August 2006
The objective of the new drive was to create a more rugged pivot, to create a fairing for the submerged leg, to use non-cycling tubing so sizes are not limited, and to use all aluminum/bronze/stainless to avoid water tight seals and hopefully cut some weight.
After testing the drive, I was still not happy with the steering, mostly because the addition of the fairing to reduce drag actually increased the drag anytime the propeller was angled. I locked out the steerable prop and added a rudder. It was a fun experiment, but in the end, the old fashioned way performed much better.
September 2006
v2.1 I attempted to fabricate a new prop sized for a lower cadence ratio hoping to gain a little efficiency. With some design help from a fellow HPB enthusiast, I gave it a try and was quite happy with the results.
HPB Drive v2 Build
Aluminum pivot replaces cracked wooden one
Bottom bracket mount
Bottom bracket pivot assembly
1/8” plywood fairing
Glassed fairing
Upper leg assembly
Lower leg assembly
Complete assembly
Epoxy coat on the rudder
Rudder assembly
Rudder position (riderless waterline)
Partially tilted up for beaching
Twisting one section
Checking for bending
Checking perpedicularity
Checking gaps with other blades
Pitch block weld fixture
Second blade setup
Finished welding
Finished grinding/sanding
Assembled on existing drive leg
