Is it worth it????

Tortuga's Lie · **Joined:** 27 Oct 2006 10:32 **Posts:** 827

I am thinking of replacing my martek two bladed folding prop with a three blade feathering prop but I'm not sure its worth the $$$$$$$$.
The two blade Martek does an adequate job in foward powering up to about 6 1/2 knots but is poor in reverse and obviously the drag won't be a deciding factor. I understand that the feathring props do a decent job in reverse so I'm thinking (not committing yet) of the switch.
Has anyone out there made a similar switch?? And, is it worth it????
Thanks, Tom

berwick · **Joined:** 21 Oct 2006 18:12 **Posts:** 327

I put on the kiwi 3 bladed feathering ($1250) last year and love it. It saved me from running into rocks last summer as I can stop very quickly. The main reason I got it was to stop the bad stern walk, it is still there a bit but a whole lot less. There may be a bit of an increase in speed sailing but last year was my first with the boat so I'm not sure. The prop no longer turns when sailing in neutral. As I said the reverse is great - I would recomend it, here is the link. http://www.kiwiprops.co.nz/

Richard

jammin · **Joined:** 30 Oct 2006 15:40 **Posts:** 63

Practical Sailor did an article on props a couple years ago. Here is what I recall. I don't recall the issue date.

Forward direction:

Of course the 3-blade props were best in thrust versus rpm. The more you fill the "circle" with blade the more thrust. Two blade fixed props were not as good but close.

The next best was the Martec two-blade folding prop! The Auto-prop was almost equal to the Martec.

The 3-blade feathering props were poorest due to the flat blade shape.

Reverse direction:

Again the 3-blade fixed is best due to more blade area.

The auto-prop beats out the Martec here due to the unique reversing blade idea.

I don't recall where the 3-blade feathering prop falls in this category.

Drag is virtually equal for all folding/feathering props.

PS said the lower thrust can easily be offset by increasing rpm on the folding/feathering props.

I feel that if you have trouble stopping your boat in reverse gear, then you were going too fast to start with. You just have to learn to anticipate the stopping ability no matter what prop you have.

I have had several Martec props and have been very happy with them, except for the short life I experienced on an early design geared prop. They have changed the design, and now the prop can at least be reefurbished when it is worn. This may need to be done every 1000 hours of motoring. I wore mine completely out. I now have a SeaHawk folding prop from Martec, and it is better performance.

We find that for cruising we may do more than 60% of our water time motoring or motor-sailing. If it were not for racing our boat I could seriously consider a fixed prop. But the folding prop is a must to race.

So I hope some of this helps.

Jerry
JAMMIN' #226

Tortuga's Lie · **Joined:** 27 Oct 2006 10:32 **Posts:** 827

Its not the stopping the boat, that's fine, It's the control in reverse. Most of the time , she kicks to port, but about 20% of the time she'll go to starboard. I haven't figured out a correlation. The slip I'm in really doesn't have any current issues for its really protected, almost perfectly still and the wind is consistantly from one direction.......

Down2TheC · **Posted:** 22 May 2007 06:31

Back to STBD? Shocked

That shouldn't be possible...

Tortuga's Lie · **Joined:** 27 Oct 2006 10:32 **Posts:** 827

I know it's CRAZY talk!!!.....backing to starboard. Maybe....it's those pesky sea monsters pushing me sideways...or something like that. Shocked

Down2TheC · **Posted:** 22 May 2007 13:12

Are you sure you didn't install a bow thruster you forgot about? Perhaps after a few too many. Cheers

I can't think of any fixed situation of any shape blade that would do that. Only a transmission issue... in which case you wouldn't quite back to stbd.

Either way... watch out for the feathering 3-blades. A neighbor with the Atomic put on on his T37 and if you put it in gear at idle, the engine would stall. (discovered while pulling in with 30kts on the stern Shocked

) The Westerbeke seems fine with it according to other posts.

Personally, I'd hate to lose the stern walk. I use that quite often to make things happen that might not otherwise be possible.

Tortuga's Lie · **Joined:** 27 Oct 2006 10:32 **Posts:** 827

I would like to rely on that kick to port, and for the most part I do, but there is that occasion when she'll go to starboard and throw things off.......It must be that bow thruster!!! Boat Drinks

Tartan37.com

Is it worth it????

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