Best prop for First 32S5?

[miamibeachboatbums]

Hey all,
I need a new prop and the 3 bladed prop I had was not right for the boat (only 3-4 kts). Does anyone have any suggestions on a good folding or none folding prop to go with?
My 32S5 has a Yanmar G2M 18HP. What pitch has everyone found to be the best for bit and speed? Do you suggest folding or fixed and what pitches have been the best for you?

Thanks so much for the feedback.
Danny Martin,

 

[JohnShannon]

Why are you sure it is the prop?

 

[miamibeachboatbums]

Because I know the prop is not original from the boat. Performance wise it gives us maybe 4-5 knots and has poor bit. Boat is on the dry, motor and transmission have been pulled and were in, and are in, great shape. I'm looking for historical data on what has been a good working prop on the 32S5. How many blades, what pitch, folding or fixed if anyone can help. Thanks Danny

 

[DDF]

Hi Danny, we had a Gori 2-blade folding on our 32s5, no problem to reach 6kn in the mostly calm sea of Stockholm archipelago.
Its marked "16 1/2 x 11 LH".

But it gave poor "grip" especially when reversing, making it tough to manoeuver, and also on rougher sea.
So new for this year is a shiny flexofold 3-blades folding, just installed the beauty but boat is on land still. Going afloat next week, will share the experience.
We have a VP2002 engine, 18hp, not sure if your yanmar is LH or RH.
Cheers
David

 

[miamibeachboatbums]

David, thank you for your feedback. I would be very interested in how it performs after you splash. Thanks so much. Cheers Danny
Mine is RH, three bladed fixed that did not originally come with the boat.

 

[Jackdaw]

Two bladed Flexofold on the First 36.7. Beneteau standard equipment on this (and all other First models) boat. Very good performance, both forward and in reverse.

 

[miamibeachboatbums]

Thanks Jackdaw. I assume if I go to flexofold they would know proper pitch for First 32S5? Thanks

 

[Jackdaw]

Thanks Jackdaw. I assume if I go to flexofold they would know proper pitch for First 32S5? Thanks

Yes indeed. Actually the best way to do it is to call the factory. They will take your boat, motor, and transmission info and spec the prop for you. If they get it wrong they will swap the blades.

 

[DDF]

Would be surprised they have anything on record for the 32s5, otherwise i'm interested to know.
The company i bought the new prop from was running tons of data in a program (waterline length, max rpm, age of the captain etc..). Which certainly results in whatever they want to sell out from stock
Anyway, will let you after the test, which i really look forward to. Just checked the invoice, new prop is a 16 x 10, quite similar to old but 3 blades.

 

[Davidasailor26]

We also just got a Flexofold 3 blade for our Oceanis 37. We used their web form to provide the engine and transmission info and they replied with the size. So far it seems like power in forward is about the same as the OEM fixed 3 blade. Reverse is a little less aggressive but still completely adequate. Obviously under sail it's much better - maybe a quarter knot in moderate winds - still need more data to say exactly.

 

[miamibeachboatbums]

So I got this feedback from Flex o fold in Denmark.
One would choose a 2-blade propeller because, in flat water, it will reach a higher speed for any given RPM. It will also have lower drag under sail and will cost less.

The 3-blade Flexofold will perform better in maneuvers around the docks, in forward and reverse, will attain a higher average speed against a head sea, and will stop the boat quicker. The 3-blade may also be a little smoother running if there is a problem with vibration.

The choice of 2-blade vs. 3 blade is really up to your personal preferences.

Any opinions here? The boat came stock with a 2 blade. I don't plan on racing the boat really, more cruising than anything. There is also not a lot of flat water in Miami, so I'm leaning towards the 3 blade. The 3 blade fixed I had on the boat was really bad, but probably the wrong pitch on it. Any thoughts? Thanks Danny

 

[Jackdaw]

So I got this feedback from Flex o fold in Denmark.
One would choose a 2-blade propeller because, in flat water, it will reach a higher speed for any given RPM. It will also have lower drag under sail and will cost less.

The 3-blade Flexofold will perform better in maneuvers around the docks, in forward and reverse, will attain a higher average speed against a head sea, and will stop the boat quicker. The 3-blade may also be a little smoother running if there is a problem with vibration.

The choice of 2-blade vs. 3 blade is really up to your personal preferences.

Any opinions here? The boat came stock with a 2 blade. I don't plan on racing the boat really, more cruising than anything. There is also not a lot of flat water in Miami, so I'm leaning towards the 3 blade. The 3 blade fixed I had on the boat was really bad, but probably the wrong pitch on it. Any thoughts? Thanks Danny

While most will not intuitively think the first point is true, it 100% is.

 

[DDF]

Pure empiric observation from our pretty crowded and calm waters, any floating object will run 6kn, plus minus 1. So certainly any sort of prop should do ok, in calm waters.
But i remember motoring from protected water (5-6kn speed) into rougher water with our 32s5, and totally stopped for a minute before regaining some speed (3-4kn ish)
One of the reasons for us to go for 3 blades.

 

[Davidasailor26]

When I was looking for reviews of Flexofolds, the only negative reviews I could find were about excessive vibration on 2-blades. I didn't see any reports of similar issues with 3 blades. Not a scientific comparison by any means, but an interesting data point.

 

[DDF]

Hi Danny, so finally our 32s5 went afloat today, with the new prop.
First, as i think you have your boat in Miami: feel happy! We had temperature just above freezing today, and weather half hour sun and no wind, half hour hail-snow and 20kn.. and so on.. 1cm of snow on deck, good start for season 2017!

We tested the flexofold 3 blades 16x10, runs well. 6.4kn at march rpm, thats slightly faster. Not much chance to do complex maneuver, but reverse definitively felt stronger. So:
- Old Gori 2-blades folding 16.5 x11, no problem to reach 6kn in calm water, but poor "grip"
- New flexofold 16x10 3 blades, slighty faster and better grip.
And my wallet is also much lighter

Good luck for the decision and especially if you change the prop. Old ones can sit like stone on the axis!

Cheers
David

 

[miamibeachboatbums]

David,
I can't thank you enough for providing me that feedback. Especially with the freezing temperatures you have up there. How did you come about deciding on the 16x10? You may have a different motor than me? I have a Yanmar 2gm20f, 18hp at 3600 RPM max. But the people at flexofold sent me this information relative to my 32s5 with that motor.

With a 2GM20, max rated 18hp/3600rpm ( gear reduction ratio 1:2,61 ) we would recommend a 2-blade 15x12R or a 3-blade 15x11-3R propeller for your Beneteau First 32s5.
The price for a complete 2-blade 15x12R propeller with hub for ISO standard shaft is USD 1,145
The price for a complete 3-blade 15x11-3R propeller with hub for ISO standard shaft is USD 1,975.

I just want to be sure I'm spending my money on the right size prop. Did they tell you that you needed a 16x10 for the 3 blade?

Thanks Danny Martin

 

[miamibeachboatbums]

Mine is RH spin. Who did all the data calculations for you prop David?
Thanks, Danny

 

[DDF]

A local retailer specialized in props, agent for flexofold. Now that you mention gear reduction, that was one of the key parameters indeed.

So certainly the feedback you got is better suited to your engine (even if a 16×10 would certainly do pretty ok anyway).

Cheers
David

 

[miamibeachboatbums]

Hey David et al, another question for you. So I have been considering getting a fixed 3 blade prop instead of the Flex o Fold 3 bladed prop. Did you ever have a fixed bladed prop on your boat? If so, did you like it? How much speed did you think you lost when under sail? I know the original prop for the boat was a 2 bladed Flex o fold. It makes sense that it would originally have a folding prop for the boats speed characteristics. I don't plan on racing the boat, besides some joyride racing when I'm around friends. I had to re-rig the entire boat from the deck up since it had lost it's mast and rigging in an accident. With that I went with a roller furling system on the Main and Genoa. So I'm already going to lose a little speed from the non-battened main. I'm just wondering how much I would lose by going with a fixed 3 blade prop as opposed to a folding? The cost difference is significant. $700 fixed, $2000 folding. I'm trying to see if it makes any sense? Feedback anyone?

Thanks all for your thoughts.
Danny

 

[Davidasailor26]

Having switched from a 3 blade fixed to 3 blade FOF we wouldn't switch back. Speed under sail is probably about an extra .2 kts in moderate winds; still need a few more days out to really compare. But there are other advantages too. Prop walk in reverse is reduced, making it easier to back out of our slip. Also, under sail with the fixed prop there seemed to be a lot of turbulence in front of the rudder, reducing steering responsiveness in very high and very low winds. So far that seems much improved with the FOF that doesn't make that big turbulent area. Finally, the smoothness when sailing without a freewheeling prop making noise is a really notable change. I know you can lock the fixed prop in reverse to stop the freewheeling but Yanmar recommends against that for their transmissions.