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I guess that really depends on whether or not dropping $2500-$3000 on a folding prop is a trivial thing for your wallet...
I replaced my 27 year old Martec folder with a new one this spring. Cost for the new Martec was $650. A new fixed 2-blade would have been about $300. Well worth the difference in sailing performance to me.
 

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The test in Yachting Monthly also shows that folding propellers has less drag than feathering propellers, however both are way better than the fixed propeller they used as reference. The YM test is not really scientific, but a valid test of a number of different feathering and folding propellers. Well worth a read.
Here's a video from the test
YouTube - Folding Props
 

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Folding propellers and lobster pots

I don't get the thing about fixed props being better around lobster pots, I believe that a folding prop would let the lines (and pot) slide by where a fixed prop might catch it?

I realize MS does like the fixed props, something to do with crab/lobster pots, but I'd still take a feathering/folding if racing on a regular basis. Because the PHRF rating hit, is not as bad as the how much slower you go. Usually more like 12-15 secs a mile with only a 6 sec credit, at least here in the NW US.

Marty
 

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When

I don't get the thing about fixed props being better around lobster pots, I believe that a folding prop would let the lines (and pot) slide by where a fixed prop might catch it?
When you hit one under power, or floating line, they can for more fragile than a fixed prop. Been there....$$$$$$$$. As much as I'd prefer to sail 100% of the time in Maine that is not always possible with zero wind days and 3 knots of tidal current against you you do use the iron genny..

If I was racing my own boat I would probably own a Max Prop but I race OPB's. IIt would take me a week of hauling stuff off to get my boat to race weight...:D I now use a Campbell Sailor, and while certainly slower, the few seconds per mile lost vs. a folder/featherer just means a more enjoyable sail...
 

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Point taken, it was actually rather stupid not considering motoring... :eek:

When you hit one under power, or floating line, they can for more fragile than a fixed prop. Been there....$$$$$$$$. As much as I'd prefer to sail 100% of the time in Maine that is not always possible with zero wind days and 3 knots of tidal current against you you do use the iron genny..

If I was racing my own boat I would probably own a Max Prop but I race OPB's. IIt would take me a week of hauling stuff off to get my boat to race weight...:D I now use a Campbell Sailor, and while certainly slower, the few seconds per mile lost vs. a folder/featherer just means a more enjoyable sail...
 

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Discussion Starter · #26 ·
On my old C-36 I had a two blade fixed Michigan wheel. The boat was faster with the prop freewheeling vs. locked in any position. I experimented with this for a full afternoon with some racing buddies who doubted this. In the end they agreed the boat was faster freewheeling sometimes by as much as almost a half knot in lighter winds when we were not already near hull speed.

...Every ounce of credible scientific data suggests that a freewheeling Michigan Wheel style prop causes more drag locked.
This was really what I was looking for... A test that involved actually aligning the blade with the keel. And if you were seeing a 1/2 knot difference in drag, then I have no reason not to believe your results.

Oh, and btw... you're right on the J boat Martech's, (my bad). But I know several J boat skippers that still set the prop shaft orientation even though it's a folding prop.
 

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Oh, and btw... you're right on the J boat Martech's, (my bad). But I know several J boat skippers that still set the prop shaft orientation even though it's a folding prop.
The reason for that is that the lower blade can open due to gravity at very low speeds and increase drag. The correct orientation of a Martec folder when sailing is when the blades would be horizontal if they opened. Only an issue when racing in light air.
 

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Let's see if I can get rid of my last little green box here.

Backcreeksailor

You have a hint of a go fast trick and you bring that trick here and the powers that be say, no way it will work . We have tests that prove it won't work.

But, in this thread is one poster that seems to agree. A glimmer of hope.

This is not Rocket Science.

Mark your shaft and try it, this is a free test.

Maybee you will see some improvement in speed and maybee not but it's not like recuting your main and finding out, that didn't work.

If you find speed gains by fixing your props position don't come back here bragging and saying "I told you so". Put you new found speed secret in you little bag of tricks and hold it dear.

I might even check the rules to see if the prop had to be on the shaft. There might be an advantage to having a fixed prop in the bilge and certainly it would have less drag there than a mounted folding prop on the shaft.

Maybee a 8 inch prop with a big bite would get you to the race course and not cause as much drag as a folding prop and thus not take the hit of a folding prop.

If the wind is blowing 40 knts. and your down to your last reef then I guess this is all for naught.
 

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Oh, and btw... you're right on the J boat Martech's, (my bad). But I know several J boat skippers that still set the prop shaft orientation even though it's a folding prop.
But they do this so the bottom blade does not flop down and cause drag not necessarily to align it behind the keel.. If you align it vertically the blades do not flop open at low speeds..
 
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