Maxi-props?

[2divers]

Ok, breaking in a new forum.... ahhhhhh...

For those who are using a maxi-prop ( or don't like it) I've heard that they are very good! Is it worth while setting aside cash to buy one for a boat before I leave?
I'm trying to put together a budget of things I NEED and things that would be a very good idea to have and things that are just plain useful and cost scads of money that I could probably do without....

thoughts?

2divers

[S/V Elusive]

2Divers - I have a maxprop on my boat. I think it is outstanding even though it is one of the older ones that you cannot (safely) change the pitch while it is in the water. The newer ones can be set, tested, reset, and so on until you have achieved the REAL proper pitch for your boat and power train.

I made the mistake of inproperly changing the pitch on my last haulout and had to be re-hauled to set it back - an expensive lesson.

[2divers]

Thanks Thomas!

I was thinking that this one was of those items that would pay for itself in the 'made life easier to deal with' catagory. Do you pull the prop yourself (and have the puller) or just have the marina crew do it?

2divers

[jstevens]

2divers,
I also have a Maxi-Prop and am happy with the choice. It is also type that cannot be adjusted in the water. Fortunately I have not had to change the pitch. You don't say why you might want a Maxi-Prop. They are very expensive, even a used one. My reasons for going with Maxi-Prop were three fold:
1. My fixed prop free-wheeled above 4 kts. To stop it I either had to add a prop brake or a feathering prop. I chose the prop.
2. The Maxi-Prop has a reputation of greater performance in reverse than a fixed prop. This seems to be true, but it was not a dramatic change.
3. I wanted to improve the light air sailing characteristics of my boat. I guess this helped, but I have no objective measurements to prove it.

So I believe the Maxi-Prop delivers what the manufacturer claims and I am satisfied that I got decent value for my expenditure.

John

[ronbo1]

Just this Spring I installed a 19" Max-Prop VP which can be pitch adjusted underwater. Still testing but it seems to significantly improve speed in light winds. Reverse thrust is, of course, better.

It's a well designed and built propeller but if you're installing it yourself make sure you understand completely the rather poorly written instructions. Dry fit it before greasing. You don't want to have to pay for another short haul.
If in doubt the phone support is good.

[roverhi]

Variable pitch props offer real benefits and appear to be very reliable. They are not necessities, however. The problem is cost. You could buy a couple of new sails or spend many more months cruising for the cost of one of these props.

You don't NEED one, but if your budget allows, they are nice to have. Personally, it would be way down my list of additions to the boat.

Aloha
Peter O.

[Boracay]

While the discussed advantages of a feathering prop seem to be slight the advantage that I would look for is that one could get away with a much smaller engine.
Mostly a larger engine is fitted to push the boat against wind and wave.
Theoretically a small engine with a feathering prop could do a better job than a large engine with an incorrectly pitched prop.
So instead of spending (say) $25,000 on a 100hp engine with a fixed pitch prop one could spend (say) $15,000 on a 40hp engine with a feathering prop.
Possibly the only loss would be in top speed with major gains in fuel economy and long term operating costs?

[S/V Elusive]

2divers

As I have the type that you cannot pull while in the water, I presume that meant pulling it while in the yard. All it takes is a needle nosed plier (to pull some cotter pins) and a couple of hex keys (allen wrenches). Depending on how long it has been - maybe a flat blade screwdriver to pry the halves apart. Adjustments are like a cipher .. Match the Capital A to the number 5 and the lower case z with the number 2 and you have 22 degrees pitch (NOTE: this is not an actual example - but it is representative).

You should be able to install one by yourself with minimal tools needed. As noted, the instructions could have used a better technical writer. Also, as noted, their phone technical support is good. When I screwed up (or down as the case was) they were able to figure out what I had done, and set me straight - had their instructions been clearer and with notes pointing out a few additional things, their phone support wouldn't have been needed.

As a humorous aside, the $*&)&#$$@# previous owner didn't have a clue as to what type of prop he had - if he did, he would have been touting it with a corresponding increase in his asking price.

As for performance - I think that I could increase the pitch and increase my speed vs. rpm. But it works very well. Reverse is very good, with light to moderate, but consistant prop walk until there is enough flow across the rudder. Anyone who doesn't like (or know how to use prop walk) hasn't tried to manuver a larger boat with a full to partial cutaway keel - I don't need no stinking bow thruster.

[2divers]

It's good to hear so many good reviews especially on the backing issue. Since I have some time till I leave, I see if I can set aside some cash to buy and install one before I leave... I sounds like I really need to invest in one that can be adjusted underwater vs hauling out, I am after all a diver, so that should not be to difficult to do.... well, minus the decoder ring special Thomas mentioned......;p

[Steve Rust]

One option would be to spend about 1/2 the money and buy a folding prop say from Flex-o-Fold or other reputable suppliers. My take on the pros and cons of folding props verses feathering props is that folders if properly sized are more efficient in forward and reverse due to the more efficient blade shape. Feathering props tend to have a flatter blade shape thus less efficent but many have the ability to change pitch so that is a plus. The feathering prop is more expensive. complicated , and has more parts to wear out. I intend to get a three blade Flex-o-Fold for my trimaran to replace my very nice two blade folder mainly because I need to get the maximum efficency out of my small 17 hp diesel. The key is to get it sized right the first time.

Thomas and I had some good conversations with the prop guys at Strictly Sail this year. What I got out of it is everybody's product is better than everybody elses, and the folding props are better than the feathering unless you are talking to someone selling the feathering prop. It was like a political campaign. One guy saying the other stole his design. The other saying the next guy's design won't back up, and so it goes. FWIW, the Maxi Prop seems to be the standard by which all others are compared. While they all claim to be better, the Maxi is what they claim to be better than. The new Maxi Prop with the splined spring loaded hub to make adjustment easy seems to be the way to go.

[GordMay]

Originally Posted by Kai Nui

...FWIW, the Maxi Prop seems to be the standard by which all others are compared. While they all claim to be better, the Maxi is what they claim to be better than...

Very perspicacious observation.

[2divers]

Originally Posted by GordMay

Very perspicacious observation.

I'm not quite sure what perspicanious.... perpspicanius.... what ever it means, but it sounds goods!

2divers

[GordMay]

Perspicacious* not only “sounds goods”, it is good.
* astute or shrewd

We have the old style three blade max prop on our sloop. Installed it when we repowered. Love it. The reversable pitch makes backing a piece of cake (our sloop typically had real trouble backing with the fixed blade). The adjustable pitch is great. It took us two adjustments to dial it in with the new engine.

My one complaint: zincs. The material that keeps the zincs bolted to the prop is thin. When that is gone, the rest of the zinc flys off. Time for a new zinc.

We have a diver that will change zincs and adjust pitch in the water.