# Advantages of SS Props



## Vertigo (Jun 3, 2012)

The main advantage in my area is that I can run a SS prop thru an oyster bed and it won't get dinged. Of course, if you hit a rock, an aluminum prop may save your lower unit.


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## WhiteDog70810 (May 6, 2008)

I am with Vertigo. In abrasive/"little" hit environments, SS is far superior. We hit oysters, stumps, crab traps and other soft-ish stuff entirely too frequently with the same factory Yamaha SS prop from the time of purchase in '88 and until my dad sold that boat/motor in '12 and it was still going strong. In "big" hit environments like rocky rivers, an aluminum prop will fracture before there is damage to the motor. Guys that run rocky rivers talk about carrying a couple of extra props and have a prop shop on speed-dial to repair the casualties.

Aluminum is more rigid and lighter, so it probably has benefits when speed is the priority. However, I bet most fishermen can't really tell the difference since most fishing hulls are "geared down" at the prop to handle the higher end of the predicted load range.

Nate


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## MariettaMike (Jun 14, 2012)

Islander said:


> Hey all. I was running a 4 blade SS prop but decided that I would rather sacrifice a little bit of hole shot for a bit more speed. Are there any advantages other than strength-durability on running ss opposed to aluminum? Went back to my stock aluminum 3 blade.


SS blades will bend where aluminum blades will break, however SS blades can also bend prop shafts.

You can stall your engine when hitting rocks with SS at idle speeds without causing any noticeable damage, but the aluminum blades will bend and/or break. (The rubber hubs are the same.)

Although I don't think that matters so much when you've still got the whole skeg on your lower unit because it hits first and kinda protects the prop. But after you've shortened your skeg by running in sand or hitting rocks then the blades are the first thing to hit.

I think the people that put those SS covers on their lower units are creating more risk of severely damaging their engine and transom than the reward of not breaking the skeg.


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## Vertigo (Jun 3, 2012)

One more advantage of SS is that a good prop shop can modify pitch and cup for fine tune. Aluminum is what it is.


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## Islander (Sep 16, 2012)

MariettaMike said:


> SS blades will bend where aluminum blades will break, however SS blades can also bend prop shafts.
> 
> You can stall your engine when hitting rocks with SS at idle speeds without causing any noticeable damage, but the aluminum blades will bend and/or break. (The rubber hubs are the same.)
> 
> ...


That would be the strength/durability that I mentioned. What I'm interested in are performance differences. Will a ss prop give the same Rpms as an alum of same pitch? Someone recently told me that due to strength, SS blades are thinner than alum allowing them to spin a little quicker, resulting in a little higher rpms. I'm running a 14p alum, not quite getting 5500, thinking maybe a 13 might be what I want. Input much appreciated !


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## Vertigo (Jun 3, 2012)

First off, not all props stamped 14 pitch are exactly 14 pitch. Different brands and types will perform differently. There's really no sure way to tell how a prop will perform in your application until you test it on the water. If you go from a 14 pitch aluminum to a 13 pitch aluminum of the same model from the same manufacturer, chances are you'll see the appropriate rpm increase. But, if you go from 14 pitch aluminum to 13 pitch steel and go from different models and makers in the bargain, there's no telling what results you're liable to get.

Best way to get precisely what you want is to order a stainless prop from someone like Ken at Prop Gods http://www.propgods.com/Content2/Default.aspx then you can swap out as necessary, or even go to a good prop shop and have the prop tweaked for the last bit of performance.


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## RunningOnEmpty (Jun 20, 2015)

MariettaMike said:


> SS blades will bend where aluminum blades will break, however SS blades can also bend prop shafts.
> 
> You can stall your engine when hitting rocks with SS at idle speeds without causing any noticeable damage, but the aluminum blades will bend and/or break. (The rubber hubs are the same.)
> 
> ...


Your 100% correct about a short worn skeg combined with a stainless prop! Unfortunately I bent my prop shaft and took out my crank shaft. Thankfully it was insured well.


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## "Scott" (Apr 10, 2015)

Hi Islander, I was always of the belief that SS props offered better performance compared to the same in aluminium due to less flex and loss of efficiency. I usually keep the original aluminium prop that comes with the motor in the boat as a spare, but upgrade to a stainless steel prop at the earliest opportunity once I have sorted out the usual running weight, etc.

Check out the following.... Plenty of info out there.... And when you look at performance boats, they all almost exclusively run stainless steel props...

http://www.boats.com/how-to/which-is-best-aluminum-or-stainless-steel-boat-propeller/

Regards
Scott


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## "Scott" (Apr 10, 2015)

Islander said:


> That would be the strength/durability that I mentioned. What I'm interested in are performance differences. Will a ss prop give the same Rpms as an alum of same pitch? Someone recently told me that due to strength, SS blades are thinner than alum allowing them to spin a little quicker, resulting in a little higher rpms. I'm running a 14p alum, not quite getting 5500, thinking maybe a 13 might be what I want. Input much appreciated !



Not sure about the spinning quicker.... But certainly more efficient.... Less flex of the blades, therefore less loss of force, etc. 
Regards 
Scott


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## KnotHome (Jul 21, 2009)

Yes, ss spins faster because it's thinner. Where are you located? I know there's a place in Tampa that has props you can test (for a price of course). I'll see if I can find their #. Your prop might not be the only thing holding back your rpms though; it could be the motor itself.


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## CurtisWright (May 9, 2012)

I routinely switch between my 4 blade stainless and my 3 blade stock prop. I use my 4 blade when I am going to be in the marsh and need to be able to run skinny, turn sharp, and hit oysters. I run my three blade when I am going up the river or running the beach and need the extra speed. I always keep the one I am not using in my boat in case I spin the hub or hit something hard.

The main difference I noticed between the SS and the aluminum is that the SS props are usually cupped and add alot more torque to the tiller arm. The aluminum prop adds almost none and gives me an extra 4mph


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## Islander (Sep 16, 2012)

Thanks guys, all good info!


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