brians
Member
Got a VP2020 which needs a new propeller. Have been offered choice of 2 or 3 blades or folding. Is there any benefit of 2 over 3 blades?
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2 or 3 blade propeller
- Thread starter brians
- Start date
Talbot
Active member
If you need a new propellor, then make sure you buy a decent folding one suited to that engine/boat combo. This will make a bigger difference to your overall sailing, than buying a cruising chute!!!!
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alec
New member
Wise words Talbot !
I bought a spinnaker last season and used it once in 47 days of sailing. I think they can be enormous fun but all I have done is move the thing around the boat a few dozen times. Even when the wind is light and ideal, as we know, the wind tends to get flukey and decides to box the compass every few minutes. If a sailor has plenty of crew who like to play when the wind is light then they come into their own. But I say, leave them to the racer's !
I would say overall, you will get more pleasure spending money on a nice posh folding prop ( as you will get more sailing done v motoring over a season ) or splash out and buy a lovely new sail.
If anybody would like to present me with a 13" folding prop they can have my spinnaker plus a nice petrol lawnmower that I don't seem to use anymore.
Best of luck and spend the money ! (It's later than you think).
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I bought a spinnaker last season and used it once in 47 days of sailing. I think they can be enormous fun but all I have done is move the thing around the boat a few dozen times. Even when the wind is light and ideal, as we know, the wind tends to get flukey and decides to box the compass every few minutes. If a sailor has plenty of crew who like to play when the wind is light then they come into their own. But I say, leave them to the racer's !
I would say overall, you will get more pleasure spending money on a nice posh folding prop ( as you will get more sailing done v motoring over a season ) or splash out and buy a lovely new sail.
If anybody would like to present me with a 13" folding prop they can have my spinnaker plus a nice petrol lawnmower that I don't seem to use anymore.
Best of luck and spend the money ! (It's later than you think).
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Chris_Stannard
New member
IMHO there is no advantage to a two bladed prop except that it is cheaper. A well designed three balded unit will give you better performance all round. I have a three bladed Flex-o-fold but I consulted the engine makers for advice before I decided on what the right size for my boat/engine comination would be.
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KipH
New member
3 blade is more efficient, 2 blade offers less drag. In the Pardeys' books I've read a folding prop added 8-12% to the daily run in light winds, as compared to a fixed 3 blade, and a fixed 2 blade was also close to 10% less.
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ashanta
New member
I have just bought a volvo 3 blade folding prop after considerable research. See the threads on this.
I have just received the prop and was suprised at the weight in comparison to my fixed 2 blade ali prop.
I have just had some feedback from others who have also converted to the 3 blade folding and they say there is no problem with the additional weight.
The 3 blade folding prop is as good as the 2 blade folding. They are no different in sailing performance. The 3 blade folding prop is superior to the 2 blade folding when motoring, especially in reverse.
I hope this info helps?
Regards.
Peter.
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I have just received the prop and was suprised at the weight in comparison to my fixed 2 blade ali prop.
I have just had some feedback from others who have also converted to the 3 blade folding and they say there is no problem with the additional weight.
The 3 blade folding prop is as good as the 2 blade folding. They are no different in sailing performance. The 3 blade folding prop is superior to the 2 blade folding when motoring, especially in reverse.
I hope this info helps?
Regards.
Peter.
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sailorman
Well-known member
go folding, why tow a bucket ?.
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PeterGibbs
New member
The closer you get to a complete disc the more thrust - 3 blades therefore more thrust than most 2 blades. Some will assert the more disc the more drag; this is not true, especially if you let the prop rotate when sailing (just wait for the howls of disbelief at this assertion!)
Do you value being able to really get some rush going when you need it to get home / to shelter? Does you boat have high windage? - 3 blades is for you.
Do you fuss that you cannot sail at 10 knots on a windless day and blame your fixed prop? A folding blade is for you (notwithstanding that carrying the usual tonne of spares and food/water/fuel will always do more to wreck your performance than any fixed prop!)
As you observe, there is psychology at work at work here in answering your question, but the dynamics do have some part to play.
I sail a 38 foot 9 tonne boat and have a 3 bladed fixed prop. When I stop the prop
from freewheeling, I see the wake churn up some when sailing. Boat speed is not affected. With a smaller boat it might have some effect. But then I am not racing and counting every split second. Nothing would persuade me to fit a folding prop - even if I won it in a raffle! And I would never go back to 2 blades - useless in any kind of seaway!
PWG
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Do you value being able to really get some rush going when you need it to get home / to shelter? Does you boat have high windage? - 3 blades is for you.
Do you fuss that you cannot sail at 10 knots on a windless day and blame your fixed prop? A folding blade is for you (notwithstanding that carrying the usual tonne of spares and food/water/fuel will always do more to wreck your performance than any fixed prop!)
As you observe, there is psychology at work at work here in answering your question, but the dynamics do have some part to play.
I sail a 38 foot 9 tonne boat and have a 3 bladed fixed prop. When I stop the prop
from freewheeling, I see the wake churn up some when sailing. Boat speed is not affected. With a smaller boat it might have some effect. But then I am not racing and counting every split second. Nothing would persuade me to fit a folding prop - even if I won it in a raffle! And I would never go back to 2 blades - useless in any kind of seaway!
PWG
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brianhumber
New member
Replaced my under pitched 2 blade folding with correctly sized GORI 3 blade folding some 7 years ago. Greatly improved manouvering, uses less revs and gives better fuel consumption for normal motoring. Well worth the pennies if you are going to be keeping your vessel for some years.
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brians
Member
Thanks to everyone for all the advice.
I have since seen a graph on the last page of the Volvo Penta 2003 Parts Guide which compares the drag effect of 5 types of propeller which bears out the advice. Now have to decide whether to spend the £300 on this or a Navtex. As it is Xmas perhaps both?
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I have since seen a graph on the last page of the Volvo Penta 2003 Parts Guide which compares the drag effect of 5 types of propeller which bears out the advice. Now have to decide whether to spend the £300 on this or a Navtex. As it is Xmas perhaps both?
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ashanta
New member
Volvo 2 blade folding = £550
Volvo 3 blade folding = £850
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Volvo 3 blade folding = £850
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brians
Member
The £300 was actually meant to mean 'extra over' fixed.
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Aeolus_IV
New member
I would suggest that you only get what you pay for. We changed our fixed 2 bladed prop for a Gori folding 2 blade prop, and seem to have found a win-win situation. The boat is faster under power, much faster under sail and while astern isn't positive I don't feel it is any less managable than with the old fixed prop. I would have prefered the 3 bladed version, but it had already been an expensive year so we settled for the best folding prop we could afford. The best single change we have made to the boat since getting her.
Regards, Jeff.
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Regards, Jeff.
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sailorman
Well-known member
Kurrawong Kid also has a Centurion 32 & has just re-engined with the Beta 29 + Gori prop.
perhaps we can encourage him to tell of his experence
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perhaps we can encourage him to tell of his experence
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Aeolus_IV
New member
Yes - would be interesting to know what he has fitted. I am feeling that in retrospect the 3GM we fitted is probably too powerful given the (enforced) small size of the prop. But as this engine is significantly lighter than the MD2B we took out its not that important, just that I'm not convinced that even flat out we are placing a heavy load on the engine. The good point seems to be that even though the 15"x12" prop is really too small for the engine it seems to be handling the power very well (quality showing though - the original 15"x12" fixed prop wasn't 1/2 so good). Time will tell when we need to motor into some serious weather.
Jeff.
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Jeff.
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brians
Member
Are Gori and VP folding props much the same? For warranty reasons think I am stuck with VP anyway.
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Aeolus_IV
New member
Depends on which propeller you are looking at. Gori can be found <A target="_blank" HREF=http://www.gori-propeller.dk>here</A>. You'll know which VP propeller you have, so you can make your own comparisons. The three bladed Gori is the really unique one, the blades fold at 90 degrees to the traditional folding propeller. The two blade is a traditional design - but just seems to work exceptionally well (we have the oridinary one rather than the racing one).
Regards, Jeff.
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Regards, Jeff.
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Apetts
New member
How does the volvo prop compare with a fixed three blade?
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