I am going to build an upright bass. Does anyone have plans or information that may help especially with scale length, tuning machines, use of piezo and any other helpful information? If you can point me in the right direction it would be a help e.g. stings, neck dimensions
I have decided on a hybrid acoustic / electric double bass with the fret board tilting back at about 20 degrees.
I have a few questions
1 What strings are best to use. I am thinking of a 3 or 4 string model. I believe that weed eater line (grass trimmer) line can be used. If so what size or is there an alternative
2. Can normal guitar machine heads be used with the holes reamed out?
3 Is it easier to play than a CBG because I am struggling to learn the CBG
4 Any other help or tips
5 Are both the bridge and nut made out of wood?
Hey Redbelly, I built one of these based on Dennis Havlena's design.
Scale length is 40"
1. I used weed whacker strings .080, .095 and.105 inches for the G, D, A strings and it works well, but as he says in the article the low E was another matter. I think I used .120" I have yet to try it, but he suggests using vinyl coated clothes line for the E string. Basically, I just use it as a 3 stringer, or tune the low E up to G. Either way, the whacker line is really floppy and quiet compared to the other strings, so I barely use it.
2. I used normal guitar tuners reamed out and it has worked great. The only problem I had was making sure the guitar tuners were de-burred after I drilled them out. The trimmer line cuts very easily when brought up to tension and I broke a couple strings before I filed the holes down.
3. Playing without frets can be tough. I used thumbtacks as position markers on the side of the neck. On the other hand, there are fewer notes to worry about, so I'd say it's a little easier. I don't practice enough with the bass.
4. I used 1/4" ply for the soundboard, if I were to do it again, I would like to try a door skin - about 1/8" with some bracing for (hopefully) a better acoustic sound, but this is just speculation. I'm not so sure it would be worth the trouble for a few more dB. I started with a disc piezo and soon switched to a rod that I salvaged from a cheap acoustic bass and my amplified sound was sooooo much better.
5. My bridge is made from a cutting board and the nut is a piece of maple. Again, I'm sort of guessing here, but I don't think the nut material matters very much with this design. I made mine with a flat fretboard, so I had to angle the bridge to make sure the thicker strings had enough room to vibrate as you can see here.
Thanks very much for your information. Could you please explain what a sound post and bass bar are for and where do you place them
Well, I'm not really sure what they do - I was just following instructions ;) I'm assuming the bass bar helps sort of focus the lowest frequencies across the sound board. I installed it parallel with the low string about an inch or two away, but this was before I played it so I'm not sure if it is necessary. My gut says yes. The sound post is installed an inch or so below the bridge on the high string side. It's cut just a hair longer than the depth of the tub, so when the top is screwed down, the whole thing tensions up nicely.
I tried it with and without the sound post and can say it made a difference. It helps give the top some support and connects the top to the washtub, allowing the sound to resonate down the post to the tub. Without the post, it is muddy and loose, but with the post the sound is tighter, especially the D and G strings.