Prop Comparisons

[Loren Beach]

We are (Gasp!) contemplating a change to a three blade (perhaps ... fixed) prop.
Everyone in the marine industry tells me that we can reduce (some or) most of our motoring vibration by changing from a two to a three. I have enjoyed the straight-line reversing and low drag under sail from our existing Martec "Autostream" two-blade featherer, since 1995.

What with the new price for a three blade, Maxprop or Autostream, being about $2600., this is really more than our budget allows.
A three-blade fixed prop will be about $600.
Since we do not race competitively and do indeed motor quite a bit in this part of the NW, a fixed prop is not out of the question...

I hope that we do not end up with prop walk in reverse, though.

Opinions seem mixed on the cheaper Kiwi prop, and also for the untraditional Campbell Sailor 3-blade fixed prop with its skinny blades.

At the risk of seeming to mix apples with oranges in these comparisons, I am looking for opinions on all of 'em. The comparisons may be "unfair" in some ways, but yet this is the sort of decision that most sailors probably have to make.

As to "why now?" -- I found that last weekend while doing the annual opening day parade nonsense we had lost almost a knot of speed forward. With the Autostream that usually means that the lock-nut on the forward adjusting screw has loosened up. Boat needs to be hauled promptly to fix this. In the spring 40 degree 2.5 kt run-off current, no one is going into the Columbia River to adjust this!
So, if we gotta pay for a boatyard round trip, it's a good time to revisit the prop question before vacation starts a month from now.

All opinions welcome, even the ones I don't like...


Thank you,
Loren

ps: I better stop bragging about our "boring" Oregon weather; someone was killed a mile from my house Saturday afternoon by a falling tree impacting a moving car, courtesy of a short but violent wind/rain/lightning event. It rained buckets for about 20 minutes and knocked out power to 30K homes on the west side of the city.

 

[missalot]

Hi Loren,

I've done the 3 blade thing on my e29. I have a Universal 5424 (yes, way more than I need). I started with a 14x12 Michigan 3 blade that had about 30% of the blade area removed. Motored great, backed up to port, but did bite real well. Next was a Campbell Sailor, 15x9. Motored great, not as much backing to port - less drag. Now in search of less drag for racing, I have changed to a KIWI prop. So far I love it, noticably less drag. But have only had it on since Feb. - only a handful of trips.

Not sure how big of prop you need, but I can part with the Michigan prop, it's right hand, 1", standard taper. Make me an offer.

 

[Loren Beach]

Local prop builder sez I should have a 15 X 10 in a three blade.
(11" pitch would be OK for a two blade).
Looks like a 12" pitch would be way too much for a three blade.

I once had a 15 X 12 two-blade on this boat and it was way over-propped.

Thanks for the offer. Much appreciated.

Regards,
Loren

 

[missalot]

no problem, you might ask your prop guys if they can "beat" this one into submission.

I'm guessing about $60 will include shipping via UPS from Anacortes to your place if you change your mind.

 

[Chris A.]

Flex o fold

Loren,

I've been contemplating similar issues and I'm leaning toward flex-o-fold. Can't decide on the 2 or 3 blade folder- they have interesting data on their website and the North American rep (can't remember his name right now- Tim R will know it) has been informative and service oriented. They are priced less than some and the props I examined at the Annapolis show are beautifully engineered. The two blade is on Tim R.'s E35-III Cordelia and I can say it performs very nicely under power and sail.

I also sail on a friend's E34 with a 2 blade max prop and can't say I like it as much as the flex-o-fold, although the reverse will nearly shake you off the boat.

FWIW,
Chris

 

[Rhynie]

Loren,
I can sympathize, just went the busted prop routine myself. We unknowingly snagged a crap trap and when we cranked up the engine...Oh well! The prop was obviously brittle and lost about 1/2 of one blade and 1/3 of the other, will try to attach a pic, not done that yet! i tried diving it, but was to muddy and dark so ended up having to haulout.

Anyway, I got a suitable prop locally, but in searching I found several on Ebay (hard to get the search correct) and Minneys has a bunch also.

The joys of boat ownership!

 

[Rhynie]

Loren,
The attachment worked well, but I attached the wrong pic. That one was the dive attempt, you can see how dark the water is, was keeping an eye out for Willie also, the local 8 1/2 alligator.

Anyway, second attemp here at the prop pic.

 

[lbertran]

Campbell Sailer

We went to a Campbell Sailer three blade late last year so we've only had it for a few weeks last year and two times out this year. So far, we're very pleased. We like to sail fast and we still do. Motoring seems better in all ways, more close maneuvering control, more backing control, and more bite in head seas. Vibration was one reason we switched and this prop has made a large difference. Though any motor running is too noisy for me

 

[Shadowfax]

Rhynie,

That must have been one hell of a crab pot by the looks of that picture.

 

[ted_reshetiloff]

All that pink colored metal in that prop is the result of some serious electrolosis going on. You should check into that. When ever bronze starts to turn pink or that brick red its generally a sign of galvanic action.

FWIW I run a 2 blade feathering max prop.Vibration is no different than the 3 blade fixed prop (bucket) I took of 5 years ago. Loren is your current prop a folding or feathering? And has it always vibrated badly? Maybe it needs to be rebuilt?

I wanted to get the 3 blade max but the third blade was another $1,000. Just not worth it to me, but maybe I dont motor as much as you.

 

[Loren Beach]

All that pink colored metal in that prop is the result of some serious electrolosis going on. You should check into that. When ever bronze starts to turn pink or that brick red its generally a sign of galvanic action.

FWIW I run a 2 blade feathering max prop.Vibration is no different than the 3 blade fixed prop (bucket) I took of 5 years ago. Loren is your current prop a folding or feathering? And has it always vibrated badly? Maybe it needs to be rebuilt?

I wanted to get the 3 blade max but the third blade was another $1,000. Just not worth it to me, but maybe I dont motor as much as you.

We have a two blade Martec Autostream feathering prop now. Installed in '95, when it cost a mere $975. (!) Back then a three blade was about $1700. I wish I had spent the extra money for that third blade....

Current prop has been sent in a couple of times to Martec for refurbishing over the years, as a preventative maintenance idea when the boat was out already for a bottom job. I just had morning coffee with my sailor / retiree group and owners of two blade Maxprops and another Autostream all say that trying both a two and three, the three blade produces noticeably less vibration.

Agree about the dezincification that seems evident in the photos of the other boat. Must be some stray current in that boat's slip area. That'll end up as a weak copper propeller. And, that's in addition to being eaten by an alligator if you go into the water.

As to how much we motor, that's the "dirty little secret" about sailing in the NW. Lots of light air days and quite a few of those with no wind. It's no wonder that the richer portion of our sailors end up with Nordic Tugs!

Cheers,
Loren

 

[ted_reshetiloff]

I would certainly agree that the 3 blade feathering should be the best in pretty much every area. I do recall an article in last months Sail magazine where Nigel Calder was doing some testing of I think the Gori prop and had some interesting comments. Apparently the new Gori's have 2 pitch settings in forward. Sort of like a second gear or something. It has to do with the way diesels hp and torque curves work. I cant recall the details but if I were looking into new feathering props I would take a look at the gori and last months Sail. It seemed like you could reduce fuel consumption and imrprove power by "shifting" the prop to this second forward pitch setting once motoring at speed.

 

[Loren Beach]

After considering the very gracious offer of the 14" used prop... I decided to order the new three blade 15". It should be ready next Monday and the plan is to install it Tues.

LB

 

[Rhynie]

Loren, Ted,
The crab traps used around ere are metal, sort of like hog wire with vinyl coating. My suspicion is that the line wrapped up, pulled the trap up to the prop, and the trap won out over a brittle prop. The leading edge of the rudder had deep scratches, like sharp wire ends got to it. That or fingernail scratches, bayou monster or Willie!

On the 'pink', yes, very much aware of electrolysis issues and following up on it. Coincidentally four other boats in vicinity of my slip have had recent issues, and marina is investigating also.

Anyway, we are back operational, raced last weekend, and managed third out of a fleet of nine. A J-80 ran away, and a Catalina 36 beat us by just over two minutes corrected over 14 1/2 miles, but we beat her boat for boat. Not too shabby for an old lady!

 

[Captron]

J Prop

We installed a J Prop 3 blade feathering type on Kismet 5 years ago. It works great. Zero prop walk lots of reverse power. Did I mention lots of reverse power? I chose it for two main reasons. The pitch can be adjusted by hand, underwater, very simply, and it attaches to the (almost) stock shaft just as an ordinary prop does. In other words you don't have to have 4 arms and 3 wrenches all going at the same time to avoid dropping parts. I've adjusted our pitch several times searching for the right angle ... about 9.5 or 10 inches seems about right.

All that said and as much as I like it, I wouldn't waste the cash on a do-over. I've said it before, on a cruising boat, simpler is mo' betta'. Besides there's lots of other places to burn boat-bucks and get something that you can actually play with once in a while.

One issue with all folding and feathering types is keeping them very clean. Small amounts of crud can prevent them from working as well as they should. The special zincs ain't cheap either.

If I were to do it over, I think I would install a standard two blade fixed prop like the boat came with from the factory. I have a friend with an E-38 that has the stock fixed two blade and he can motor faster than I can in the same conditions. Of course, his reverse pretty much sucks. He's the entertainment anytime he has to dock using reverse.

Then again on a cruising boat we pretty much hang on the hook so docking isn't that much a percentage of our time on the water.

For cruising, I say go with a properly sized fixed prop two or three blade. In fact, find a clean used one on CraigsList or EBay.

 

[ted_reshetiloff]

Capt. Ron is spot on here. I did choose the Max prop mainly based on a longstanding reputation and lack of bad comments. Also that the company has been around for a long time and hopefully will continue to support their products. I picked up just over 1/2 of a knot sailing verses the fixed three blade so that over a 24 hour period is 12 miles? Probably not that big of a deal on a 2 or 3 day cruise. Overall I have no buyers remorse on the max prop and will certainly put one on my next boat...

 

[Chris A.]

I could go for that...

I could go for that 1/2 knot of sailing speed!

 

[treilley]

As Chris said, I am very happy with the sailing and motoring performance of my flexOfold. Chuck Angle is the US rep in Marblehead, MA. Very nice and knowledgable guy. Deffinitely worth speaking to about props.

 

[EGregerson]

prop shop

when you're contemplating swapping around props, do you usually stay with the original diameter? e.g. i have (probably the original) 15 x 11 2 blade on my e34. if i went to a 3 blade, should i stay at 15; or can i drop to a 14"?

 

[Emerald]

If you went from a 2 to a 3 blade, all else equal, you would go to a smaller diameter. Here's a nice little prop 101 write-up from a place that did a shaft for me a ways back:

http://a1discountprop.com/propinfo.htm