# TWO FORMULAS

I am now sandpapering the  stow hatches below the bed. In a few places there is a inside radius. For that I have winded sandpaper around a stick. I use tejp with adhesive on both sides. Winding it 45degrees to the axis. To calculate the with of the sandpaper strip I came upp with the following formula

pi times diameter divided by the square root of two

The diameter of my stick is 15 mm hence the with of the strip 33 mm

The lenght of the strip is lenght of strip times the square root of two

A composite boatbulder often do windings to create or reinforce spars or cover with leather for example so it has general

Below a pictureof me using sthe sandpaper stick

To be continued…

Regards Yrvind