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View Full Version : "CLEVER" vs. "CLEAVER"



gcarter
02-18-2008, 06:17 PM
The word "CLEVER" has been used a number of times in reference to propellor.........I couldn't quite get the connection, so I dug out my old dictionary......you know, the kind printed on paper:eek!:

So here we go;
CLEVER, adj. 1. Having a quick mind, bright, intelligent, "She is the cleverest person in our family".
2. Skillful in doing some particular thing, " He is a clever carpenter".

Well, I never knew of a propellor that was sentient, although I had a friend once who was always talking about "Mr Pencil" or whatever else he had in his hand. So I then looked up "CLEAVER";
CLEAVER, n. A cutting tool with a heavy blade and a short handle, a butcher uses a cleaver to cut through bone.

Well OK! I've seen propellors with blades that looked like a certain cutting tool. The only difference is a butchers cleaver has a sharp leading edge, while a cleaver propellor has a very blunt thick trailing edge. The whole idea in the design was to eliminate material on the blades where cavitation might occur at high speeds. But what works well at high speed might not work so well at low speeds, so a cleaver prop might blow out easily at low speeds. While very popular in the '80's, propellor design (maybe even clever propellor design) has advanced tremendously in the last 25 years and it's now possible to have an overall better performing propellor with more of a round ear. Still lots of old cleavers running around....I even have one stored in a corner of the shop. I wouldn't let anyone use it though.

BlownCrewCab
02-18-2008, 06:40 PM
I Say: Mr Carter is "Clever" for keeping that "Cleaver" Hidden in the corner of his garage and not letting his friends use it..

mjw930
02-18-2008, 06:45 PM
Mercury uses the Cleaver spelling and in the past used the
®

Symbol indicating they registered that a unique to them. They still do that with the Chopper props but no longer do it with the Cleavers for the #6 and SSM props. I suspect there was a challenge and they either lost or decided not to fight it.

I'm quite surprised at the performance of a 23" Cleaver on my 22. I don't get any blowout and it is running around 10% slip across the board. What it can't do is carry the bow above 60 mph so I get porpoising if I try to run positive trim.

I can see where they get the name with the sharp leading edge and the thick top but the profile is more like a butcher knife than a cleaver. I suppose they didn't think the Mercury Butcher Prop would be as catchy a name :propeller:

Carl C
02-18-2008, 06:50 PM
You made me pull out my really thick Webster's and a cleaver can also mean someone who cleaves. But anyway if cleavers are outdated then why is Mercury Racing advertising the crap out of their new CNC machined cleavers? They are said to "maximize hull performance".:propeller:

gcarter
02-18-2008, 07:11 PM
You made me pull out my really thick Webster's and a cleaver can also mean someone who cleaves. But anyway if cleavers are outdated then why is Mercury Racing advertising the crap out of their new CNC machined cleavers? They are said to "maximize hull performance".:propeller:
I speak only in generalities........exceptions exist everywhere.
And if you think there are a lot of variations in performance boat propellors, just look at submarine props, or some of the latest composite aircraft props.
As far as defininition #2 goes, I couldn't think of a healthy example to use.

My old Merc cleaver that came stock on the Minx would blow out badly at low speeds. Also a lot of slip everywhere.

I borrowed a labbed 25" cleaver to try from a fellow board member. It had some very quirky handling characteristics. But it ran the fastest speed ever in that boat. I was very glad to be w/o it.

Carl C
02-18-2008, 08:19 PM
I think they're for the bigger boats, I know I wouldn't want one on my 22C.

mjw930
02-18-2008, 09:18 PM
I think they're for the bigger boats, I know I wouldn't want one on my 22C.

Ya never know until you try...... I thought the same thing and was totally stunned when the boat performed the way it has.

I've got a Turbo on it's way and I'm trying find some smaller 4 blade "semi" Cleaver props like the Hydromotive and Revolution 4 to try as well. Testing is the only way to know for sure.

Tidbart
02-19-2008, 10:50 AM
George,

If you started the thread, "Did you ever notice how some people use the words cleaver and clever interchangibly?" I'd say you were bucking to replace Andy Rooney.:wink:

B

gcarter
02-19-2008, 06:41 PM
George,
If you started the thread, "Did you ever notice how some people use the words cleaver and clever interchangibly?" I'd say you were bucking to replace Andy Rooney.:wink:
B
:propeller::propeller::):cool: