Gibson "rule of 18" rosewood fret board

Silvertone

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Gibson has changed their scale lengths over the years. Most just call it 24.75" but very few were actually 24.75". They have used 24 5/8" (24.625"), 24 9/16" (24.563") and "rule of 18" which is a scale developed with a different algorithm to most modern scale calculations. Unfortunately, if you would like to make a replica of a late 50's early 60's Gibson that is the scale that they used. A friend of mine is building a replica of a 59 Burst for himself and I am supplying a fret board.

So where to get the individual fret spacing? I was lucky enough to hook up with Tom Bartlett, an awesome luthier, that is very knowledgeable about those guitars. I've known Tom for about 10 yrs now and work with him quite a bit whenever he needs CAD help. Tom sells construction drawings for a few different models of vintage Gibson guitars. One of which is the 59 Burst. I helped him update his drawings. These drawings have a chart and dimensions for the fret board in question, so I will start there.

Toms 59 replica drawings -

small-plans.jpg

I'll take those drawings and recreate, and double check fret spacing, to create my fret board plans.
rule of 18.JPG
Once I confirm the dimensions and spacing. I import it into my CAM program , Fusion 360, and create the tool paths to turn the blank into a fret board.

rule of 18 - fusion.JPG

I create five tool paths to finish the board and save them out to a memory stick. I number and name them so I cut them in the correct order and use the correct size bit.

toolpaths.JPG

My friend has already picked out a fret board from my stock of Madagascar rosewood boards. BTW the boards on those vintage guitars were Brazilian rosewood, which is very scarce to get these days and also very complicated to obtain paperwork to ship internationally. My friends lives in the USA so we picked out a board that looks similar in colour and grain. I do have a few Brazilian rosewood boards in my possession so I try and pickup other rosewood species with a similar look for these fret boards. Here is a pic of three fret boards. Two are Brazilian and the other is the board I will be cutting.



IMG_1909.jpg
Once I clean off my CNC machine and get it all setup, I will be ready to cut some sweet smelling wood. :dude:

Cheers Peter.
 

donepearce

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Gibson has changed their scale lengths over the years. Most just call it 24.75" but very few were actually 24.75". They have used 24 5/8" (24.625"), 24 9/16" (24.563") and "rule of 18" which is a scale developed with a different algorithm to most modern scale calculations. Unfortunately, if you would like to make a replica of a late 50's early 60's Gibson that is the scale that they used. A friend of mine is building a replica of a 59 Burst for himself and I am supplying a fret board.

So where to get the individual fret spacing? I was lucky enough to hook up with Tom Bartlett, an awesome luthier, that is very knowledgeable about those guitars. I've known Tom for about 10 yrs now and work with him quite a bit whenever he needs CAD help. Tom sells construction drawings for a few different models of vintage Gibson guitars. One of which is the 59 Burst. I helped him update his drawings. These drawings have a chart and dimensions for the fret board in question, so I will start there.

Toms 59 replica drawings -

View attachment 47256

I'll take those drawings and recreate, and double check fret spacing, to create my fret board plans.
View attachment 47258
Once I confirm the dimensions and spacing. I import it into my CAM program , Fusion 360, and create the tool paths to turn the blank into a fret board.

View attachment 47257

I create five tool paths to finish the board and save them out to a memory stick. I number and name them so I cut them in the correct order and use the correct size bit.

View attachment 47259

My friend has already picked out a fret board from my stock of Madagascar rosewood boards. BTW the boards on those vintage guitars were Brazilian rosewood, which is very scarce to get these days and also very complicated to obtain paperwork to ship internationally. My friends lives in the USA so we picked out a board that looks similar in colour and grain. I do have a few Brazilian rosewood boards in my possession so I try and pickup other rosewood species with a similar look for these fret boards. Here is a pic of three fret boards. Two are Brazilian and the other is the board I will be cutting.



View attachment 47260
Once I clean off my CNC machine and get it all setup, I will be ready to cut some sweet smelling wood. :dude:

Cheers Peter.

My CNC is at last able to cut fret slots. I bought a new 1.5kW spindle motor that does 30,000 RPM. It's like a knife through butter. At the same time I massively stiffened all the axes and eliminated backlash. All is now good in CNC land.
 

Silvertone

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I have no problem cutting fret slots at 24k rpms, which is the maximum for my 3hp spindle. I would say the rigidity is the important part with such small end mills. I just cut this board and have used the same cheap 0.024" bit for about 20 boards now. I also outline the inlays on most of my boards with the same bit.

Slotted and tested inlay fit -
IMG_1960-lo.jpg

Cheers Peter.
 

MR D

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Gibson has changed their scale lengths over the years. Most just call it 24.75" but very few were actually 24.75". They have used 24 5/8" (24.625"), 24 9/16" (24.563") and "rule of 18" which is a scale developed with a different algorithm to most modern scale calculations. Unfortunately, if you would like to make a replica of a late 50's early 60's Gibson that is the scale that they used. A friend of mine is building a replica of a 59 Burst for himself and I am supplying a fret board.

So where to get the individual fret spacing? I was lucky enough to hook up with Tom Bartlett, an awesome luthier, that is very knowledgeable about those guitars. I've known Tom for about 10 yrs now and work with him quite a bit whenever he needs CAD help. Tom sells construction drawings for a few different models of vintage Gibson guitars. One of which is the 59 Burst. I helped him update his drawings. These drawings have a chart and dimensions for the fret board in question, so I will start there.

Toms 59 replica drawings -

View attachment 47256

I'll take those drawings and recreate, and double check fret spacing, to create my fret board plans.
View attachment 47258
Once I confirm the dimensions and spacing. I import it into my CAM program , Fusion 360, and create the tool paths to turn the blank into a fret board.

View attachment 47257

I create five tool paths to finish the board and save them out to a memory stick. I number and name them so I cut them in the correct order and use the correct size bit.

View attachment 47259

My friend has already picked out a fret board from my stock of Madagascar rosewood boards. BTW the boards on those vintage guitars were Brazilian rosewood, which is very scarce to get these days and also very complicated to obtain paperwork to ship internationally. My friends lives in the USA so we picked out a board that looks similar in colour and grain. I do have a few Brazilian rosewood boards in my possession so I try and pickup other rosewood species with a similar look for these fret boards. Here is a pic of three fret boards. Two are Brazilian and the other is the board I will be cutting.



View attachment 47260
Once I clean off my CNC machine and get it all setup, I will be ready to cut some sweet smelling wood. :dude:

Cheers Peter.
NICE ONE !

I'm glad to see you acknowlegde the 'Rule of 18', Pythagoras work for the ages. A work that benefits all musicians..... was published(?) around about 3,000 years ago. The 'RULE OF 18', although I have never read the entire work, is the basis of just about all scales on stringed instruments in use in the Western World today....Pythagoras, that frikkin Guy was a walkin talking computer...all the way back then (600 BCE?)

Most luthiers I have ever questioned on the matter say that GIBSON actually figured out the MATH in-correctly (and consequently have problematic 'G' strings) when they figured out the 24.75" length....and it actually took some years to figure out their mistake. Of course, GIBSON could never publicy acknoweldge the error (for financial reasons ?)....so they just quietly changed the lengths and publish the specs...IDK how true all of this is but I could definitely believe GIBSON somehow figured out the MATH wrong.
 

chilipeppermaniac

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Gibson has changed their scale lengths over the years. Most just call it 24.75" but very few were actually 24.75". They have used 24 5/8" (24.625"), 24 9/16" (24.563") and "rule of 18" which is a scale developed with a different algorithm to most modern scale calculations. Unfortunately, if you would like to make a replica of a late 50's early 60's Gibson that is the scale that they used. A friend of mine is building a replica of a 59 Burst for himself and I am supplying a fret board.

So where to get the individual fret spacing? I was lucky enough to hook up with Tom Bartlett, an awesome luthier, that is very knowledgeable about those guitars. I've known Tom for about 10 yrs now and work with him quite a bit whenever he needs CAD help. Tom sells construction drawings for a few different models of vintage Gibson guitars. One of which is the 59 Burst. I helped him update his drawings. These drawings have a chart and dimensions for the fret board in question, so I will start there.

Toms 59 replica drawings -

View attachment 47256

I'll take those drawings and recreate, and double check fret spacing, to create my fret board plans.
View attachment 47258
Once I confirm the dimensions and spacing. I import it into my CAM program , Fusion 360, and create the tool paths to turn the blank into a fret board.

View attachment 47257

I create five tool paths to finish the board and save them out to a memory stick. I number and name them so I cut them in the correct order and use the correct size bit.

View attachment 47259

My friend has already picked out a fret board from my stock of Madagascar rosewood boards. BTW the boards on those vintage guitars were Brazilian rosewood, which is very scarce to get these days and also very complicated to obtain paperwork to ship internationally. My friends lives in the USA so we picked out a board that looks similar in colour and grain. I do have a few Brazilian rosewood boards in my possession so I try and pickup other rosewood species with a similar look for these fret boards. Here is a pic of three fret boards. Two are Brazilian and the other is the board I will be cutting.



View attachment 47260
Once I clean off my CNC machine and get it all setup, I will be ready to cut some sweet smelling wood. :dude:

Cheers Peter.

Thank you for teaching me my thing I needed to learn today. My reason I woke up and opened my brain.
 


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