First Build questions

[Jeremy A]

I am building my first mandolin - based on Gibson A3 plans, with oval hole.
First question - nowhere can I find information on the neck angle. Can someone help please?

Second question - 12th fret or 15th fret, which is best? Also is it better to use a seperate fingerboard extension support or carve the front so that the extension rest on the front?

Many thanks

[buckhorn]

The angle at the heel changes how high the bridge will be.. I try to keep it around 4-5 degrees. the ach high of the top will also, but the heel angle makes the biggest difference...

[Jim Hilburn]

This might help.

[Sam Schillace]

What plan set is that? I’m also starting a build and looking for good A-style plans.

[PEIMike]

What plan set is that? I’m also starting a build and looking for good A-style plans.

I just ordered a book, comes with plans. Im not sure if theres any A style plans, but have to start someplace.
this is the book, "The Mandolin Project: A Workshop Guide to Building Mandolins", and the author is Graham McDonald.

[Jim Hilburn]

Scott Artes
Not sure where to find them. But a very accurate oval plan.

[HoGo]

Get a good plan of what you are going to build and plan ahead every part. The angle will be result of how deep the neck will be installed into body and how high arch you have. You NEED to install it at an angle that will give you just the right bridge height. I never measure the angle, just the projection of the neck. I've seen many beginners mandolins with neck angle so shallow that there was very little space for proper bridge or few with angle so high that custom bridge had to be made...

[Bill McCall]

HoGo’s plans from Elderly are a great place to start. Then make your own full-size layout.

[HoGo]

HoGo’s plans from Elderly are a great place to start. Then make your own full-size layout.

He wanted to build A style. There are the Scott Antes plans and also James Condino (at GAL) plans for archtop A oval.

[Jeremy A]

He wanted to build A style. There are the Scott Antes plans and also James Condino (at GAL) plans for archtop A oval.

I am using -as a guide - plans from Georgia Luthier Supplies. These are supposed to be modelled on a Gibso A3. I also had a plan from John Anthony Guitars, but that was not suitable.

The GLS plans show a 15th fret joint. They also show a riser for the fretboard extension. Most - if not all - of the photos of A3's show a 12th fret joint and a ramp carved into the front for the fingerboard extension.

I have read several other threds on this forum to which some of you have contributed. I am becoming confusesd as to the best way forward! What are the ramifications of using either joint? Does the choice of joint affect the graduations of the front? Which produces the better sound - ramp of riser?

Jim, I notice that the extract you posted is a 12th fret joint and a ramp. Is that your preferred design?

Sorry for all the questions - I have to make some decisions before I go any further.

[HoGo]

I am using -as a guide - plans from Georgia Luthier Supplies. These are supposed to be modelled on a Gibso A3. I also had a plan from John Anthony Guitars, but that was not suitable.

The GLS plans show a 15th fret joint. They also show a riser for the fretboard extension. Most - if not all - of the photos of A3's show a 12th fret joint and a ramp carved into the front for the fingerboard extension.

I have read several other threds on this forum to which some of you have contributed. I am becoming confusesd as to the best way forward! What are the ramifications of using either joint? Does the choice of joint affect the graduations of the front? Which produces the better sound - ramp of riser?

Jim, I notice that the extract you posted is a 12th fret joint and a ramp. Is that your preferred design?

Sorry for all the questions - I have to make some decisions before I go any further.

Since I build F-5 only I cannot talk about building preferences. I would likely consider short neck and ramp over extension suport and long neck for oval. The long neck IMO puts bridge too close to hole and makes the top more prone to sagging unless you do some sort of cross bracing.
Regarding drawings, basically all you really need is body shape and general arch shape and length of neck/ fingerboard. Everything else can be adjusted as you go. If you look at the side view, the typical oval has ramp that is a bit lower than 1/2" (rim to fretboard) at the crosspiece (12th fret for oval), for typical F-5 it is 1/2" at the crosspiece (15th fret). If you use the same angle on both and same arch height, the bridge will be almost same, perhaps tad lower for oval (the ramp is lower but the distance to bridge from crosspiece is longer).
When you carve oval with ramp you need to leave there extra wood for neck fitting at correct angle for good bridge height.

[Jim Hilburn]

The print I have is of teens era Gibson oval which I assumed is what you want to build. Doesn't matter which number ( A-1 , A-3 etc.) they were all built the same way.
The F-5 is the instrument where so many changes took place including the 15th joint and elevated board.
I only built one oval and it was a hybrid with 15th and elevated board. That required some engineering and plan drawing and I don't know if anything like it exists for sale.
So you have to decide what you want to build. Ovals have their unique sound, but the F5 sound has become far more popular. The oval design in my opinion has a lot of design issues that were addressed with the F-5.
If you want to do an oval see if you can get your hands on one to see how it was made. There are thousands of them around.

[Jim Hilburn]

As to Adrian's observation, I moved the oval forward and used an X brace and did a lot of praying.

[Jeremy A]

Did it survive, Jim?

[Jim Hilburn]

Oh,Yeah. Gets played all the time.

[amowry]

I usually build my oval-hole mandos with the neck joined at the 14th fret, an elevated fretboard, and an X brace. The neck angle is the same as with F5s. The combined effect of these things is (naturally) that the sound is somewhere between that of an F5 and an A4 (A3, etc.). To me, the upper and of the range sounds more like an A5, and the lower end sounds more like an A4 (it has that "round" sound, but maybe not quite so "tubby".

One thing you have to be careful with is that the main air resonance will want to be close to a G with these "hybrid" oval holes, which will make the G strings really boomy. To prevent this, I carve the top and especially the back a little thicker than I would with an F5, and stiffening those up seems to help bring the air resonance up to around a G#, which works well. I believe I got that bit of wisdom from Peter Coombe a number of years ago. You could probably tweak the soundhole size a little to have a similar effect.

[peter.coombe]

I use a neck angle of 4.5deg and aim for a bridge height of 19-20mm. Elevating the fretboard or moving the neck forward will change the sound. It is a matter of what sound you prefer, a true oval hole sound or something in between. I prefer the true oval hole sound.

For a comprehensive description on how I make them see -
http://petercoombe.com/construction.htm

[Dale Ludewig]

I do my instruments like Andrew described. Join at the 14th with an elevated fingerboard. I also pull the oval hole forward so that the bridge isn't close to the sound hole. And I Xbrace also. And there's even more- I agree about the sound. It can border on tubby on the bottom. The one I've kept here is redwood top.

[Larry Nixon]

Scott Artes
Not sure where to find them. But a very accurate oval plan.

Stewmac has A-3 plans. Siminoff has A plans. Neither as good as Georgia Luthier plans. Hobo are pricey but probably worth it.

[j. condino]

Condino / Guild of American Luthiers' 1926 snakehead plans:

[Jim Hilburn]

One aspect of the oval mandolins you can clearly see in Jame's print is the flat top behind the oval as opposed to the true dome on an F5. The only way for the bridge to work with the fingerboard attached to the top.

[j. condino]

Pick something simple that you can build to completion rather than an over complicated, overly ambitious project that never gets finished and is abandoned to your closet of life's unfulfilled anxieties.

No binding, no inlays, no bound fingerboard, moderate materials; basic.

The Smithsonian can wait for your number two build for their permanent collection.....

[Jeremy A]

Thanks everyone for all your thoughts, opinions and advice. There has been much to ponder!
I have decided to use the plans from Georgia Luthier Supplies for the body shape & size (13"), but to fit the neck joint at 12th fret with the ramp for the fingerboard extension carved from the top - I prefer the look of that method!
I shall have to move the oval hole, the bridge and the X-brace back about 3/4". Presumably I shall also have to move the centre of the graduation back also, so that the bridge feet are on the thickest part of the top - further study to be made on that issue.
I have been looking at graduations on other threads.

I have a further question about necks and grain orientation. I am hoping to use maple - to match the sides. However my bolck of maple was originally for a cello where the grain, traditionally, runs parallel to the plane of the fingerboard. I am told by others that the grain should be at right angles to the f/b. I am possibly considering a three piece neck - maple/mahogany/maple, or even a solid mahogany one. I shall use a carbon truss rod. Your thoughts will be welcome.

[peter.coombe]

If you are using carbon fibre in the neck don't worry about it. All violin necks have the grain oriented that way, and I have used violin neck wood in some of my mandolins many times with no problems.

[Marty Jacobson]

One thing I think is very important about building an oval-hole mandolin is the graduation pattern. I've posted this a bunch of times, sorry if you're tired of seeing it.

Most mandolins have their graduations approximately like this:

Red is thickest, green is thinnest.


But an oval-hole mandolin should be more like this: