Musings

I should be in the garage re-assembling Worm's outboard motor.

I should be in the garage making better rowlocks for Worm.

I should be in the garage.

Funny how centering some text makes one feel like a poet.

I am (sort of) working out the scantlings for Robinetta's new gaff. I started by googling. A forum post led me to Skene's Elements of Yacht Design. Google books has a searchable version and I'm working through the hits on gaff in the book. There are lots of sums and I really want to understand how they apply. On the other hand, the most relevant text is 'The loading of booms is almost impossible to determine and reliance may be placed on the proportions indicated in the diagram.' The diagram says a solid gaff should have a max diameter D = 0.02 times its length. The peak end diameter should be .75 D. The throat diameter should be .93 D. Skene goes on to say 'If the boom or gaff is to be made hollow, a section may be used having the same ratio as that of a circle of diameter indicated for the solid spar.' And there is an equation. I'm going to see if I can get the equation into this blog. Earlier in the book there is some maths about hollow spars. I'll get to that but I'm currently distracted by another hit I got when searching for Skene's book.

One link took me to a review of Skene by Tom MacNaughton. I've not come across him before but he's a Naval Architect in Maine. His website is wonderful and I got completely waylaid by the text on his Yacht Design School. In the FAQ there is a question 'What kind of designs are most often requested?' The answer is this lovely list:

1. Ones too large for the customer to afford.
2. Once with too many features to pack into the requested size.
3. Overly complicated ones.
4. Ones with features incompatible with the chosen service. (Mostly commonly overly shoal boats for offshore use.)
5. Ones that sacrifice good performance to chase fashions that are confused with technological advances.
6. Ones that sacrifice appearance and investment value to ill conceived fashion.
7. Ones for production boat builders who refuse to commit to even minimally safe scantlings.

Cool huh?