Folding Prop

[SDS3 Sailors]

2005 H36 with Yanmar 3YM30. I am considering a folding prop and have a fact question and an opinion question:

1. (fact) what is the size (diameter) of the standard Hunter shaft on this boat? Can not find it in documentation.
2. (opinion) for those who switched from a conventional to folding prop, was it worthwhile?

With a Hunter 36 we are a cruiser, rather than a serious racer. Thanks in advance for any insights.

 

[Don S/V ILLusion]

1. No clue
2. a huge difference in terms of less drag as well as less prop walk and more backing power.

 

[Davidasailor26]

(opinion) for those who switched from a conventional to folding prop, was it worthwhile?

Yes, without a doubt. Much better sailing speed (a solid half knot, especially at low wind speed). Also so much quieter when sailing without the prop freewheeling. Prop walk in reverse is about half - enough to still be able to use it when we want to but not overpowering.

 

[Georgedoyle]

I agree with previous comments. I can add that my boat steers much better while sailing. It takes a lot less effort to keep the boat locked onto its course.

 

[Davidasailor26]

I agree with previous comments. I can add that my boat steers much better while sailing. It takes a lot less effort to keep the boat locked onto its course.

Same here. I didn’t mention it because I didn’t know if that was just a Beneteau characteristic, but our steering is much more controlled with the folding prop. The fixed prop was creating lots of turbulence in front of the rudder and causing rudder stalls and rounding up if we weren’t careful in higher winds. With the folding prop we can sail in winds about 5 knots higher before we have those issues.

 

[quadrille38]

2005 H36 with Yanmar 3YM30. I am considering a folding prop and have a fact question and an opinion question:

1. (fact) what is the size (diameter) of the standard Hunter shaft on this boat? Can not find it in documentation.
2. (opinion) for those who switched from a conventional to folding prop, was it worthwhile?

With a Hunter 36 we are a cruiser, rather than a serious racer. Thanks in advance for any insights.

I would recommend a feathering prop over a folder. Likely a bit more costly but feathering is far less likely to experience what folders can - they sometimes fail to unfold when shifted into reverse at a very critical need to stop now moment.

 

[dlochner]

Prop walk in reverse is about half - enough to still be able to use it when we want to but not overpowering.

As others have said, there is a ½ knot or better improvement in speed. That doesn't sound like much, however consider that it is a 10% improvement at 5 knots. On a 50 mile leg that's an hour less sailing time which is especially important when that T-storm is chasing you.

Propwalk depends on the particular folding or feathering prop. Max-Props are known for good forward speed, good feathering, and lots of prop walk in reverse. The increase in propwalk is only exciting the first few times, then you learn how to use it to your advantage.

 

[kappykaplan]

lots of prop walk in reverse. The increase in propwalk is only exciting the first few times, then you learn how to use it to your advantage.

Yes, I use this to my advantage every time!

 

[George Braun]

2005 H36 with Yanmar 3YM30. I am considering a folding prop and have a fact question and an opinion question:

1. (fact) what is the size (diameter) of the standard Hunter shaft on this boat? Can not find it in documentation.
2. (opinion) for those who switched from a conventional to folding prop, was it worthwhile?

With a Hunter 36 we are a cruiser, rather than a serious racer. Thanks in advance for any insights.

On my 2008 H36 the propshaft is 1". Bought a 3/4" anode, had to go back to WM

 

[Hollyberry]

I would not say that a FOLDING prop gives you better reverse thrust - it depends on the model and design. A FEATHERING prop, OTOH, is miles better than fixed (for sailing) or folding (for reverse), but also rather more costly. We put a 3blade MAX prop on our last boat... loved it. Current boat has a 3 blade Kiwi feathering prop, less costly, slightly clunky design compared the the MAX prop's slick engineering (the MAX can be set up for either rotation and pitch adjusted.. the KIWI is directional) Composite blades of the Kiwi minimize corrosion/electrolysis issues.
Geared folder much better than non.
I'd consider the cost of a good folder as a down payment towards a Feathering prop.. you'll forget the extra cost soon down the road.

 

[Rick D]

2005 H36 with Yanmar 3YM30. I am considering a folding prop and have a fact question and an opinion question:

1. (fact) what is the size (diameter) of the standard Hunter shaft on this boat? Can not find it in documentation.
2. (opinion) for those who switched from a conventional to folding prop, was it worthwhile?

With a Hunter 36 we are a cruiser, rather than a serious racer. Thanks in advance for any insights.

I put on a two-blade geared folding prop about 17 years ago. It really makes a difference in noise (you don't have to let the prop free-wheel), light wind performance, and pointing ability. My old prop looks good on the fireplace mantle too. BTW, backing is just fine; you do need to use more RPM, but it performs just fine. Yes, I used to race a lot, but havent in years, and I would definitely have one for cruising.

 

[jssailem]

Hi SDS3.

1. (fact) what is the size (diameter) of the standard Hunter shaft on this boat? Can not find it in documentation.
   1. That is what calipers are for. To help you measure your shaft when the boat documentation is weak. Even a cheap tool from Amazon will serve the purpose if it is for a zinc replacement.
   2. You might try the experimental approach. Buy a 3/4" and a 1" zinc returning the one that is the wrong size.
2. (opinion) for those who switched from a conventional to folding prop, was it worthwhile?

I cruise in waters that have serious tidal currents and passages that require optimum power and planing to safely navigate. While I try to sail more than I power, if the winds are died being caught in a tidal rip is not an option. My researched led me to the CampbellSailor (CS) prop. It favors the power side over the sail side at a cost 50% lower than a foldable prop. If I was racing, then I would have gone the fold/feathering prop direction.

The CS prop has given me a 1.3 knot improvement in thrust under power with a 20% reserve. My sailing speed has improved as well by about .6 knots over the previous prop.

What ever you choose it will be a compromise of cost/sail/power performance.

 

[George Braun]

Hi SDS3.

1. (fact) what is the size (diameter) of the standard Hunter shaft on this boat? Can not find it in documentation.
   1. That is what calipers are for. To help you measure your shaft when the boat documentation is weak. Even a cheap tool from Amazon will serve the purpose if it is for a zinc replacement. View attachment 214745
   2. You might try the experimental approach. Buy a 3/4" and a 1" zinc returning the one that is the wrong size.
2. (opinion) for those who switched from a conventional to folding prop, was it worthwhile?

I cruise in waters that have serious tidal currents and passages that require optimum power and planing to safely navigate. While I try to sail more than I power, if the winds are died being caught in a tidal rip is not an option. My researched led me to the CampbellSailor (CS) prop. It favors the power side over the sail side at a cost 50% lower than a foldable prop. If I was racing, then I would have gone the fold/feathering prop direction.

The CS prop has given me a 1.3 knot improvement in thrust under power with a 20% reserve. My sailing speed has improved as well by about .6 knots over the previous prop.

What ever you choose it will be a compromise of cost/sail/power performance.

I second the Campbell Sailor - upgraded our previous boat. 1977 Islander 32. Original aux power was Atomic 4, PO re-powered with a Westerbeke 18hp diesel but neglected to change out the 9X9 2 blade prop. for $600 a few years ago we put a Campbell Sailor 3 blade, gained a knot under power with no impact to sailing speed. Already have a quote from them for our new 2008 H36 for a 16X9 3 blade at $785 plus $58 frt. Replacing the current big fat inefficient 3 blade I anticipate gaining a knot under power and at least a half knot under sail.

 

[tfox2069]

- H36 shaft is 1"
- Switching from fixed three-bladed prop to Flex-o-Fold 3-blade was one of the best upgrades to my 2009 H36 I ever did.
- Do a search on "Folding Prop" in the forums and you'll get lots of good info and opinions
- Check out the actual data from one Flex-o-fold owner in this thread: Folding Prop Verdict | Sailboat Owners Forums
- Also, Campbell Sailor owners are universally enthusiastic about that fixed prop choice

 

[Hollyberry]

Over the years we have run a Martec folder, Campbell Sailor, Fixed wheel, Maxprop, and now Kiwi.
The old martec (not geared) was occasionally scary when only one blade opened when put in gear. The Campbell was slightly slower but reliable and much less drag than a 'michigan wheel.
The Max was the ultimate - beautifully engineered and fully adjustable for pitch and rotation. Our current Kiwi seems to be working as well as the Max but not as pretty on a haulout!