messiah copy fiddles(on right) , now gravitating to a Ziedler archtop guitar adaptation (on left). Vintage guitar magazine had an article about european archtop guitars a while back, lots of cool f hole designs there.

trevor
Jul-02-2008, 8:43am
Brentrup Stealth V3

trevor
Jul-02-2008, 8:45am
T' other side

Geoff B
Jul-02-2008, 11:09am
I really think the holes and the headstock are a place to make your mark, one where deviating from tradition won't change your sound. I'm all about making mandos that folks will love, so having a more traditional look is OK with me. I still couldn't bring myself to copy the Loar, so this is what I ended up with:

sunburst
Jul-02-2008, 11:41am
That top looks like compression grain spruce (or cedar?).
Have you used it before and with what results?

Dan Adams
Jul-02-2008, 2:27pm
The f-holes came out close to what John has been using and are also my preference. I really like the wave in the grain. That gives the top some added character. Dan

Geoff B
Jul-02-2008, 2:39pm
It is red spruce from Bruce Harvie. this is the second time using Red for me, I'm not aware that it is compression or what that means really. I asked Bruce for some wider grain stuff and he had this. Said it was milled in 1990. It taps really nicely, I'm expecting a good sound out of it, that's about as much as I know about it right now. It seems lighter than Sitka which is what I've used a bunch of, and a little stiffer than Engleman, in my experience at least. What is meant by compression grain?

sunburst
Jul-02-2008, 5:06pm
Compression grain is usually from a tree with a lean, or that grew on the side of a steep mountain. It is wood from the down-hill side of the tree where gravity and the weight of the tree cause the wood to grow with wider, harder grain lines. That is, the hard part of the grain is wider, not necessarily the distance between them on centers.

The reason I ask is: I've been hearing that some builders like compression grain red spruce and perhaps prefer it. I have quite a bit of it but haven't used any yet because I don't know exactly what to expect from it, so I'm interested in hearing from those who have used it as to whether or not they hear a difference over "normal" red spruce.

Spruce, if you're out there, where did that wood come from? Same place as mine?

earthsave
Jul-02-2008, 11:26pm
Compression grain is usually from a tree with a lean, or that grew on the side of a steep mountain. It is wood from the down-hill side of the tree where gravity and the weight of the tree cause the wood to grow with wider, harder grain lines. That is, the hard part of the grain is wider, not necessarily the distance between them on centers.

The reason I ask is: I've been hearing that some builders like compression grain red spruce and perhaps prefer it. I have quite a bit of it but haven't used any yet because I don't know exactly what to expect from it, so I'm interested in hearing from those who have used it as to whether or not they hear a difference over "normal" red spruce.

Spruce, if you're out there, where did that wood come from? Same place as mine?
Sure is purty.

Geoff B
Jul-15-2008, 10:07am
from another thread, I thought these beefcake f-holes were worth a look... or a chuckle...

A Korean Strad-o-lin...

Red Henry
Jul-16-2008, 12:38pm
There sure are a lot of cool f-holes on this thread (and a few others, as well). But it makes me want to note that (up to a point) the size or area of the f-holes may affect the mandolin's sound more than the exact shape does.

I have one quality mandolin with small f-holes, and it has a terrific bass and a lot of impact in the sound. I have another good mandolin with larger f-holes, and it really has a powerful treble, while retaining adequate bass.

Apparently, the f-holes function to some extent the same way as relief ports in a speaker enclosure, "tuning" the body cavity to optimize the instrument's acoustic output. Some builders I have spoken to were well aware of this, and others were not. But Lon Williamson, for one (a good builder in Florida) strings up his mandolins "in the white" with the f-holes still a little small, and carves them out gradually while playing, to bring the mandolin's treble/bass tonal balance to where he wants it. (I suppose this technique could also be used to customize a mandolin to fit a customer's particular tonal preference.)

Red

LateBloomer
Jul-16-2008, 6:50pm
Here's an f hole from my Unicorn - John Hamlett told me one time that it was rather distinctive...... I hadn't really thought about the various shapes of f holes before his comment.
Leigh Ann

Geoff B
Jul-17-2008, 12:34am
Yes Red, I've seen some of the threads here touch on the hole size. Basically it is based on Helmholtz' work with air cavity resonance. The formula takes several factors into account, but the 3 we have control over are the size of the hole, the volume of the cavity and the length of the neck (think bottle neck here). The length of the neck is influenced by the diameter of the hole, so taking that into account with the shape of the f-holes, the helmholtz equation serves (to me at least) as a rough guide. The frequency of the air resonance (main air resonance, in this case) is proportional to the square root of the area of the hole. So you double the frequency by quadrupling the area of the hole(s).

The other relationships for Volume and neck length are inverse square roots, meaning you halve the main air frequency by quadrupling the volume, or quadrupling the neck length. I've always thought there may be some awesome nuggets of truth in there, but in the end, it describes one resonance among many--you gotta take it for what it is.

An interesting anecdote I noticed one time is that the harmonics from an oval hole came out very predictably with less volume as you went up in harmonic number. But for f-holes, the first 3 to 5 harmonics were all major volume players and did not taper off the way they did with oval holes. On several strings it was in fact the 12th fret harmonic that rung the loudest (according to my computer, and my strobe tuner!). I always thought there was something to that as well, but I have yet to get a "eureka" moment from it.

Here is a familiair f-black-hole moment, the sciency post that incites a heated discussion about the role of science in luthery. I'd say my approach is that of a scientist who believes in magic, or an artist who believes in numbers.
Either way, keep those holes coming!

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laddy jota
Jul-17-2008, 4:34pm
Here are the holes I have been using lately.

LeonEvans
Jul-19-2008, 2:50pm
Steve Holst does these for both mandolin and arch top guitars. This is my C-5.

Leon

Alex of the North
Jul-19-2008, 3:33pm
Sounds like I'm too late to enthusiastically endorse designs three and four... I love the more modern (in typographic terms, which actually means early 19th century) ball ends...