Prop

StephenS

New Member
Hi. I'm a new member. I have a 2 blade folding prop on my E32-3. I'm thinking of a 3 blade Max feathering prop. Does anyone have an opinion or suggestion?
Thanks
 

Loren Beach

O34 - Portland, OR
Senior Moderator
Blogs Author
Welcome to the Ericson site!
If you can afford a featherer, I say go for it. Especially the three blade. I had a Martec AutoStream two blade on our boat for ten years and while we were faster under sail, we lacked speed under power. I changed to a 3 blade fixed and our speed moved up to 7.0 when motoring, about a half knot improvement. This costs us a half knot of speed under sail , so yup it's a compromise. :)

There are several brands/vendors for feathering props, so find one that has good support in your geographic area. The new Max Prop with external pitch adjustment looks pretty good, FWIW.

Let us know what you decide.
 

Dave G.

1984 EY30+ Ludington, MI
Welcome Stephen !
I would look at the Flexofold props too. There are 2 boats at my YC that installed 3 blade versions last season and they both rave about them. One is on a C&C 37 and the other boat is a Frers 41. Obviously they are folding props but the geared type so much more responsive. I was hoping to get a 2 blade this year but the budget is busted already I'm afraid. The 3 blade versions are about $2,400+, the 2 blade is about half that amount.
 

StephenS

New Member
Thank you for the welcome gentlemen.

Loren what 3 blade prop did you purchase?

My boat is an E32-3, 1985. what size prop do you fellows suggest?
 

Dave G.

1984 EY30+ Ludington, MI
As far as prop sizing, whoever you decide to go with should have a "scientific" specification to meet your boats criteria. That being said unless they're local and actually look at your boat you will have to make sure what they suggest will actually fit. Hull clearance, rudder clearance(especially if it's a folder). Size and pitch are also critical in regards to engine load and RPMs. Is your boat out of the water or do you know what size/pitch prop you currently have ? I know I got a couple of quotes for props and after giving them all the boat particulars they asked for I received quotes for 14" & 15" props. Problem is I currently have a 13" 2 blade and only have about an inch of hull clearance now so clearly those will not work. That brings us back to the "scientific" part, science doesn't always work so then the "black art" of prop sizing begins.
 

nquigley

Sustaining Member
When my, then-16, son proposed shortening the length of the exhaust pipe on the aging Volvo 240 we bought him as a first car (his friend said it would 'perform' better - we all know what a performance beast the 240 is ...), I asked him if he wondered why those highly educated Swedish engineers decided to make it the length they did. I wonder if the same logic applies to my (OEM?) fixed 2-blade prop: surely knowledgeable engineers at Ericson put a good amount of thought into matching the prop with the engine and transmission before telling the yard what prop to slap on her as she left the shed. If I was using her for competitive racing, I might think about a folding prop for drag reduction, but I doubt I'll get significantly better motoring speed, mpg, engine longevity, etc., by trading up to a more sophisticated prop when mine is still in perfect 'shape'.
 

Frank Langer

1984 Ericson 30+, Nanaimo, BC
Dave,
I also got a recommendation for a 15 x 9 from Varifold, maker of the 2 blade folding prop the previous owner installed. I have a 13 x 9, for the same reason you mentioned, it's the largest possible without hitting the rudder.
I'm sure it saves me about a half knot when sailing due to folding. I can reach 6.2 knots motoring in calm waters at 2200 rpms, but its a bit more challenging in choppy waves, where I struggle to reach 5 knots. Once I get going on reverse it's fine, but I do get initial port prop walk even with a burst of throttle.
Frank
 

Loren Beach

O34 - Portland, OR
Senior Moderator
Blogs Author
Thank you for the welcome gentlemen.

Loren what 3 blade prop did you purchase?

My boat is an E32-3, 1985. what size prop do you fellows suggest?
I have a narrow blade design, a Michigan 'sailor' prop. Supposedly less drag under sail. The overall blade area is visibly less than it would have in a conventional three blade, for sure.

One caveat -- when my prop was new, it was checked by a local shop for true-ness to spec, and found that two of the three blades were off on their pitch by a half inch. I had to pay to have it re-pitched, which irked me.
I would use another brand if there were a next time.
 

Dave G.

1984 EY30+ Ludington, MI
If your a diehard racer then get all the sail speed you can and a prop makes a difference for sure. Most club racing around here is by PHRF ratings and you do get an allowance for fixed props so not as critical in those events anyway. Just looked at my PHRF cert and you get 6s for a 2 blade fixed prop, doesn't seem like enough if you gain half a knot with a folder but didn't do the math either.
 

StephenS

New Member
Thanks for the input everyone. PYI, suggested a 15"x9" max prop. I'm going to wait for hauling my boat in October, and make sure i can get the right size.

Steve
85 E32-3
Rapunzel, Marina del Rey CA
 

Geoff W.

Makes Up For It With Enthusiasm
Blogs Author
I got a max prop easy 3 blade 15" on my 32-3 and pitched it to 9". Reverse thrust is really nice now, but I have to say my forward thrust isn't quite what I was hoping from a 3 blade. I have a feeling my engine may be losing power, or maybe it wants to be pitched one bolt higher than what I've got.
 

TimTimmeh

Member II
I'm considering replacing my 2 blade fixed on my 34, I'm considering the flexofold supposedly has good power ahead and great sailing performance, I'm not to worried about reversing.
 

debonAir

Member III
I put on a flexofold last year. It reverses (and forwards) better than the 2-blade fixed it replaced. Less prop walk, and more power.
 
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