Folding propellers

[markhomer]

Hi

Ive just bought a new boat to me , an elan 434 with volvo d2 55 with a fixed prop on volvo saildrive , the prop has to go , on my previous boat ( for sale ,bavaria 38 2003 ) I had a volvo folding prop which eventually wore out and i replaced with same , blades one year ,hub etc next , it had lasted over 13 years which i hear is pretty good for a folding prop despite the anode problems .

I have read the folding feathering prop test that ybw carried out , but unfortunately they didnt test the volvo prop .

Looking at the test im leaning towards a flexofold , i want minimum drag under sail , max power under power .

Unfortunately they didnt test the volvo prop , my experience of it over last 7 years has been that it is an excellent prop , with great power and stopping astern performance too , but i cannot judge it against the flexofold as i have no experience of it , im guessing too that volvo is cheaper option and at 13 plus years service and good performance a good option .

In short if volvo as good as flexfold its down to loot . . Flexfold in my eyes in that test is best performer for my needs .

I cruise every weekend and every holiday , im a racer on other boats too hence i cant live with any drag , cruising being what it is we end up motoring a fair bit , shock horror

 

[savageseadog]

Flexofold are the best in terms of performance and resistance to corrosion

 

[AntarcticPilot]

I've got a Gori two-blade floding prop on my Moody 31 with a Volvo 2003 engine. I think it was fairly new when I got her in 2007, and there's no sign of wear or any problems so far! I have taken it apart a couple of times, but there's no visible wear on the teeth that keep the two blade folding out uniformly. Only problem has been that if there's a bit of fouling in the mechanism, it can be a bit sluggish opening in reverse. That isn't a problem as long as its kept reasonably clean.

 

[Skylark]

My 41ft boat came with Yanmar saildrive with very lightweight, aluminium 3-blade, fixed prop. I very quickly changed this for a flex-o-fold.

I remove it every year, at time of haul-out, for cleaning and inspection. After 5 seasons it remains in perfect condition. As I refit it each Spring time I’m always impressed by the engineering. It’s a well made piece of kit and assembles beautifully.

Performance in ahead and astern is very good.

The 2 down-sides, both more personal perception than anything else, are (1) eye wateringly expensive, (2) with its weight, it must be putting signifantly more load on the gear leg/output shaft compared to the original fitment.

Like you, before buying I read all of the available test reports and I now think that the flex-o-fold warrants its good reputation.

 

[Tranona]

Another vote for FlexOfold for all the reasons given so far

 

[dunedin]

We have a Flexofold with a D2-55. Works well

 

[richardbrennan]

I too have had a good experience with a Volvo folding prop. I must have had it for about 15 years now, first with a Volvo 2030 and more recently with a D1-30. It is showing little signs of wear although I do strip it down completely and give it a thorough clean every year. My one winge is that, on my mooring at least, the anodes do not last a year. However, as I come out after six months for a scrub on the Sealift at Haslar, it's no big deal to change them, it just costs a few bob!

 

[Lucky Duck]

Volvo folding props are well known for eating anodes before the end of the season!

I will be interested to see how my new flex-o-fold composite hub with similarly new blades has fared when the boat is lifted out in March compared with the 'mixed' results I have had with their more traditional set up.

 

[DJE]

Fitted a Darglow Featherstream on our Volvo saildrive leg a few years ago. It's been fine and the and the astern power is astonishing.

 

[Skylark]

I will be interested to see how my new flex-o-fold composite hub with similarly new blades has fared when the boat is lifted out in March compared with the 'mixed' results I have had with their more traditional set up.

My first season with a flex-o-fold, I did nothing but fit it and, subjectively, a fair amount of the nose anode had eroded after my 6-month season. In subsequent years, I’ve applied Primocon + Trilux 33 to the prop and its huge boss. I’ve done this as much to reduce the surface area of bare metal in the electrolyte (sea water) as to keep growth at bay. Subjectively again, it seems to be of dual benefit. Maybe worth a try?

 

[jamie N]

Featherstream supplied a 'slightly' custom prop for my Folkboat, which has exceeded expectations, and shows no sign of wear after a season. They had to engineer a slightly different taper for my shaft, and did this perfectly and without fuss. If I were to get another boat, I'd have no hesitation in going to them again.

 

[Lucky Duck]

My first season with a flex-o-fold, I did nothing but fit it and, subjectively, a fair amount of the nose anode had eroded after my 6-month season. In subsequent years, I’ve applied Primocon + Trilux 33 to the prop and its huge boss. I’ve done this as much to reduce the surface area of bare metal in the electrolyte (sea water) as to keep growth at bay. Subjectively again, it seems to be of dual benefit. Maybe worth a try?

I did ask about whether the composite hub should be painted but was advised to leave it as and take it from there.

The anodes are on each of the blades rather than on the hub, fortunately I kind member of the forum sent me a set for next season :encouragement:

 

[Quandary]

I had a D1 30 with a VP three blade folder, great power conversion and performance especially in getting everything out of an overpowered engine for a 33' boat, only downside was the rapid degrading of the little segmental anodes, not just their high cost but the need to lift every winter. (I am not a diver). My current boat is 31 ft and came with a VP 2 blade folder and struggled against adverse wind and sea, last winter I changed it for a Flexofold 3 blade taking advantage of Darglows winter discount, I still had little change from £2k, I get about half a knot more speed( perhaps a knot when the going gets tough) and with a bigger aluminium anode could stay afloat for two seasons, but it probably was an extravagant purchase. But as we get older we motor to windward more and more so I do not regret the purchase though it might have paid for a very nice sail.

 

[yotter]

My 2005 Dufour 34 came with MD2030 saildrive and a Kiwi prop. I am very pleased with the performance. I believe that one of the great advantage (especially with an alloy VP saildrive) is its composite and stainless steel composition meaning that the anode easily lasts 2 seasons. The prop was fitted in 2009 by the previous owner and is still good condition. Worth a thought? And they may be <£1k
Angus

 

[Tranona]

My 2005 Dufour 34 came with MD2030 saildrive and a Kiwi prop. I am very pleased with the performance. I believe that one of the great advantage (especially with an alloy VP saildrive) is its composite and stainless steel composition meaning that the anode easily lasts 2 seasons. The prop was fitted in 2009 by the previous owner and is still good condition. Worth a thought? And they may be <£1k
Angus

The propeller is electrically isolated from the saildrive itself and has no effect on the anode wear rate - positive or negative.

You are right however that the Kiwi does not need its own anode as it has no dissimilar metals.

 

[markhomer]

All good stuff , many thanks , however im committed to a folder rather than featherer as they are less drag , all manufacturers state this .
If anyone has gone from a volvo 3 blade folder to a flexofold 3 blade folder or vice versa , the comparison would be most interesting .

Im not worried about the anode depletion on the volvo , i lift every winter and i know the props last 13 years , which all manufacturers have said thats about as good as it gets , unfortunately there are no direct tests done between these two that i can find , thanks to all for your input .

Cheers

 

[BelleSerene]

My 2005 Dufour 34 came with MD2030 saildrive and a Kiwi prop. I am very pleased with the performance. I believe that one of the great advantage (especially with an alloy VP saildrive) is its composite and stainless steel composition meaning that the anode easily lasts 2 seasons. The prop was fitted in 2009 by the previous owner and is still good condition. Worth a thought? And they may be <£1k
Angus

Yes, the price/ performance of Kiwiprop was amazing and I was similarly pleased with mine. Until one blade fell off it up a river: that didn't please me so much. The evidence is that it hit an underwater obstruction and sheared; but two remaining blades at 120º don't work so well and vibrate horribly.

Fitted a Darglow Featherstream on our Volvo saildrive leg a few years ago. It's been fine and the and the astern power is astonishing.

That was my solution (mine on a Yanmar shaft drive). I found the same. about astern power - although I suspect this applies to all models of feathering props (likely not folding props so much, as their foil is working backwards whereas feathering props swing round to the other attitude when operated in reverse - am I right here?)

But I suspect there's a lot of people (like me) just being happy with whatever they have - few of us have compared different models. (Except where one breaks!)

 

[Tranona]

i know the props last 13 years , which all manufacturers have said thats about as good as it gets , unfortunately there are no direct tests done between these two that i can find , thanks to all for your input .

I would be very disappointed if my FlexoFold lasted only 13 years (7 seasons old now). No reason why it should not last at least as long as a fixed blade prop. Appreciate that it has moving parts, and the 3 blade has far more than my 2 blade, but wear is related to use rather than just age, and if dealt with before it gets bad is not difficult to refurbish. It is wear that is a weakness on the Volvo branded prop in addition to short anode life - and of course the two are often connected.

Volvo have, as far as I know never submitted their propellers to independent tests so you are buying a bit blind based on past experience either your own or from others. Not that the tests so far conducted are particularly definitive in terms of predicting how well they will perform on a particular boat, nor have there been any rigorous assessment of drag when folded/feathered. I am not convinced that a folded Volvo 3 blade has any less drag on a saildrive than a feathered Featherstream for example. About the only thing you can say for sure is that any of the non fixed blade designs are lower drag than a fixed prop of the same size.

 

[Quandary]

Having owned both a Volvo and now a Flexofold I am pretty convinced that the Volvo has less drag when folded but whether that would be sufficient to be quantified is a moot point. Interestingly, there is another Moody S31 sitting next to mine in the club yard this year with the VP three blade so I do not have to go far to make a comparison.
I chose the Flexofold in the hope that I could reduce lift out to every second season, both were available at a discount with which the VP was about 80% of the Flexy, however the advice and support from Darglow regarding sizing options etc was worth the difference.

 

[Malo37]

I've had two Flexofold props on two 40 ft boats. Excellent if a tad expensive. Good technical support from the manufacturer who will advise on sizes.