Folding/feathering propeller

We had a 3 blade MaxProp (I think, 21"), came with the boat. Seemed to work well (serviced myself every other year) until killed by an underwater rope in Dieppe. The rope cutter did not help as it broke as well. The internal gears broke, the blades were at different angles and did not rotate anymore. Made for interesting mooring maneuvers....
Fitted a fixed prop (21" x 20", 3 blades) as a quick temporary solution. This spring we went to a Flexofold 3 blades (23" x 19"). I liked the sturdy and simple design, good test report and haggled a good price at the Boot in Düsseldorf.

I initially thought, the MaxProp was good, but now comparing the 3 props on the same boat, would never use a feathering prop again. The Maxprop had a lot more prop walk than the other 2. It did not load the engine enough. I think it was too small. Which is why they set the blade angle to maximum. I think, that made it cavitate.

The fixed prop was a relevation. Powerful push forward and backward (no comparison with the MaxProp), higher speed at same rpm, almost no propwalk (reversing was a dream). Disadvantage was the spinning shaft when sailing. There was no way to stop the prop (we have a hydraulic transmission).

This spring the Flexofold was fitted. Calculated by Flexofold and maximised in size to fit under the boat (47foot, 16tons). Beautiful! What a simple and sturdy design and great performance! In forward almost the same as the fixed one. Reverse of course less efficient because of partly folding blades (as advised by Flexofold) but again, almost no prop walk. Just give it a bit more wellie to compensate.

Bottom line: folding prop every time because of simple and sturdy design, quiet sailing, efficient forward and I hope, lower chance of catching any rope now.

Hope that helps, as I could compare 3 different props at the same boat (at a cost....)

Findus
 
Today fitted a two blade Flex o Fold in place of a Gori. On the advice of others. We will see.
 
I have a feathering Variprop (3 blade) on my 28ft, 4 ton motor sailer. Seems very satisfactory (except expensive anode), though as it's been on the boat since I acquired it I have nothing to directly compare it with.

I was not impressed by Bruntons, who had supplied the prop to the previous owner (for what seemed to me a very tidy sum). While ordering a couple of anodes for it from them, I asked them a simple technical query about the prop (can't remember what it was now), and I was told 'nothing to do us, contact the German manufacturer'.
 
We have a 2-bladed Volvo folding prop, since 2000. Although it is what was recommended, and works well, I might have preferred the 3-bladed version, with a bit more push and working at lower revs. Our current one is absolutely fine in general use, and remains in good condition on its saildrive.
 
I fitted Darglow Featherstream as part of re-engining last year. Therefore hard to apportion performance improvement under power but no complaints. Definite improvement in sailing performance but some of that probably down to cleaner bottom. Darglow customer service excellent. After 9 months prop anode had nearly disappeared so put an extra shaft anode on.

BTW I know you have to put in reverse when sailing to feather but I leave it in reverse rather than going back to neutral as I seem to remember that is advice for TMC gearbox.
 
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I had a Bruntons auto prop which kept on causing engine overheat and quite severe vibration plus we were unable to get full revs as per SD50 manual, cut a long story short Buntons changed the prop to reduce the pitch - same issues occurred so they changed it to a 3 blade folding prop which works well with no issues whatsoever.... so obviously very pleased and we also had an ambassador rope cutter fitted
 
I have had a Volvo three blade folding prop on my boat for about 15 years now, first with a VP 2030 and more recently with a D1-30. Performance is excellent in ahead and astern and it is showing no signs of wear. However, as others have mentioned, it does eat anodes, and I find I have to change them twice a year. Apart from the expense, I don't find this a great problem as I change them once when the boat is ashore for the annual hull polish and antifouling, and again when it has it's six monthly scrub on the Boat Lift at Haslar Marina. They are easy and quick to change.
 
Replaced a 3blade fixed on 40’er with a 19” max prop and loved it. The pitch is adjustable so I over-pitched it slightly for lazy motor-sailing. It was brilliant in astern as well with tremendous grip.
My new boat which has the identical hull, engine and gearbox is fitted with a 3 blade flexofold and i would swap for the max prop in a heartbeat. Compared to max prop you have to rev the nuts off it to get any decent grip in astern.
Another aspect of the flexofold and and really most props is stopping it when transitioning from motoring as you have to stop the prop to make it fold and that clang from the gearbox puts my teeth on edge. The max prop was much gentler on this transition and often would just feather once put into neutral(I think it’s a couple of years ago).

I think the maxprop needs more maintenance.

Either are a massive improvement on the fixed 3 blade.
 
Replaced a fixed 2-blade with a 3-blade Brunton's Varifold on a Moody 31 bilge keeler.
Very happy with it. Great for sailing & motoring forwards. Less pull in astern and less propwalk (but still noticeable).
Pretty happy with Brunton, but the anodes seem to deteriorate rather rapidly.
 
I've only ever had a 3-bladed Brunton's Autoprop, but it seems to be good. Our boat is 12T and about 11m at the waterline with a long fin and skeg. She'll do 8kts under sail and 8kts under engine when really pushing it. When we turn the noisemaker off the propshaft is normally still turning, sticking the gearbox in reverse normally locks it and adds between 0.5 and 1 kt to our speed.
 
I’m taking the plunge on fitting a feathering prop to my 35’ boat of around 6.4t loaded.
It’s certainly a buyer mine field knowing what to go for.

I need people’s experience with their folders and feathering props, with an honest opinion of their pro’s and con’s

Thanks
How have you found your feathering prop? We are undecided between a 3 blade Featherstream and three blade FlexoFold
 
I fitted Darglow Featherstream as part of re-engining last year. Therefore hard to apportion performance improvement under power but no complaints. Definite improvement in sailing performance but some of that probably down to cleaner bottom. Darglow customer service excellent. After 9 months prop anode had nearly disappeared so put an extra shaft anode on.

BTW I know you have to put in reverse when sailing to feather but I leave it in reverse rather than going back to neutral as I seem to remember that is advice for TMC gearbox.
How do you feel about the Featherstream a year later? We are trying to decide between that and the Flexofold
 
I contacted Flexofold. They took details of boat (37') and engine and I followed their suggestion replacing a Gori. Huge difference - rather than at 3000rpm struggling at 6.5kts I was roaring along at 7.5.
 
I did this a couple of years ago. Where I got to with it was:-

If boatspeed under sail AND power is the most important thing to you, get a Fexofold.

If you want the best manouvarability (especially in reverse), then go for a Featherstream.

The Featherstream also has the ability for you to change the pitch, so there's not change of being stuck with a prop that's wrong if you find that it wasn't exactly the right pitch to start with.

The Featherstream also works with both rotations, so if you change engines (Volvo to Beta for instance), you won't need to change the prop.
 
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