Bass building

[kaoskater08]

Hey guys,

I want to build my own 6 string bass and need some suggestions. I have slightly larger hands/long fingers and like the string spacing of a 4 string but every 6 string I have played has narrower strings than what I want. What is a good way to go about figuring out the right neck dimensions (width at nut and width at 24th fret) in order to get that spacing? I've built one instrument before but it was pretty much just a copy of the 4 string I currently have so I don't have anything go to off of like before.

[devo_stevo]

a ruler, straight edge, and a pencil should get you what you need. Get a big piece of paper and start drawing it all up full size. From that, you get your dimensions and it gives you a good idea of the proportions and scale of things. I think that there are some threads that cover how to do a lot of this in the stickys or by searching here, but this should get you started.

Good luck.

[HaMMerHeD]

Just in case you weren't already aware...

Most four strings are spaced at 19mm (0.75") on center from string to string, and most six strings are close to 16.5mm (0.65"). If you want 4-string style spacing all the way down the board, you'll need to cut your own nut, since most commercially available pre-slotted 6-string bass nuts are narrower than most commercially available pre-slotted 4-string nuts.

Cutting the nut is pretty simple. A precise ruler, a nut blank of your material of choice and a set of needle files will get it done.

[Big B.]

Originally Posted by HaMMerHeD

Just in case you weren't already aware...

Most four strings are spaced at 19mm (0.75") on center from string to string, and most six strings are close to 16.5mm (0.65"). If you want 4-string style spacing all the way down the board, you'll need to cut your own nut, since most commercially available pre-slotted 6-string bass nuts are narrower than most commercially available pre-slotted 4-string nuts.

Cutting the nut is pretty simple. A precise ruler, a nut blank of your material of choice and a set of needle files will get it done.

I see fewer narrow spaced sixers like that than I used to. Seems more common on production models, the soundgear sixes come to mind, while a lot of the custom builders seem to go with a wider spacing unless specifically asked for the narrow spacing. I played a fretted anjd fretless Roscoe six for many years and the spacing was 18mm which I found to be just right. Most of the high end sixes I've played were in that ballpark as well. If you really want to examine a wide spaced six check out the Yamaha TRB sixers. From what I recall they are spaced very close to standard Fender 4 string spacing.

[HaMMerHeD]

Yeah, the 6-string fretless I am building is getting 18mm spacing, and the 5-string is getting 19mm spacing.

I was referring to mass produced instruments having narrow spacing.

[Big B.]

Originally Posted by HaMMerHeD

Yeah, the 6-string fretless I am building is getting 18mm spacing, and the 5-string is getting 19mm spacing.

I was referring to mass produced instruments having narrow spacing.

Yeah, I have a neck I built for a customer with an older production 6. The original got broken and I was asked to build a replacement. Its so narrow that I cant imagine 6 strings really being playable. Its the same width as my standard 5 string neck. Probably not a coincidence that many production sixers are about the same width as their 5 string.

[kaoskater08]

Thanks for the responses guys! This is my first true "custom" build so I'm trying to get it right the first time.

One more question...is there a general rule for the spacing between the outer strings and the edge of the neck, or is it just the string spacing measurements?

i.e. for 4 string (19mm) space between the edge of the neck and the E string is 19mm?

[devo_stevo]

Typically about 1/8" from the edge of the neck and the edge of the string is enough.

[HaMMerHeD]

No, 19mm would be just the spacing between strings on center at the bridge.

As far as spacing between the outer strings and the edge of the neck, you can use whatever you feel comfortable with. Obviously you don't want the strings to be falling off the neck, so you do need a certain amount of space.

I'll show you how I plan it in just a minute.

[HaMMerHeD]

OK, here goes.

First, I take the dimensions from the nut I plan to use. In this example case, it's a GraphTech PT-1200-00 4 string bass nut. From Graphtech's side, you can do a little math and see that the distance from the center of the outermost nut slots to the end of the nut is 5mm. You don't really want your neck to be wider than the nut, so assuming you don't modify the nut, this will be the distance from the centers of the outer strings to the outer edges of the fingerboard.

To begin my designs, I start with the nut in my cheapo CAD program.



The lines just inside the outer box represent the "E-to-E" spacing given by graphtech on their site. In the case of this nut, it is 1-7/32".

Then I draw a line perpendicular to the nut. In this example, I'm using a 34" scale with 19mm string spacing at the bridge.

Then I draw a 57mm (19mm * 3) long line representing on-center string spacing at the bridge, at the bottom of the 34" scale line, parallel to the nut and perpendicular to the scale line. This is the witness line. It looks like this:



Then I draw a line connecting the outer string notches on the nut to the ends of the witness line drawn at the bottom. These lines represent the E and G strings on this 4-string bass.



From there it's a very simple process of copying and pasting the string lines, and attaching them to the outer corners of the nut.



To complete the fingerboard design, I multiply the scale length (34") by 0.75 to get the position of the 24th fret. That gives me 25.5". To that, I add 0.25" so that there is enough space after the last fret for the end of the fingerboard, giving me 25.75". I then add a line parallel to the witness point exactly 25.75" from the nut, giving me the end of the fingerboard. Last, I delete the string lines and trim the line representing the end of the fretboard to be the exact width of the fretboard, and the core of the design is complete.



From there, I continue with the design for the rest of the bass, adding curves and lines and spaces for hardware.

One of the nice things about this software is that I can get dimensions on just about anything very easily. All I have to do is draw a line connecting 2 points, and the software tells me exactly how long it is. I can also specify particular dimensions for any given line. For example, to create the 34" scale line, I drew a short line at 270 degrees (down), then clicked the length box and entered 34", and it adjusted for me.

[kaoskater08]

Thanks for the information! What CAD program do you use?