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Ok so I’m penciling in the brace positions on the back of the soundboard for my L-00. I’m using the Grellier plan for this one.

A link to the plan on his site:
http://www.grellier.fr/plans/Gibson_L-0 ... -00_en.pdf
On the plans there are dimensions for the center point of the sounhole and for the size of the braces, but I am having a hard time accurately locating the braces.

I have the X brace marked, but am not sure exactly where to put the bridge plate. I know it needs to relate to the saddle position. Scale length on these plans is 24.75” (630mm) for a 14 fret neck. I’m thinking the center of the saddle should end up at half the scale minus the distance between the 12th and 14th fret (I haven’t done the math yet and it is late). Typically how do you orient the bridge place relevant to the saddle position? Some of the bracing I'm sure can be approximated, but this one I'm thinking needs to be located fairly accurately.

I have made the body a bit smaller that the plan indicates, but had intended to orient everything from the neck joint and follow the dimensions as indicated in the plan. I'll keep a record of where the braces end up for reference in future builds.

Thanks for the advice,

John

John : Think you are headed down the correct path.I like to lay out the whole pattern of the bracing plus the bridge shape with saddle location. Just a few points I follow. Make sure to include set back for intonation,check to make sure bridge gets proper support over X brace,allow at least 1/8" in front and in back of saddle on bridge plate size.Finally make sure to ACCURATELY position your top during glue or all may be for naught.This may seem redundant but the neck must be constructed so that the 14 fret is ACCURATELY placed on guitar. This seems to work for me.
Tom

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A person who has never made a mistake has never made anything!!!

I want to use this plan too.

In the CAD plan the top of the bridge plate is 5.09372 from the center of the sound hole and the bridge plate is 1"" wide. It is 11.21576 from the top of the body / neck joint / 14th fret center to the top of the bridge plate.

I overlayed the brace pattern and the ouside body plan and discovered something that you should note-
the long lines of the bridge and bridge plate don't line up. This looks purpousefully done so that that the bridge pins center on the bridge plate ( on the bridge they are off the center line of the bridge of course ).

Also, top of body / 14th fret to center of x brace is 9.68794, top of body / 14th fret to center of soundhole is 6.12204.

If you want me to pull any other dimentions let me know.

How do you determine the X-brace angle from those plans? I'm surely overlooking something.

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Formerly known as Adaboy.......

I pulled the CAD file into Rhino and measured the x brace angle at 92.5 degrees.

Thanks everyone for the input on the plans and the thoughts on how to place the bridge plate.

With these two ideas in mind:





Todd's plan is closer to my idea of what should be happening. His idea follows closer to what I think I have observed others doing as apposed to what is represented in the plan. The plan is a representation of what Gibson was doing with this guitar in 1940. Is there and advantage\or disadvantage to following the plan exactly or to adapt the plan to follow Todd's practice here?

One area that I am having trouble with using this set of plans (but may not be that serious) is that I don't have exact point identified to locate additional braces. I have estimated where the T3 braces go. For the X brace I measured the angle from the plan. The plan provided a point to help locate the X. My placement is right in line with Snaglpuss and Charlie T's measurements so I'm doing Ok there.

What I’m not sure about is a reference point to locate the T3, T7, T8, and T9 braces. If I had a point off the X-brace I think I could measure the angle and get close.

John

John - I threw some measurements on the plan in Rhino to serve as references. Hopefully the photo is large enough to read. It would be easy for me to add additional measurements, so if there are some additional specific references you would like, let me know and I'll add them.

The angle of T7 to T5/6 is 92.49'
The angle of T3 to T5/6 is 71.42'
The angle of T8/9 to T6 is 69.92'
T8 & T9 are parallel
The two T3's are 2.598 apart on there inside edges where they hit T2

I forgot the measurements for T3. Added in this one......

Are you sure it wasn't 11.21575? (Sorry, being silly, couldn't help myself. Talking about splitting hairs ...

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Jim Kirby
kirby@udel.edu

I'll leave the rounding to you.

Obviously no one is working to this precision on a guitar.

If I'm working on a CAD drawing I always leave 5 decimals precision, that way if you end up adding
a whole slew of numbers you don't get jazzed at the end by adding a bunch of rounded numbers.

I can't tell you how many times at work I've added all the sub dimensions on a string and not had it hit the
overall dimension, especially when some draftman or designer leaves their drawing set up in fractions and rounding
to a 16th or 8th.

Yes, I really do apologize, I just couldn't help it. i do understand the problem of accumulated roundoff - I have to deal with it every day when grading people's homework problems. My bad ... (need an imoticom for subservience )...

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Jim Kirby
kirby@udel.edu

Thanks.

I think that gives me what I have been looking for.

My main concern with rounding is to keep it intentional.

It would be nice to see the dimensions from the neck block to: UTB, middle of soundhole, X-Brace intersection, and to front/back of bridge. The neck block to bridge dimension is fairly important and referencing all these dimension from the neck block (one source) would be better (my opinion only) than referencing some off the neck block and some off the tail block. (if your body length gets a little off, then the bridge plate location would likewise be a off if you locate it off the tail block)

Thanks for these dimensions!!!

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Formerly known as Adaboy.......

Darryl - that makes perfect sense. I assume I should measure from the side of the neck block closest to the sound hole as opposed to the side closest to the neck. Is that right?

Personally, I would reference everything from the outside of the bock........which gives the distance from the 14th fret ( or whichever fret joins the body). Then all the dimensions are tied in with the scale length. Just my thoughts.

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Formerly known as Adaboy.......

How's this Darryl? Let me know if you'd like me to add or change anything. I love Rhino!

That's great Charlie! Thanks for doing that.

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Formerly known as Adaboy.......

No problem Darryl.

Charlie,

Thanks for doing that. For mine I made my body a bit shorter and have been referencing everything from the 14th fret body joint.

These additional measurements really help in the decision making process for the brace layout.

John

What a timely thread! I just pulled down the plans for this guitar a couple of weeks ago and got a side bending mold from John Hall. Thanks for adding some measurements to the drawings, Charlie! I have a couple of other projects to finish up, but once done, I'd like to get an L-00 on the bench.

Ken

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