Making a custom radius gauge?

[Scott Lynch]

I am eagerly awaiting the arrival of a Yamaha BBP35 I recently ordered online. As I wait for it, I am curious about how to accomplish a good setup for this bass, particularly in getting the string heights properly radiused to the fretboard. Chances are this bass could play beautifully right out of the box, but I've found myself pretty picky about string height and gravitate toward 3/32" at the B and 5/64" on the G, with the three middle strings following the radius from there.

The Yamaha site publishes the BBP35 fretboard radius at 600 mm or around 23 5/8". Although I own a set of fretboard radius gauges, I don't have anything that flat.

How could I go about making a radius gauge that matches the arc of this fretboard? My thought is to just use a graphic design program to draw an arc using that specific radius, print it on a nice piece of paper such as card stock, then carefully cut along the line. Are there any (free) graphic design/drawing programs that could accomplish this task? I have an iMac.

Other ideas for getting a hold of a 600 mm radius gauge are welcome too, of course. Hit me with your thoughts - thanks!

 

[Dadum]

Here is a printable 508 mm radius gauge. No 600 mm but maybe close enough. At least it is an example to follow.

Radius Gauges — Haze Guitars

 

[boxerrider]

Here is one analog method for folks without trammel points - there are many variations.

• Lock a tape measure at 23 5/8".
• Hook the end on the corner of your dining room table.
• Tape a piece of paper (or card stock, cereal box, shoebox lid, etc.) on the table so that the center is 23 5/8" from the corner.
• Hold a pencil at the 23 5/8" line and swing the tape measure to draw an arc.

An entertaining way to pass the time waiting for your NBD - Enjoy!

 

[Willicious]

Unless I am missing something in your equation (very possible), why not establish string-to-fretboard-radius at your desired action using a StewMac String Action Gauge?
When I first got into doing my own setups, I bought into the understring radius gauges, until I went with the SAG and it's so much easier and more accurate.
6/64" for that B, 5/64" for E, etc. to taste. Regardless, enjoy the heck out of that Yamaha.

 

[kgbeast]

Libre CAD can do this easy and it has facility to print true 1:1 scale on a regular printer. As with any cad however, if you just download it out of blue for the first time using something like that, you will struggle to draw a circle, let alone print anything to scale. But there are plethora of instructional videos on YouTube. I can draw this up and post here as pdf if you need it still.

 

[kgbeast]

Also, you can buy from Amazon French Curve Ruler
The one that has concaved curve, the device looks like a large plastic comma. You can then hold it against the fretboard, find the section of the curve that fits right and cut it out with hacksaw.

Other method that a bit more involved, is to tape one of the frets with masking tape, create a tape pocket and fill it with epoxy... Wait over night and you have a rigid curve if you mix the epoxy right... I would stick to French Curve though.

 

[Scott Lynch]

Unless I am missing something in your equation (very possible), why not establish string-to-fretboard-radius at your desired action using a StewMac String Action Gauge?
When I first got into doing my own setups, I bought into the understring radius gauges, until I went with the SAG and it's so much easier and more accurate.
6/64" for that B, 5/64" for E, etc. to taste. Regardless, enjoy the heck out of that Yamaha.

This seems like a viable alternative and if done correctly, could eliminate the need for a radius gauge altogether. I use a SAG tool to set the B and G heights, but then what? How do I properly set the middle strings, i.e. 5.25/64 for the D, 5.5/64 for the A, and 5.75/64 for the E?

 

[kgbeast]

This seems like a viable alternative and if done correctly, could eliminate the need for a radius gauge altogether. I use a SAG tool to set the B and G heights, but then what? How do I properly set the middle strings, i.e. 5.25/64 for the D, 5.5/64 for the A, and 5.75/64 for the E?

Problem with this method is the spacing will be from the bottom of the string, not top, unless you add to compensate for string gauge difference. I was assuming you were looking for outside curve.

 

[Willicious]

This seems like a viable alternative and if done correctly, could eliminate the need for a radius gauge altogether. I use a SAG tool to set the B and G heights, but then what? How do I properly set the middle strings, i.e. 5.25/64 for the D, 5.5/64 for the A, and 5.75/64 for the E?

I'd say stick with 64ths, and don't overthink / split them. Your fingers will not discern fractions of a 64th.
A common B string action is 6 or 7/64, 5/64 for EAD, and if your fretwork is good, 4/64 for your G. All to taste.
I just play a standard 4-string P, with pretty dialed-in fretwork, and set mine at 4/64 across all four strings.

 

[redname]

I am eagerly awaiting the arrival of a Yamaha BBP35 I recently ordered online. As I wait for it, I am curious about how to accomplish a good setup for this bass, particularly in getting the string heights properly radiused to the fretboard. Chances are this bass could play beautifully right out of the box, but I've found myself pretty picky about string height and gravitate toward 3/32" at the B and 5/64" on the G, with the three middle strings following the radius from there.

The Yamaha site publishes the BBP35 fretboard radius at 600 mm or around 23 5/8". Although I own a set of fretboard radius gauges, I don't have anything that flat.

How could I go about making a radius gauge that matches the arc of this fretboard? My thought is to just use a graphic design program to draw an arc using that specific radius, print it on a nice piece of paper such as card stock, then carefully cut along the line. Are there any (free) graphic design/drawing programs that could accomplish this task? I have an iMac.

Other ideas for getting a hold of a 600 mm radius gauge are welcome too, of course. Hit me with your thoughts - thanks!

I had this issue but then I just got those gauges with markings to measure string heights and just measure the strings individually, this will produce the arc tht u'll need

 

[96tbird]

The neck is already radiused. If you set all strings to the same height off the fretboard, your radius will be spot on

However you actually don’t want all strings the same height do you? You usually want your G lower than the E So if they aren’t the same height the radius will not be true to the neck!

Radius gauges for setup are a complete waste of time. YMMV.

Just read the setup guides in the stickies section here and don’t worry about minutiea items like gauges that really do nothing useful.

I understand your wish to have perfection so just set each string the same height and radius will be perfect… you may not end up with perfect playability by having a perfect radius unless each fret is perfect.. we have a bunch of variables involved that perfection of one likely causes an issue on another variable.

 

[202dy]

You press the string down. The string contacts the fret. So the important measurement is fret to string.

Your fingers (brain!) will compensate for irregularities in finger to string (finger to "top" of the string) contact.

TL,dr: String radius is set from the bottom of the string.

Unless you like chasing buzzes when doing a set up.

 

[Turnaround]

My thought on making a radius gauge - don't. It's not really useful.

I've gone through this before but ai will do it again. In the diagram below, the two arcs are the same radius, spaced apart like plane of your strings (green) and the fretboard (red). Notice that the space between the arcs is greater in the centre than the ends. So if you use a radius gauge to set your strings that's the same radius as your fretboard, your A and D strings will be unnecessarily high.

Best to measure your string height from the fretboard with a rule or a feeler gauge.