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FSmith · 03-05-2014, 09:22

I have a southern cross 35 with a 3 blade fixed prop in an aperture. The prop shaft exits the back of the keel as opposed to being hung off a strut hanging out in the open. The keel is pretty wide and I'm not sure if a feathering prop will offer much improvement in light air sailing. I sail with the tranny locked in reverse but putting it in neutral does not seem improve sailing speed, sooo anyone have experience with a feathering prop on a boat where the prop is located in an aperture? Thanks.

Cheechako · 03-05-2014, 09:32

I had a 44 that the prop was directly behind the keel. However the keel was pretty tapered not thick in front of the prop. I had a Max Prop on it. Unfortunately I didn't use the boat that much prior to the max prop and cant tell you if there was much difference. My sense from other boats with an even more exposed prop is it's not a big difference. The hub of the feathering prop is larger, often the prop is at an angle rather than completely horizontal so even feathered it presents some blade drag.
The thrust in reverse was far better with the Max prop though.

deckofficer · 03-05-2014, 09:55

There are 3 major advantages to using a Max prop. Better sailing performance when feathered, as Cheechako mentioned, better astern propulsion for setting the hook as the blades will pitch for astern propulsion, which leads to the 3rd major advantage. When a Max prop goes from ahead propulsion to neutral and then engine stop, the baldes feather. But if you go from astern propulsion to neutral and stop, the blades stay pitched in astern propulsion, giving you the opportunity to generate some watts by having an alternator on the output shaft. This is a lot handier than the insalling of a second shaft and prop for power generation. I can't take credit for this usage, Steve Dashew and other cruisers from the past came up with it.

msponer · 03-05-2014, 10:53

Just an aside, but we spent the morning trying to sell our MaxProp at a cruisers swap meet here in St Martin (I swapped it for another kind of folding prop and don't need it).

Anyways, I was surprised that most of the people who considered buying it already have a MaxProp. Apparently they have a limited life, the mechanism wears and they get stiff.

Which is fine, but given how expensive they are, maybe its good to know that it may not be a "one time expense" if you are going to keep sailing for a long time.

**Jim Cate** · 03-05-2014, 16:10

Quote:

Originally Posted by msponer

Just an aside, but we spent the morning trying to sell our MaxProp at a cruisers swap meet here in St Martin (I swapped it for another kind of folding prop and don't need it).

Anyways, I was surprised that most of the people who considered buying it already have a MaxProp. Apparently they have a limited life, the mechanism wears and they get stiff.

Which is fine, but given how expensive they are, maybe its good to know that it may not be a "one time expense" if you are going to keep sailing for a long time.

Can't speak for the Max, but the AutoStream (Australian) feathering prop that we had on our previous boat had over 3000 hours on it when sold, and was in like new condition. No slop in the bearings, no wear in the gears, a few scars on teh blades where I was overly enthusiastic with the barnie scraper.

That prop had an external grease nipple, and I was able to do an annual grease job in the water if we were not slipping for paint that year.

Cheers,

Jim

GWB · 03-05-2014, 16:42

I put a max prop on my full keeled boat. It makes a definite difference and I would highly recommend it.

Terra Nova · 03-05-2014, 17:17

Yeah, the Max Prop made a difference on every boat I've installed one, including a full keel Cheoy Lee Lion.

botanybay · 17-05-2014, 09:43

On a cruising cal 35 coming directly out of the back of the keep (which was perhaps 4 inches wide at the stern with a flat back) prop a couple of inches behind.

Installed to stop Borg warner v-drive from spinning after tearing up the transmission in an offshore storm running downwind.

At any rate, speed difference in light air was about half a knot.

What is forgotten is there is an benefit on pointing angle going to weather which is significant.

New boat came with a maxprop.

Never heard of a well maintained max prop wearing out (not to say it is not true). I lube mine once a year in the water. This also prevents internal corrosion.

PYI will rebuild the props to like new.

savoir · 17-05-2014, 10:36

Maybe you would be better off with a folding prop. there are plenty of brands to pick from and all are cheaper than a Max.

lancelot9898 · 17-05-2014, 11:56

I'm sure there is some sort of limited life to the max prop, but I haven't found it yet. When my boat was brand new in 1985, I put the max prop on. It's still going strong today and while I mostly sail rather than motor, I've done several ICW trips from the Chesapeake down to Lake Worth over those years.

redhead · 18-05-2014, 05:16

We had Pearson 365 ketch with a 3 bladed fixed, the boat almost refused to sail in anything less that 13 knots. Occasionally, the rudder would stall at this speed or above. Then we installed the Max Prop. Our first experience out of the slip, the boat made hull speed in reverse, (much to my chagrin..).

The boat sailed to weather better and we notice we started to catch up to boats much younger than ours, but the best part was we were able to sail up and anchor in 1 knot of wind.

We're budgeting now for a Max for our new (to us) Ian Ross 63'. It costs the earth but diesel's even more..

savoir · 18-05-2014, 06:57

Gollygosh ! A Max for a 63 footer would have to cost around $5,000.

redhead · 18-05-2014, 07:10

Quote:

Originally Posted by savoir

Gollygosh ! A Max for a 63 footer would have to cost around $5,000.

Even more - it has a 2" prop shaft we need 26" blades - double your estimate and add more. We have been thinking of having the prop shaft reduced to 1.5" that will halve the price of the prop, but then you add in the price for that process - so in the end it's a toss up.

My point being we REALLY believe in Max Props........we consider the up front expense worth the final fuel saving return. We'll be sailing a heck of a lot more with the prop than without. Of course I;m saying all this before I write the check - this all may change. Cheers