Ring prop
Posted: Mon Aug 01, 2005 4:02 pm
Has anyone tried this Ringprop? They dont have them for the Suzuki yet. Looks like just what we should use here in Florida. (Manatees) www.ringprop.com
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Ring prop
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Posted: Mon Aug 01, 2005 4:42 pm
Some discussion here
Posted: Mon Aug 01, 2005 8:24 pm
OK,
The only size the RingProp manufacturer makes (or made at the time) for the Mercury outboard is 10.4 inches diameter, and I bought a 10 pitch. Used it for about 6 months, never got full speed or RPM out of it, at least that size and pitch. West Marine took it back at full price LESS 20% restocking charge, and it was expensive to start with. $190.something, so I got a $160 credit - pretty damn good of them, I think. 'Course i am a preferred customer or whatever they call it.
I really like the design and idea of the RingProp, but it didn't perform on speed. The manufacturer's U.S. tech guy I talked to said not to expect as much top end speed as with a same pitch conventional prop, maybe a couple of MPH less. The tips of the blades are flattened off by that ring. Well with a true powerboat doing 30~60 MPH, maybe it wouldn't be much of a loss, but every MPH on a Mac counts, so that is where the problem is.
When I asked why they didn't make a prop that approximated the performance off a conventional prop at a given pitch, and rename the actual pitch to compensate, the guy said someone would have to get back to me. That was over a month ago. I don't think their engineers are working on sailboat props, with the special qualities we need, just high speed motorboats' props.
Now trying the 12.25 X 9 pitch Black Max Mercury brand prop, best results so far, but still need to raise the motor up and inch or two on the transom before finally deciding on the best numbers.
The only size the RingProp manufacturer makes (or made at the time) for the Mercury outboard is 10.4 inches diameter, and I bought a 10 pitch. Used it for about 6 months, never got full speed or RPM out of it, at least that size and pitch. West Marine took it back at full price LESS 20% restocking charge, and it was expensive to start with. $190.something, so I got a $160 credit - pretty damn good of them, I think. 'Course i am a preferred customer or whatever they call it.
I really like the design and idea of the RingProp, but it didn't perform on speed. The manufacturer's U.S. tech guy I talked to said not to expect as much top end speed as with a same pitch conventional prop, maybe a couple of MPH less. The tips of the blades are flattened off by that ring. Well with a true powerboat doing 30~60 MPH, maybe it wouldn't be much of a loss, but every MPH on a Mac counts, so that is where the problem is.
When I asked why they didn't make a prop that approximated the performance off a conventional prop at a given pitch, and rename the actual pitch to compensate, the guy said someone would have to get back to me. That was over a month ago. I don't think their engineers are working on sailboat props, with the special qualities we need, just high speed motorboats' props.
Now trying the 12.25 X 9 pitch Black Max Mercury brand prop, best results so far, but still need to raise the motor up and inch or two on the transom before finally deciding on the best numbers.
Posted: Tue Aug 02, 2005 12:53 am
If you need to concern yourself about slicing manatees, you might not care about top speed, right IdleTime?ALX357 wrote: ... I really like the design and idea of the RingProp, but it didn't perform on speed. The manufacturer's U.S. tech guy I talked to said not to expect as much top end speed as with a same pitch conventional prop, maybe a couple of MPH less ... but every MPH on a Mac counts, so that is where the problem is.
Posted: Wed Aug 03, 2005 2:45 pm
When I watched the video on their website it looked like a more controled force of water was produced. I thought this might make maneuvering easier with the motor. I dont really mind losing a mph or 2. We usually dont cruise more than 6 or 7 mph anyways. I like to sail every second I can. That's what's nice about the powertilt and roller furling. I even sail the rivers when possible. Of course, I am dragging my feet about getting home once I am out there. Now ,Jim...that's a different story. He likes to power and not mess with the sails if there isnt much wind. We dont do much watertoy stuff here in Florida...kinda like trolling for gators. 
Posted: Wed Aug 03, 2005 2:58 pm
at low speed, the 10.4x10P RingProp gave real good control, smooth and no propwalk when docking. Max speed on my boat was about 11~12 mph, whereas i am now getting 15~17 with conventional props of larger diameter and same or less pitch. That was too much speed for me to sacrifice. my local prop shop guy also said that the motor has to push the ring thru the water, which resistance is significant, as well as having lost the thrust from the truncated the tips of the blades, and the ring does not provide any thrust itself.
....besides being safer for animals, fish and humans, the prop seems more resistant to damage from debris etc. in the water, but consider that it also would be unrepairable if it ever does get damaged, and is almost 2x the cost of a conventional 3-blade prop.
if they made a larger diameter prop for my Merc, or i had an engine that would take a larger available RingProp, i might try it again.
....besides being safer for animals, fish and humans, the prop seems more resistant to damage from debris etc. in the water, but consider that it also would be unrepairable if it ever does get damaged, and is almost 2x the cost of a conventional 3-blade prop.
if they made a larger diameter prop for my Merc, or i had an engine that would take a larger available RingProp, i might try it again.
Posted: Wed Aug 03, 2005 2:59 pm
I share Chip Hindes' philosophy that if it was better for performance, all the manufacturers would probably be doing it.
While it might be better than a bare blade tip, I don't think I'd count on a rotating ring not to cut a manatee. If that's your objective, a stationary prop guard may be better. Florida's FWC Commission has a list of some.
More info...
While it might be better than a bare blade tip, I don't think I'd count on a rotating ring not to cut a manatee. If that's your objective, a stationary prop guard may be better. Florida's FWC Commission has a list of some.
More info...