Presure box 2

The take up spool is moved allong by the crank shaft. It was constructed with a piece of drain pipe with two wooden incerts at each end. It then had wooden cheeks attached at either end to keep the music in line.

The first time I made it slightly too short so I sanded on the the cheeks back down to make up the extra space. I found a new tool on the band saw for cutting out circles. Amazing.

All the moving parts in the pressure box spin on axis's. The axis's need to be supported properly over wise over time they will slowly make larger and larger holes in the sides of the presure box. Or they will brake all together under the strain.

It took me a long while to figure out what bearing blocks were. I had no idea from the diagram I had. Eventually I relised they were simply hard wood blocks with holes in. They where recomended to be drilled in half so that you cound dismantle them when nessassary to make repairs. I diseided to take the design one step further and add metal bearing blocks inside to strengthen the bearing blocks and ensire the axsis turn correctly. Small holes could be drilled in the top of wooden bearing blocks to allow for oil to be put in. Or you can use graphite powder to reduce squeeking. All bearing blocks need to be placed accuratly to ensire smooth working.