My last boat had a two blade martec folder that had no vibration. The gori replaced a 3 blade max-prop, that needed a rebuild.
I had similar vibration bands, but it did smooth out around 3000 rpm (yanmar 3gm30f). I know other people swear by them but, I am gun shy. I think I will have AB rebalance it (hopefully at their cost), then sell it on ebay. I just don't think it is right for the boat. Eric On Tue, Feb 12, 2013 at 6:18 PM, Bill Coleman <colt...@verizon.net> wrote: > I think it is partly the rectangular shape, and somewhat the > not-so-aerodynamic curves on those, if I remember right, and I think a big > part is having blade hitting the disturbed water behind the strut. If you > have half your prop smacking disturbed water, vs. a three blade where it is > split up, it is more of a shock every revolution. It seems to affect some > boats more than others. . That is the reason I went to the 3 blade Gori. > **** > > If I wasn’t racing I would have done the 3 blade FlexOFold. I might still. > **** > > ** ** > > ** ** > > Bill Coleman**** > > C&C 39 [image: animated_favicon1]**** > > ** ** > > *From:* CnC-List [mailto:cnc-list-boun...@cnc-list.com] *On Behalf Of *Chris > Tassone > *Sent:* Tuesday, February 12, 2013 5:33 PM > *To:* cnc-list@cnc-list.com > > *Subject:* Re: Stus-List tip clearance**** > > ** ** > > Hi Eric,**** > > When I broke a blade on my 2-blade fixed prop, I bought a Gori 2-blade > 16.5x11 RH for My 1979 C&C 34. I bought a new shaft, coupling and cutlass > to complement the Gori. From 3 to 5 knots I get a lot of noise/vibration. > At 6 knots it is better but still noticeable. After haulout I spoke with > Geoff at AB and they finally agreed to rebalance it. I put it back on an > there was no improvement. I saw Steve from AB at the Strictly Sail Chicago > show last month and he questioned my tip clearance. I measured it at 5" > from the hull. Steve's response was to have it rebalanced again. At this > point I can't live with this prop and am considering going back to a fixed > blade. I spoke to the people at Flexo-Fold and they believe the problem is > the rectangular shape of the Gori blades. They could be right but I'm a > little gun shy regarding folding props.**** > > Chris**** > > ----- Original Message ----- **** > > *From:* Eric Baumes <eric.bau...@gmail.com> **** > > *To:* cnc-list@cnc-list.com **** > > *Sent:* Monday, February 11, 2013 9:25 PM**** > > *Subject:* Re: Stus-List tip clearance**** > > ** ** > > Chris, **** > > ** ** > > What model do you have?**** > > ** ** > > I just yanked my Gori 2-blade prop off my 34/36. I put it on last year and > when it first went on the boat shook like crazy. I got 100 yards out of the > marina, throttled up then turned around. The yard hauled the boat, check > the shaft for true, put it back in the water, aligned the engine, drove it, > aligned the engine again. **** > > ** ** > > I picked the boat up as the racing season had started, and took the boat 9 > hours to a regatta. On the way home I brought it back to the boat yard as > the vibration was still bad except for a few RPM bands. I talked with AB > marine and they didn't have a 1 1/8' hub but swapped out the blades. The > boat came out of the water, blades swapped and went back in. It was better, > but when I took the boat out on a cruise, I found the vibration/noise and > the complaint of my wife who sleeps in the aft cabin when I leave anchorage > early that it was much louder than last year.**** > > ** ** > > As I said, I had the yard pull the prop and I am going to contact AB > Marine this week. Given everything I went through last year, I am really > tempted to just get a martec. If they tell me the prop is fine, then I > don't want to put it back on the boat. If they tell me it had to be > balanced, I am not sure I trust putting it back on the boat.**** > > ** ** > > Eric **** > > 34/36 #74**** > > On Fri, Feb 8, 2013 at 7:55 PM, Chris Tassone <ctass...@charter.net> > wrote:**** > > Steve,**** > > Thanks for getting back to me. I doubt getting this Gori 2-blade 16.5 x > 11 RH prop rebalanced will help since I already did this and the results > we're negative. After trying to resolve this for the last three years I > think the only solution is a new prop. I relied on your company's > expertise to size this prop for me and I made a mistake that I will have to > live with. If you know of anyone that wants to buy a prop please let me > know. Thanks for your concern.**** > > Chris**** > > ----- Original Message ----- **** > > *From:* Steve Armitage <st...@ab-marine.com> **** > > *To:* Chris Tassone <ctass...@charter.net> **** > > *Sent:* Friday, February 08, 2013 12:22 PM**** > > *Subject:* Re: tip clearance**** > > ** ** > > Dear Sir, **** > > ** ** > > Perhaps the thing to do is have the propeller removed and re-balanced as i > think you have enough tip clearance and don't see this as an issue. Sorry > that i cannot be more helpful than that. > **** > > Regards, Steve Armitage **** > > AB Marine, Inc**** > > 747 Aquidneck Ave**** > > Middletown, RI 02842**** > > sa...@ab-marine.com**** > > 401-847-7960**** > > ** ** > > On Sat, Feb 2, 2013 at 4:58 PM, Chris Tassone <ctass...@charter.net> > wrote:**** > > Hi Steve,**** > > My name is Chris Tassone. I spoke with you at Strictly Sail Chicago > concerning the noise I get with my Gori 16.5" x 11 x 2rh prop. You > suggested that tip clearance could be the culprit. My tip clearance is > 5-1/2". I spread the prop by spanning the blades and hub with a strait > edge and measured this distance. I also measured the distance on my 1" > shaft from the cutlass to the front of the prop hub which is 1-3/8". My > boat is a 1979 C&C 34 with a Yanmar 2QM. The noise is really noticeable > and could be a concern if I ever try to sell the boat. Would a smaller > prop solve the problem? I installed a new shaft and coupling when I > purchased the Gori. I lapped the shaft and checked it with a dial > indicator. The shaft is aligned. I really appreciate your attention.**** > > Thanks,**** > > Chris Tassone**** > > 231-946-8185 H**** > > 231-883-1234 C**** > > ** ** > > > _______________________________________________ > This List is provided by the C&C Photo Album > http://www.cncphotoalbum.com > CnC-List@cnc-list.com**** > > ** ** > ------------------------------ > > _______________________________________________ > This List is provided by the C&C Photo Album > http://www.cncphotoalbum.com > CnC-List@cnc-list.com**** > > > _______________________________________________ > This List is provided by the C&C Photo Album > http://www.cncphotoalbum.com > CnC-List@cnc-list.com > >
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