A few summers ago, I decided to try to make an upright bass. After building one using a tin bucket as the body (from a blueprint I found online) I was disappointed with the lack of volume and poor tone, so I thought I would try again with a wheelbarrow as the body.
Unfortunately I did not take pictures of the process of building my wheelbarrow bass, but I will try to describe the process as best I can by focusing on each part of the instrument, and including rough diagrams. I did as best as I could to describe what I did, but it has been awhile since I finished this project so I'm probably glossing over a great deal...
**I must admit the idea to use a wheelbarrow is not completely original, as I have seen at least one video of an upright made from a wheelbarrow online...but oh well here is my take on the concept!
Step 1: An Overview...
The wheelbarrow I used as the body is a large metal True Value wheelbarrow. I used 1/4" plywood as the front cover, and I made the neck out of three separate 1/2" planks glued together. The bridge and the fretboard are made of 1/2" thick maple.
For the tuning pegs, I just used standard Fender electric bass tuners. The strings are actual upright bass strings, but they were super cheap (I ordered a couple sets from China for about $20 a set). As an alternative, you can use weed whacker line for the strings, as it comes in the correct gauges as bass strings! The weed whacker line gives the bass a nice "gut" tone.
I used a heavy application of black stain for all the wooden parts but I used lighter stain for the fretboard and bridge, and for the body I used black spray paint.
For some perspective on its size, I included a picture of me playing it, and the upright next to a standard size electric bass. Also pictured is a diagram (not to scale) showing some of the approximate dimensions of the bass.