Re: Flexofold Prop
Another consideration: On KAIMI we have a 4 BLADED VARIPROP "BLUE WATER" MODEL. This "unboxing video" shows the shape and operation of the prop and its SIZE. Ours is a DF112 as well https://www.youtube.com/watch?v=C3RvbX1Oa54
After operating it for over 4 years I am sold on it. Its reverse seems as powerful as its forward force. Solid power in fwd or rev from a dead stop or at slow speeds. In motoring or motorsailing it provides good, fast propulsion and during sailing very little drag. Easy prop removal and bomb proof attachment to the shaft--see brochure. Seems well matched to the Amel with good cruising speeds from 1600-2700, quite a bit of our cruising motoring is up and down from 2000 It will let you go above 3200 with no problem--can't remember how high it goes. It seems to like motor sailing as well when there is lower load for a given rpm. Works well with our shaft brakes. The German based company will immediately respond to emails or phone calls. http://www.spw-gmbh.de/en/features-of-the-variprop.html also http://www.spw-gmbh.de/en/variprop-2-3-and-4-blade.html
2 Years in the water (boat is presently on the hard) and no need to change the prop nose cone zinc (or our rudder zincs), perhaps due to a galvanic isolator.
A video on their site is informative https://www.youtube.com/watch?time_continue=22&v=-CqLFaM3qvc If you look at the design in action you can see why it is powerful in both fwd and rev, why it has a lot of blade and why it has low drag when feathered.
"4-Blade-Power — the VARIPROP 'Blue Water'
Especially in blue water conditions, excessive blade loading causes cavitational noises, bubbles on blades and resulting loss of power, just when you need it most in the trough.
The solution is the VARIPROP 4-Blade — to-date worlds most modern 4-blade feathering propeller, with 30% larger blade areas, less blade loading, much greater thrust and undiminished power."
They are worth a call at least I think. They will definitely have our 2004 SM Redline on file (Yanmar).
Bob and Suzanne, Colorado
KAIMI SM 429, Malta