Sound hole positioning.

[Bruce McC]

Hi Bob

Don't know of a formula as such but generally speaking the edge of the
soundhole aligns with the end of the fingerboard on a classical guitar.
Roy Courtnall "Making Master Guitars" has plans of a Hauser with the
centre of the soundhole being 152 cm from the body/neck join (12 th fret).

[Trevor Gore]

I'm not familiar with either of the Hauser plans, BUT check the scale lengths and the number of frets, especially between the body join and sound hole. 15mm is a lot of distance in these circumstances. Typically, the centre of the soundhole is somewhere a touch over 150mm down from the top of the upper bout for a split 19th fret and 650mm scale length. Any "formula" depends on how many frets you want from body join to edge of soundhole and the diameter of the soundhole, and that uniquely determines the soundhole centre position.

[Bruce McC]

The Hauser in Courtnall has a 650mm scale with a split 19th fret and sound hole radius of 42mm.

[charangohabsburg]

The Hauser in Courtnall has a 650mm scale with a split 19th fret and sound hole radius of 42mm.

Same thing with the 1937 Hauser that belonged to Segovia, but soundhole radius was measured as 43mm (according to the plans of Richard E. Bruné).

[simonm]

Might help if you mentioned which plans you have. I am only familiar with the Courtnall version mentioned a good few times already.

[charangohabsburg]

I have two plans of a Hauser guitar supposedly the same guitar

The plans I have been looking at are the LMI plan and one done by R E Brune of a 1937 Herman Hauser.

If your plans are from the same guitar the LMI plan of the 1937 Hauser is by Richard E. Bruné. Where did you get the other Bruné plan from?

[jeffhigh]

Must be hard to play, Lmi Lists the scale length as 6650mm!

[Nick]

Must be hard to play, Lmi Lists the scale length as 6650mm!

Not at all Jeff! just need a guy with completely out of the norm anatomy, a true knuckle dragger.

[kiwigeo]

Markus I have the 1937 plan of Sergovia's Herman Hauser and I picked up a plastic template Lmi's SPT 2 which is actually the 1943 Hauser. I have now figured out what the difference is between the two plans . It is your starting reference point. If you line the two plans up from the bottom then the sound hole is in a different position, but if you line the top of the top bout up you will find that the sound hole is in the same position on both plans it is just that the 1943 version is longer in the lower bout.Thanks for getting me to go back and check by your questions.
In th1943 model the bracing is heavier and there appears to be a couple of mm difference in the sound hole.
Thanks
Regards Bob

Bob,

Most of my classicals are built to Hauser specs. Im away at work so dont have access to the plans/templates I use. If you can wait till first week of September I'll be around then. Youre not too far away from me so it would be a good excuse for a workshop visit.

[charangohabsburg]

Markus I have the 1937 plan of Sergovia's Herman Hauser and I picked up a plastic template Lmi's SPT 2 which is actually the 1943 Hauser. I have now figured out what the difference is between the two plans . It is your starting reference point. If you line the two plans up from the bottom then the sound hole is in a different position, but if you line the top of the top bout up you will find that the sound hole is in the same position on both plans it is just that the 1943 version is longer in the lower bout.Thanks for getting me to go back and check by your questions.
In th1943 model the bracing is heavier and there appears to be a couple of mm difference in the sound hole.
Thanks
Regards Bob

Thank you Bob.
To me it would be a big surprise if any of the great luthiers would have made all his guitars to the same dimensions, and as Bruce mentioned there is no universal formula for where the soundhole has to be exactly on a classical guitar, although the 19th fret split somewhere by the hole is a generally accepted "standard", and the edge of the hole a bit above the waist height as well. This, together with the 12th fret position pretty much locks in soundhole position and size.