E 30+ Prop Replacement

[tilwinter]

I am very tired of my boat's inability to back up in a straight line, and am giving serious thought to a folding or feathering prop.

Do any of you 30+ owners have any experience with this?

I talked at length to the marketers of Variprop/Varifold, and the Varifold two blade (they say) would both enhance my sailing (this seems obvious, by reducing drag), as well as enhancing both forward power and backing without prop-walk.

Thanks for the input

 

[Loren Beach]

If you do a search on< feathering prop >, you will find some good discussion and a picture of the one on our boat. Not the brand you mentioned, however.

Best,
Loren

 

[escapade]

30+ props

I put a Martek 2 blade folding on my 30+ w/16 hp. diesel. Increased dia. by 1 inch & pitck by 2 inches as I recall (per Martek recomendations). Increased thrust in both forward & reverse although didn't do much for the prop walk. I found that by accelerating slowly & then backing off the throttle when backing I could steer fairly well. Steering under power in reverse untill you have some speed on is difficult on this size boat regardless of prop configuration. All in all, was very satisified with the Martek. I found I could use prop walk to my advantage at times. When getting into a tight spot for fuel, pumpout, etc. I would approach port side to, turn rudder hard to starboard, then by using forward & reverse I could walk the boat sidewise into a tight spot. Impressed some power boaters who had never seen that! Just give enough power to start moving forward, then reverse until just starting to move astern, etc. Won't work to starboard, though.
Have fun & sail fast
Bud E34 "Escapade"

 

[Seth]

Prop walk

As Bud sez, changing the prop won't help the prop walk problem. It has more to do with the offsetting of the engine installation than the prop.

To compliment his comments, the ideal way to deal is to get some momentum in reverse out in open water where you won't hit anything, then put the boat in NEUTRAL, this will stop all the prop walking completely and the boat will steer predictably. Just give it quick shots of reveerse to keep enough speed up, then go right back to neutral. When you get where you are going, use fwd. to slow or stop.

Otherwise, you will get BIG improvements in sailing performance with a folding or feathering prop, so go for it!

Happy TrailsQ

 

[Loren Beach]

Backing up is better now...

Regarding prop walk(in reverse), we really did get rid of 90% of it by going from a fixed two blade to a feathering two blade. We got info and pricing on ProWell, Max, and Martec. We went with the feathering Martec.
Note that you *will* get propwalk with both fixed and folding props. "Feathering" is a different animal entirely....

No complaints since installed in '95. Nice people to talk to when I have had any question.

Loren

 

[tilwinter]

Thanks for all the input.

Loren: about how much did the martek prop cost, and how did you set the pitch? Did the factory make a recommend?

With regard to the general comments about prop-walk, I understand that it cannot be eliminated totally, but my reading convinces me that the configuration of the prop is a relative contributer to the phenomenon.

The Varifold prop, in addition to folding flat underway, also changes it's pitch in reverse, as a feathering prop can, in such a way as to maximize the "reverse" vector relative to the "sideways" vector.

 

[Loren Beach]

feathering prop trivia

I paid about $975. direct to Martec, winter discount. Pitch is set externally on those (which was a major reason I went with that design rather than the Maxprop), so you end up looking at the pitch on the fixed prop you are replacing, and adding another degree or two, because there is no cupping in a feathering prop, and then go out and try it. Pitch, both forward and reverse, is set with external locking screws. You can see them in the picture I posted. This could be done with a quick lift just enough to swing the stern over a walk, or, by swimming under the boat with a mask and snorkel, or a hookah rig if you have one handy.
Loren