Ray Hughes
Member I
I will be hauling my 1971 E-29 soon for bottom paint re-coat. I'd like to replace the prop (A-4 engine)-- to minimize reverse prop walk. Any ideas or recommendations? Thanks, Ray Hughes "Capricious" Oceanside Harbor, CA.
Prop replacement for E-29 (A-4)
- Thread starter Ray Hughes
- Start date
Joe Benedict
Member II
User Updates Needed
Ray, I will be replacing the prop on my '77 E29 this winter also. According to other postings on this site there are at least 3 props available at http://www.atomic4.com (this is the Indigo prop) http://www.sailcdi.com/ppmain.htm, and the Campbell Sailor Propellor which I have been unable to find the manufacturer's website. Unfortunately, several of the threads end with people saying they are going to try a prop - with no subsequent follow up - WE NEED UPDATES! I agree the original prop creates a lot of prop walk. While this is not a real problem approaching an open mooring, it's a real thriller when getting in and out of a slip.
Ray, I will be replacing the prop on my '77 E29 this winter also. According to other postings on this site there are at least 3 props available at http://www.atomic4.com (this is the Indigo prop) http://www.sailcdi.com/ppmain.htm, and the Campbell Sailor Propellor which I have been unable to find the manufacturer's website. Unfortunately, several of the threads end with people saying they are going to try a prop - with no subsequent follow up - WE NEED UPDATES! I agree the original prop creates a lot of prop walk. While this is not a real problem approaching an open mooring, it's a real thriller when getting in and out of a slip.
Here ya go. Found it on Google.
http://www.vicprop.com/sailor.htm
I read all their splash page information, and note that this prop will do everything except cure cancer and baldness.....
It is a fixed three blade prop with narrower blades. It should produce a smidge less drag under sail than the props with more blade area. Beyond that, their claims seem a bit, um, "enthusiastic." The reduced blade area is probably why they reccommend a three-blade over a two. After all, it is total blade area, along with blade shape, that really determines thrust.
As to reverse power and prop walk, I believe that you will find that only a feathering prop will (mostly) cure these ailments.
As in so many things in life, it all hinges on price... I admit that I could have purchased a couple of two blade fixed props for what I paid for my featherer, but then I never claimed that boat upgrades were logical uses of money... And, in our marina, solid straight-line backup power is a huge help.
If you decide to try one, check with the used parts chandleries, as well.
This is the kind of item that someone might buy and try and then change their mind and re-sell, based on their own empirical data.
Best,
Loren in PDX
http://www.vicprop.com/sailor.htm
I read all their splash page information, and note that this prop will do everything except cure cancer and baldness.....
It is a fixed three blade prop with narrower blades. It should produce a smidge less drag under sail than the props with more blade area. Beyond that, their claims seem a bit, um, "enthusiastic." The reduced blade area is probably why they reccommend a three-blade over a two. After all, it is total blade area, along with blade shape, that really determines thrust.
As to reverse power and prop walk, I believe that you will find that only a feathering prop will (mostly) cure these ailments.
As in so many things in life, it all hinges on price... I admit that I could have purchased a couple of two blade fixed props for what I paid for my featherer, but then I never claimed that boat upgrades were logical uses of money... And, in our marina, solid straight-line backup power is a huge help.
If you decide to try one, check with the used parts chandleries, as well.
This is the kind of item that someone might buy and try and then change their mind and re-sell, based on their own empirical data.
Best,
Loren in PDX
Joe Benedict
Member II
Loren, You're correct the Victoria product appears to be a wonder product. I sent an inquiry to a thread under the Design section to someone who had installed a CDI product. As for the technical aspects, I got in a very long discussion with a few nautical engineers at a chilli cook off at the mariner last summer. (Note to self mix margaritas before hand else one starts drinking just the tequilla after a while.) There are many opinions regarding 2 or 3 blades, pitch, variable pitch, folding etc. Most of us aren't loosing a race by a boat length - so the extra drag from 3 blades shouldn't be a big problem. (I heard one theory that since the prop is designed to go through water there is no increase in drag.) Also, on an E29 there is a clearance issue with the folding prop. In the end the one thing that does make sense is that the shape of the blade is critical as to how it slices through the water. However, unlike other designs, CDI's blades are symetrical so it cuts through the water the same in forward or reverse. Any thoughts? After we solve this mystery maybe we should tackle the meaning of life - oops Monty Python already handled that.
Blade "shape" is important to efficiency for a prop. That's the one drawback I see with featherers -- no cupping. In order to "feather," they appear to be symetrical from surface to surface. This is true of Martec and Maxprop, in all the examples I have seen.
Note: do not let the discussion accidently wander into "folding props"... some readers may confuse the trademark with the type of technology.
Strictly FWIW, off the three basic choices, I observe the folders to be the worst at reverse power by far.:eek:
Since the feathering props always have their leading edges going into the water flow for the direction of choice, they should always have the thrust advantage in either direction. Works that way for my Martec "Autostream" two blade featherer, anyway.
As mentioned before, there is a picture of my prop elsewhere on this site --search on "prop options" for a picture.
Loren in PDX
Note: do not let the discussion accidently wander into "folding props"... some readers may confuse the trademark with the type of technology.
Strictly FWIW, off the three basic choices, I observe the folders to be the worst at reverse power by far.:eek:
Since the feathering props always have their leading edges going into the water flow for the direction of choice, they should always have the thrust advantage in either direction. Works that way for my Martec "Autostream" two blade featherer, anyway.
As mentioned before, there is a picture of my prop elsewhere on this site --search on "prop options" for a picture.
Loren in PDX