Saturday, July 28, 2012

Ready to enjoy

Well, the past few weeks have involved building and then working a few bugs out of the new gearbox.  It is a 6.5 ratio using two stages (chain then bevel gear) of the design shown earlier.

It is installed on the boat and I have had a few outings.  I have been trying to tweak the chainline and a few other things to decrease what seemed to be more noise than I was expecting.  I haven't done a full sprint, but it has held up to brisk cruising.

The new prop from Rick is also on and this was  designed for the new gear ratio.  Rick has a mold for steel core, carbon fiber blades, and he is able to adjust the pitch somewhat to accommodate various boats by changing the root angle in the folding blade hub design.  For me cruising has been about 5.5-6 mph at about 72-78 rpm, and I find this to be quite comfortable.  Tiring but sustainable for an outing.

Everything is back together and I have also built a new dolly for walking to the lake.  The boat is balanced with maybe 10lbs to hold at the stern.  I need to watch for potholes, but so far it is going without incident.  I have met a lot of people who are really interested in hearing what it is all about.

I would say I am still quite pleased with the result.  I would also say that now that I have indulged my fascination with steerable props, I would be very happy to go towards a simpler drive design.  I am thinking of tackling an ultra light weight version next, whenever that might be.  Two boats is never enough.