Folding / Feathering Props
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Opinions...
We put on a Martec feathering two blade in about '95. Low drag under sail and almost straight backing from a standing start.
You do have to grease it thru the grease fitting and put on a proprietary cone-shape zinc every two or three years (we are in fresh water...).
Also you have to put the right grade and brand of white grease in (same goes for the PYI MaxProp) if you boat in cold water... The blades need to easily rotate 180 when you change directions with the transmission.
Presently we are trying out a three-blade "sailor" fixed prop -- just to see how we like the extra torque when we need to motor into a chop. Second season on this experiment, and our boat motors like a trawler into any chop.
Price paid is about a one knot loss at all sailing speeds. We kind of expected that, but it is definitely a big price you pay. Reverse has gone back to the old port walk. After owning the boat so long, I can compensate to a fair degree, but still...
When the budget improves, I see a feathering three-blade in our future. Then we would have the low drag under sail and the blade area under power. "It's only money" as they say.
There are some good threads on this topic with input from a several owners over at the ericson owners' site, FWIW.
Regards,
LB
We put on a Martec feathering two blade in about '95. Low drag under sail and almost straight backing from a standing start.
You do have to grease it thru the grease fitting and put on a proprietary cone-shape zinc every two or three years (we are in fresh water...).
Also you have to put the right grade and brand of white grease in (same goes for the PYI MaxProp) if you boat in cold water... The blades need to easily rotate 180 when you change directions with the transmission.
Presently we are trying out a three-blade "sailor" fixed prop -- just to see how we like the extra torque when we need to motor into a chop. Second season on this experiment, and our boat motors like a trawler into any chop.
Price paid is about a one knot loss at all sailing speeds. We kind of expected that, but it is definitely a big price you pay. Reverse has gone back to the old port walk. After owning the boat so long, I can compensate to a fair degree, but still...
When the budget improves, I see a feathering three-blade in our future. Then we would have the low drag under sail and the blade area under power. "It's only money" as they say.
There are some good threads on this topic with input from a several owners over at the ericson owners' site, FWIW.
Regards,
LB
On our previous boat, a Pearson 32, I replaced the three-blade fixed prop with a Flex-o-fold two-blade. It was expensive, almost $1000, but the performance increase under sail was worth it for me. I figure I gained on average around half a knot. An added benefit - not to be overlooked - was the ability to shed crab trap lines, which are a menace where I live. I can't say I saw that much difference in performance under power compared to the fixed prop, in either forward or reverse, or in terms of prop walk. The prop itself was very well made, really a bronze work of art, and I would highly recommend the manufacturer.
When we bought our current boat it already had a two-blade Maxprop feathering prop on it, which seems to do a good job, although this time I don't have a basis for comparison. I'm a little concerned about crab traps, since the blades still stick out instead of folding back, but I haven't snagged one yet. A nice feature of the Maxprop is the ability to adjust the pitch, if you are willing to haul the boat out, but the one outstanding feature is the amount of thrust in reverse. Wow! I mean, the boat has brakes now. You have to make extra sure the shaft won't pull out of the coupling, because the prop is really applying some force there. I didn't buy the Maxprop, but I understand it's even more expensive than the Flex-o-fold. It, too, is a finely crafted piece of machinery.
If you would enjoy extra speed under sail, by all means get rid of that fixed prop. What you replace it with depends a lot on your wallet and personal preferences.
When we bought our current boat it already had a two-blade Maxprop feathering prop on it, which seems to do a good job, although this time I don't have a basis for comparison. I'm a little concerned about crab traps, since the blades still stick out instead of folding back, but I haven't snagged one yet. A nice feature of the Maxprop is the ability to adjust the pitch, if you are willing to haul the boat out, but the one outstanding feature is the amount of thrust in reverse. Wow! I mean, the boat has brakes now. You have to make extra sure the shaft won't pull out of the coupling, because the prop is really applying some force there. I didn't buy the Maxprop, but I understand it's even more expensive than the Flex-o-fold. It, too, is a finely crafted piece of machinery.
If you would enjoy extra speed under sail, by all means get rid of that fixed prop. What you replace it with depends a lot on your wallet and personal preferences.
I have a Kiwi and like it. Same improvement in sailing performance as Sandy reported on the Pearson. It doesn't motor as well as the fixed 3-blade it replaced, but then I don't motor well either, would rather be sailing.
I've had two boats with Martec folding two blade props, another boat with a different folding pro (also two blade) (sorry, can't remember what brand of prop) and my last boat and my present boat--both had/have a three blade Max prop.
I'm quite sold on the Max feathering prop. The three blade seems to get me through chop better then my old two blade props. Also the three blade seems to make the engine much smoother. Although I now have a 2 cylinder Yanmar, it runs quite smoothly with the three blade. For longish trips this helps me from getting too tired.
Anyone with a Max prop will tell you that the reverse is outstanding and as an added bonus you have very little prop walk...if any. I tend to get cocky docking my boat under power--backing into the slip? Piece of cake.
Downsides to the Max prop. First, it is expensive however, I believe when you sell your boat you'll get that money back. Look in the classifieds on boats and see how many list the Max prop as a selling point. Another negative is that you have to grease the prop at least once a year. I have a dive company who is comfortable with the Max prop and does the lubricatin as well as change the special zinc. I change the zinc every six months.
I have hit crab pots but was moving in slow speeds so I had no damage to my the Max prop. Under sail we seem to move about a knot faster but I really have no comparison or data to support my claim. It just seems that way.
I'm not knocking any other props however I'm sold on the Max three blade prop and believe it to be one of the best items I've added to my present boat. I wouldn't have another boat without this type of a prop. By the way a number of boats made in Europe (Swan, Oyster, Hainse) come standard with Max props.
Hope this helps.
I'm quite sold on the Max feathering prop. The three blade seems to get me through chop better then my old two blade props. Also the three blade seems to make the engine much smoother. Although I now have a 2 cylinder Yanmar, it runs quite smoothly with the three blade. For longish trips this helps me from getting too tired.
Anyone with a Max prop will tell you that the reverse is outstanding and as an added bonus you have very little prop walk...if any. I tend to get cocky docking my boat under power--backing into the slip? Piece of cake.
Downsides to the Max prop. First, it is expensive however, I believe when you sell your boat you'll get that money back. Look in the classifieds on boats and see how many list the Max prop as a selling point. Another negative is that you have to grease the prop at least once a year. I have a dive company who is comfortable with the Max prop and does the lubricatin as well as change the special zinc. I change the zinc every six months.
I have hit crab pots but was moving in slow speeds so I had no damage to my the Max prop. Under sail we seem to move about a knot faster but I really have no comparison or data to support my claim. It just seems that way.
I'm not knocking any other props however I'm sold on the Max three blade prop and believe it to be one of the best items I've added to my present boat. I wouldn't have another boat without this type of a prop. By the way a number of boats made in Europe (Swan, Oyster, Hainse) come standard with Max props.
Hope this helps.
Max prop fan
I changed from a fixed 3 bladed wheel to a max prop last season. The 3 blade classic model. I am very happy with it. It is easy to service your self. Lots of parts but straightforward to do. Good videos online to show you how to do it.
It made a big increase in my speed while sailing in light air.
I changed from a fixed 3 bladed wheel to a max prop last season. The 3 blade classic model. I am very happy with it. It is easy to service your self. Lots of parts but straightforward to do. Good videos online to show you how to do it.
It made a big increase in my speed while sailing in light air.
Kiwi prop here, changed from a fixed two blade. Happy so far, sailing improved, motoring got smoother (3 vs 2 blades) but I don't think any faster. Pitch is adjustable though so might increase it next haulout.
Kiwi seems to be your cheapest feathering option. Blades are plastic, err I mean engineering composite, and are individually replaceable. Does give light weight and low corrosion.
Kiwi seems to be your cheapest feathering option. Blades are plastic, err I mean engineering composite, and are individually replaceable. Does give light weight and low corrosion.
i have a two-blade geared folding Slipstream prop which I love. It is S/S, and so, needs no zinc other than the usual shaft zinc. backs well, powers about the same as the OEM two blade. Sailing is vastly improved! It is distributed through Martec. BTW, a lot of SoCal sailors have the Slipstream feathering three blade and love them.
With just about any folding or feathering prop you'll see a significant improvement in light air sailing performance. I recall when we had to temporarily put our two-blade fixed prop back on because our Martec folding prop was malfunctioning. (Needed rebuilding.) Our PHRF rating was adjusted up by 12 and that didn't nearly compensate for the performance loss.
But...
Folding/feathering props do add complexity and another point of failure. Most cruisers I know will have nothing to do with them, because they don't want to chance a malfunctioning prop when they need it to work. When our Martec failed, we couldn't do more than 4-1/2 kts in relatively calm water w/no headwind (normally we can do 6+ easily), as attemts to go above that would simply set the thing to cavitating. And reverse was nearly non-existant.
Feathering vs. folding is going to partially depend upon your cruising grounds. In Lake St. Clair, where we sail, there are lots of weeds, much of them floating. A feathering prop would make a good weed catcher. A folding prop, OTOH, not so much.
For a folding prop: Geared or non-geared. Again, it's trade-offs. A geared folding prop is going to guarantee symmetrical deployment. But they're more maintenance-intensive and have more to go wrong with them.
Our two-blade, non-geared Martec works well for us. (I should've given it some grease this year, before splashing, and didn't, tho.)
Jim
But...
Folding/feathering props do add complexity and another point of failure. Most cruisers I know will have nothing to do with them, because they don't want to chance a malfunctioning prop when they need it to work. When our Martec failed, we couldn't do more than 4-1/2 kts in relatively calm water w/no headwind (normally we can do 6+ easily), as attemts to go above that would simply set the thing to cavitating. And reverse was nearly non-existant.
Feathering vs. folding is going to partially depend upon your cruising grounds. In Lake St. Clair, where we sail, there are lots of weeds, much of them floating. A feathering prop would make a good weed catcher. A folding prop, OTOH, not so much.
For a folding prop: Geared or non-geared. Again, it's trade-offs. A geared folding prop is going to guarantee symmetrical deployment. But they're more maintenance-intensive and have more to go wrong with them.
Our two-blade, non-geared Martec works well for us. (I should've given it some grease this year, before splashing, and didn't, tho.)
Jim
I have an "autostream" prop on my Elite 37 for over 10 years. It is stainless and has required minimal servicing over this time. It's easy to grease and change the zinc. You can adjust the pitch for your particular engine and backs with nearly the same power as in forward. Last year on haulout, I took the prop apart and checked the gears and seals and it showed no observable wear or tear. Customer service and support has also been great. Cost is a little high but well worth the extra bucks.
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