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  #1  
Old 04-29-2017, 11:28 PM
ChalkLitIScream ChalkLitIScream is offline
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Default Putting a radius on a saddle

I have a blank pre radiused Tusq saddle which is 14", but Id like to first shape it to 16" before I modifiy it further.
Other than purchasing a sanding block, how else is one able to sand down and put a specific radius on the thin saddle?

In my mind, Ive thought about putting a piece of sandpaper on the fretbord which has the desired radius. Then sand down the bottom of some piece of material. From there, attach sandpaper to the now sanded bottom of the material, and then use tha as a sanding block of sorts.

Any suggestions?
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Old 04-30-2017, 11:48 AM
M Hayden M Hayden is offline
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Use a foam core nail file from the drugstore, as they're slightly flexible.

1. Place the nail file on a flat surface and taper the ends a bit,
2. Put the saddle into the slot and sight down the neck to look at the taper vs the frets
3. String it up and measure string height, keeping in mind that bass strings need to be higher than treble strings bc of the string excursion
4. Remove, adjust, retest until done.

Remember that the nail file can also help compensate the string length a bit, depending on where you file the crown of the saddle for a particular string. I usually compensate 1 in the middle of the saddle width, 2 pretty far back, and 3-6 at an angle from the front to the back.
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Old 04-30-2017, 12:24 PM
Sperry Sperry is offline
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Quote:
Originally Posted by M Hayden View Post
Use a foam core nail file from the drugstore, as they're slightly flexible.
Micro-Mesh Sanding Sticks ??

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Old 04-30-2017, 12:39 PM
murrmac123 murrmac123 is offline
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You are approaching the whole problem donkey-backwards (or maybe the other word for donkey, which will get censored...)

There is , ideally, no such thing as a saddle top radius. You need to sand the bottom of the saddle dead flat, and then file the top of the saddle from the top, in situ, to get the desired action for each individual string

You then merge, by sanding, the flats so created to give you a smooth curve. This curve, however, is never a "radius".

To give the correct profile for the top of the saddle, the way to do it is to use the semicircular notches on a utility knife blade ... use these notches as a scraper, and you will have a lovely semicircular profile in no time.
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Old 04-30-2017, 12:44 PM
Frank Ford Frank Ford is offline
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Quote:
Originally Posted by ChalkLitIScream View Post
Any suggestions?
Don't overthink it. If you MUST have a specific radius, just draw an appropriate arc on a piece of paper, and take a bit off the saddle slowly until it matches.
Remember the goal is good playability, not precision of measurement of specific parts. I often modify the radius or arc of the saddle to achieve the relative string action I want, without actually considering what the actual radius turns out to be.
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Old 04-30-2017, 04:39 PM
Ned Milburn Ned Milburn is offline
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Hold your saddle blank at the fingerboard end and with a pencil (sliced in half if necessary) scribe a line on the saddle blank. This is a really good start, simple as could be, quick, and you don't have to guess your guitar fretboard surface radius.
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Old 04-30-2017, 04:49 PM
murrmac123 murrmac123 is offline
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Quote:
Originally Posted by Ned Milburn View Post
Hold your saddle blank at the fingerboard end and with a pencil (sliced in half if necessary) scribe a line on the saddle blank. This is a really good start, simple as could be, quick, and you don't have to guess your guitar fretboard surface radius.
Not on steel string acoustics, Ned.

For optimum playability , the D and G strings will always be lower than the method you describe.
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Old 04-30-2017, 06:26 PM
mirwa mirwa is offline
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Quote:
Originally Posted by ChalkLitIScream View Post
I have a blank pre radiused Tusq saddle which is 14", but Id like to first shape it to 16" before I modifiy it further.
Other than purchasing a sanding block, how else is one able to sand down and put a specific radius on the thin saddle?
Without the right tools it does make one think outside the square.

Take a paint program and draw a 16inch radius, cut a section of the circle away and print that to scale, then you can overlay your saddle to the picture and sand away accordingly.

Steve
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Old 04-30-2017, 06:28 PM
mirwa mirwa is offline
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Quote:
Originally Posted by Ned Milburn View Post
Hold your saddle blank at the fingerboard end and with a pencil (sliced in half if necessary) scribe a line on the saddle blank. This is a really good start, simple as could be, quick, and you don't have to guess your guitar fretboard surface radius.
Good idea, this is exactly what we do when marking out a violin / cello or dbl bass bridge.

Perfect shape first go.

Steve
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  #10  
Old 04-30-2017, 10:58 PM
Ned Milburn Ned Milburn is offline
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Quote:
Originally Posted by murrmac123 View Post
Not on steel string acoustics, Ned.

For optimum playability , the D and G strings will always be lower than the method you describe.

Quote:
Originally Posted by Ned Milburn View Post
Hold your saddle blank at the fingerboard end and with a pencil (sliced in half if necessary) scribe a line on the saddle blank. This is a really good start, simple as could be, quick, and you don't have to guess your guitar fretboard surface radius.
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  #11  
Old 05-01-2017, 01:08 AM
Monsoon1 Monsoon1 is offline
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Quote:
Originally Posted by mirwa View Post
Without the right tools it does make one think outside the square.

Take a paint program and draw a 16inch radius, cut a section of the circle away and print that to scale, then you can overlay your saddle to the picture and sand away accordingly.

Steve
That's pretty good.
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  #12  
Old 05-01-2017, 05:02 AM
Sperry Sperry is offline
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To get an idea of where I stand on a fiddle I use the projected height. A straight edge with end graduations along the fingerboard, and the bridge positioned where it goes. I'll get the bridge to within a millimeter or two of where I want it.

But in the end, the strings are on, and I'm measuring string height over the fingerboard, then lowering (I hope, 'cause I can't raise the string) the bridge as required.

On a guitar, I'd probably string it up first and see what's what.

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Old 05-01-2017, 06:45 AM
jonfields45 jonfields45 is offline
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I sold my T5z because the electronics were unreliable and had to be fixed...over and over.

My other gripe was acoustic string spacing at the saddle combined with a tighter fretboard radius than the regular T5 put the high E string much lower than the B. If you did an electric style full step stretch of the high E above the 14th fret, it would fret out at any reasonable action setting (I made tilted shims rather than making a new saddle). So maybe slavish attention to the fretboard radius is not always the best solution.

That guitar's next problem was the bridge pickup height could not be set close enough to the now higher high E and B strings to do its rock-and-roll duty properly. I did not try re-shimming the neck to see if a shallower neck angle would lower the fretboard over the body (past the 14th fret) but I assumed it wouldn't. Was that the right assumption? I restored it to factory spec (no saddle shim and lowered the bridge PU treble side) before selling it.
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Last edited by jonfields45; 05-01-2017 at 04:05 PM.
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