Folding Props

[Sailfree]

After 6 yrs of charter use my feathering prop is off to Germany for a full service next lift out. Now as a charter boat it is only out for the minimum period of time. I may have to temporarily fit a replacement prop. Boat is 43' with 75HP Yanmar shaft drive.

You can ask SWMBO what happened to the original fixed prop when she decided to clear up the garage as if I did it might drive me to violence!!

As I understand it there are only about 3 or 4 main makes of Folding props but price can vary by 100%. Flex of Fold, Varifold & Volvo Folding {are the latter still made by Redice(spelling?)} Any others?

To save re-inventing the wheel can anyone advise me of the main differences and reasons for your choice if relevant.

Basically being a charter boat it must be idiot proof and predictable as otherwise any cock -ups in berthing is the boat/props fault so Bruntons self pitch and Gori with overdrive are out. Of the remaining the one that performs best going astern as a crash stop could save me 12" of my bow section!!

Thanks

 

[earlybird]

I have owned 2 boats with Radice and 1 boat with Flexofold. All 2 bladers. The Flexofold seems to have slightly better forward and astern drive, and also opens more readily in astern. It also seems less prone to vibration in astern, it would be my choice from those makes.
No mechanical trouble from either make.
Neither gives brilliant stopping power however.

 

[kengill]

Varifold folding props

I'm happy with mine. They are simple, robust and just require a self-adhesive rubber bumper replacing every so often.

The tests done last year by yachting monthly showed them to be the best overall with a moderate kick in reverse ,rather than none, to aid reversing out from a berth in a crowded marina.

cheers
Ken

 

[Stork_III]

As your having your expensive feathering prop refurbished, fit a fixed three blade in the interim, cheap with good reverse.

 

[Dockhead]

Basically being a charter boat it must be idiot proof and predictable as otherwise any cock -ups in berthing is the boat/props fault so Bruntons self pitch and Gori with overdrive are out. Of the remaining the one that performs best going astern as a crash stop could save me 12" of my bow section!!

Thanks

I believe the Bruton Autoprop has the best of all drive in astern, and I think it's fairly idiot-proof. It does an excellent crash stop and has very strong drive in astern -- basically identical to the drive in ahead. It doesn't have any gears since the angle of the blades is set by a balance of centrifugal and hydrodynamic force, so they are simpler than others -- less mechanism to service and less to break.

It has the poorest of all sailing performance, compared to other folding/feathering props, because of this same lack of gears -- one blade is always drooping down and causing resistance. But all other aspects are brilliant. The self-pitching feature, which I think is unique, is fantastic for motor-sailing. They have very little prop walk.

We like ours and can recommend.

 

[YELLOW BOAT]

Yes Volvo is made by Radice ( or better Eliche Radice) . They only polish them to a high gloss which is not the case when you buy a Radice directly.
However Radice props sold as Radice are not identical to Volvo of course.
Ad

 

[Sans Bateau]

Sorry Dockhead, but I have in front of me the YM test and the Bruton Autoprop 3B was, in reverse on the bollard pull, around 2/3 the way down the table, slightly worse than the Flexofold 2B. But the Autoprop did fare better in the stopping time, about halfway down the table, 2 secs better than the worst and 2 secs behind the best. If that makes sense.

But as has been suggested, why not a fixed prop for a short time?

 

[Sailfree]

But as has been suggested, why not a fixed prop for a short time?

With the cost of extra lift out, if it is to be used only for a short time, and the tears I will shed buying again what SWMBO decided to take to the tip (and you want to see the back of my nearly new estate that has been used as a garbage truck) I think I will be tempted to investigate the cost of divorce - probably better to buy a folding prop for 1 yrs use!!


Oh yes and Yanmar gearbox locks up if you use reverse to lock shaft and the consequental whine really hurts my engineering mind let alone the extra wear onthe gearbox and cutless bearings!!

 

[Sans Bateau]

That makes sense, not the domestic bit, you'll have to sort that out!!

The flexofold is what I have just bought, no such thing as a 'best' prop, but in my opinion its the best compromise, for me. Decent, but not best, reverse thrust, but top performance forward thrust.

 

[scottie]

Try a kiwi if it will take the power

 

[Sans Bateau]

Try a kiwi if it will take the power

Mmm, why?

In the YM test, it had the worst max speed, .65knt slower than a Flexofold and worst bollard pull bar one. OK the reverse bollard pull was middle order, but stopping time was again not as good as the Flexofold.

Oh, and it was more expensive, a no brainer me think.

 

[scottie]

Kiwi because it's a reasonably priced feathering prop that works well and is not subject to blades falling off or drooping or corrosion and simply does what it says on the tin
We have used one for 5 years and appears to be as new

 

[pelissima]

Kiwi prop

Another vote for Kiwi.

And by the way, if your shaft is 30mm, I am considering selling mine for 550 GBP, used for two seasons on a First 38 and in as new condition.

 

[Pinnacle]

Another vote for Kiwi.

And by the way, if your shaft is 30mm, I am considering selling mine for 550 GBP, used for two seasons on a First 38 and in as new condition.

So, you love it and yet you are selling it.......hmmm...

Have you sold the boat with the original fixed bladed prop????

 

[vyv_cox]

Oh yes and Yanmar gearbox locks up if you use reverse to lock shaft and the consequental whine really hurts my engineering mind let alone the extra wear onthe gearbox and cutless bearings!!

Yanmar gearbox in reverse does lock the gearchange but as has been posted several times, Yanmar recommend that you either start the engine in reverse, which is what I have done for years, or blip the starter with the decompression out to take it out of gear.

 

[Theshipscat]

The test was inadequate. Not to say it was YMs fault though. A true comparison test is impossible.
I was looking for a three blade folder at the time (I had a three blade fixed). I must have read that test 100 times. The fact was that the differences in performance was minimal between all the three bladers and the props would behave differently on any other boat made it a bit of a lottery.
After speaking to Darglow at the boat show I really wanted the flexifold but thanks to the rise in the euro it went up in price by £300 a month later. While at the boat show Steel developments offered me the actual prop used in the YM test. After reading the test again I decided the price and good points outweighed the bad.
It's been on the boat for a season now. Reverse is slow to respond and kicks to port. Forwards is excellent. Very responsive and faster with lower revs. Sailing is quicker by about 1/2 knot.
At the time every one I spoke to in the yachting business (designers, engineers, etc) said don't get a kiwi. Yet when you talk to owners they have nothing but praise.
I think the point is there isn't a perfect prop they're all different to some degree and
different again on each hull.
If you're happy with your prop and you really have to have another three blade folder why not just by another the same?

 

[pelissima]

Kiwi feathering prop

So, you love it and yet you are selling it.......hmmm...

Have you sold the boat with the original fixed bladed prop????

No, I simply returned to my fixed two bladed.
When racing I was never able to do better than my penalty.

 

[Silver Cloud]

Problems with Autoprop service

I have an Autoprop. AB Marine had rebuilt the prop in 2007. In May of 2009 and 225 hours later a blade came off. Buntons Marine replaced the blade for $1500. I had it lubricated every six months. I am always in deep water. It never touched anything but saltwater. I only go to Catalina and back. Other than the lost blade there was not any evidence of damage or distress.

At the time Steve Armitage of AB Marine told me that losing a blade was a “rare occurrence” and that he did not have an explanation for why the blade fell off. David Sheppard of Brunton's Propellers Ltd, told me losing a blade is an “an exceptional case”. Contrary to their comments the prop has been subject to a recall for lost blades. If you search other support groups and blogs you will find many others that have lost Autoprop blades. It demeans their credibility to say otherwise.

Although I enjoy the performance of my Autoprop my experience with AB Marine and Brunton's Propellers has been extremely disappointing. They are unwilling to stand behind their expensive product. In all their replies I feel like I am hearing from a politician trying to avoid giving a straight answer.

 

[Sailfree]

I have an Autoprop. AB Marine had rebuilt the prop in 2007. In May of 2009 and 225 hours later a blade came off. Buntons Marine replaced the blade for $1500. I had it lubricated every six months.

Sorry to hear of your troubles. I investigated props thoroughly after the Volvo folding prop on my 1st boat failed 3 times.

I recently wrote this to someone else but its appropriate here.

I did consider the Kiwi but choose not to go for the Kiwi prop as the blades will get damaged if you get a rope wrap where the phosphor bronze blades would not and the reverse is a set (non- adjustable) pitch and overgeared and I have read of problems regarding this.

Although exceptional, one of my very first seasons sailing in my Dufour 36 (30HP) I got one very thick fishing net wrap, one lobster pot, 2 ropes and one water skiing handle and its tow rope around the prop and that stopped the Volvo folding prop from operating. I have always used an ambassador rope cutter with any prop after that season!! I also wondered about the internals/strength and wear if Kiwi are limited to a certain power (I see from recent posts its 50HP). My current 4 blade variprop (75HP) has now done some 1500 hours and no blade damage at all.

I considered the Darglow feathering prop but found that for charter use they recommended a more expensive bigger hub. I liked the IIRC "Seastream" which is all SS but expensive. For my 2nd boat (Dufour38) I finally chose a Variprop feathering prop as the best. I liked the solid German engineering and the internal cushion effect when it changes direction. Unfortunately on this boat I only had it on for a short while until the bl@@dy Volvo gearbox went (occassionally would not go forwards from astern) Volvo insisted it was the prop so I sent it back with a complaint. One lift out later and a new folding prop and the same problem Volvo finally accepted there must be something wrong with the gearbox (yet another of the many Volvo failures!!). Sold the boat with a new Volvo gearbox/saildrive and the folding prop hence I have a lightly used Variprop suitable for a 40HP Yanmar/Volvo saildrive, fully serviced and returned with an apologetic note "Sorry we could find nothing wrong with your Variprop!"

For 3rd boat stuck with Variprop and now done some 1500hrs with no probs but must turn round winter lift out quickly as boat goes out on charter hence considering a folding prop for 4 months until boat comes out again for a scrub. Obviously in my case one charter pays for the new extra prop!!

PS As I have mentioned before - After I sold the boat the new Volvo gearbox on the Dufour 38 did not last long as the whole saildrive leg sheared off outside Cherbourg. Luckily my spec for my 3rd boat was no bits on it that start with "V" and Yanmar has so far been trouble free.