Axiom propellers

[Neil Smith]

Hi all,

 

I am thinking about buying an axiom prop for my new 58 foot narrowboat, has anyone got one and are they worth nearly double a normal prop.

 

Neil

[MtB]

A ton of stuff already said here on the subject...

 

For example:

 

http://www.canalworld.net/forums/index.php?showtopic=22942&hl=axiom

 

And

 

http://www.canalworld.net/forums/index.php?showtopic=29276&hl=axiom

 

 

 

MtB

[frangar]

Talk to crowthers....proper props!

 

http://www.crowthermarine.co.uk

 

Cheers

 

Gareth

[David Mack]

 

Or

 

[Bee]

Dunno, but if you swap and have an 18 x 13 RH blade going spare I could take it off your hands. My 16 x ? RH is a bit small

[peterboat]

In the science museum in London their is a whole section on propellers I wandered around it for over an hour it was all very good stuff their were props there that looked just like axioms the basic blurb was that prop technology hadnt advanced much in the last 100 years and wasnt likely too

 

Peter

[nicknorman]

Hi all,

 

I am thinking about buying an axiom prop for my new 58 foot narrowboat, has anyone got one and are they worth nearly double a normal prop.

 

Neil

No, but my feeling is no.

 

Having a good (including "good" as in well matched to the boat and engine) prop makes a big difference but axiom doesn't have a monopoly for that. As suggested I would be more inclined to trust a Crowther.

[MtB]

It's Axiom's complete failure to produce any evidence to support their marketing claims that leads to all the debate.

 

(In case you hadn't noticed this.)

 

 

 

MtB

[nicknorman]

It's Axiom's complete failure to produce any evidence to support their marketing claims that leads to all the debate.

 

(In case you hadn't noticed this.)

 

 

MtB

Plus some reports from folk who have them. They are not dreadful, just not worth the premium price.

[Drayke]

I know a couple that had a 70 x 12 wide beam, crap boat to stop even when going very slow until they fitted an Axiom prop so for them the extra cost was worth it.

Fred.

[Tony Brooks]

It's Axiom's complete failure to produce any evidence to support their marketing claims that leads to all the debate.

 

(In case you hadn't noticed this.)

 

 

 

MtB

 

I think they did produce a report about "draw bar pull" that was in their favour , but not much about other claims.

[nicknorman]

I know a couple that had a 70 x 12 wide beam, crap boat to stop even when going very slow until they fitted an Axiom prop so for them the extra cost was worth it.

Fred.

But the unanswered question is whether fitting a correctly sized quality conventional prop would have had much the same effect.

[robmilton]

I fitted one 18 months ago and am very pleased with it, very little prop wash with it and it stops on a button ! Doesn't seem to foul much either. Was worth the money to me.

[trackman]

Our boat has a correctly matched conventional prop fitted by the builder. He knows his stuff, probably got the prop from a well known chandler in the midlands, not even from Crowthers.

The boat stops on a button, goes like the proverbial train. Paying double normal price isn't necessary.

If you don't know how to size your prop ask Crowthers.

[Neil Smith]

Just given all my details to crowthers to see what they recommend, will let you know what and the cost.

 

Neil

[Dalslandia]

As an Propeller expert, (airplane) and ship Captain, I would say that the axiom propeller look like it will be equally good for propulsion and stopping, meaning not specially good on either. and not very efficient if looking at planform or twist, nor airfoil, but for a propeller that need to be good at both ways, for low speed where efficiency isn't good anyway, or why not as a propeller for a bow thruster, I think it will be very good.

But as an good matched propeller it will be better then any bad matched propeller of any brand.

 

www.dalslandia.com

www.jcpropellerdesign.com

[Neil Smith]

After speaking to crowthers I can get the axiom for about the same price so will try it and see how good they really are.

 

Neil

[MtB]

How will you know which is best?

 

MtB

[bottle]

That's easy, whichever one he buys will be the best.

[MtB]

Ah yes. Anyone shelling out £500 on a new blade will need to believe they haven't been had over

 

 

MtB

[Dalslandia]

You need to buy two different props so we other suckers on the forum will know :-)

[cereal tiller]

As an Propeller expert, (airplane) and ship Captain, I would say that the axiom propeller look like it will be equally good for propulsion and stopping, meaning not specially good on either. and not very efficient if looking at planform or twist, nor airfoil, but for a propeller that need to be good at both ways, for low speed where efficiency isn't good anyway, or why not as a propeller for a bow thruster, I think it will be very good.

But as an good matched propeller it will be better then any bad matched propeller of any brand.

 

www.dalslandia.com

www.jcpropellerdesign.com

IIRC the company that made "the King's new clothes" used a propeller as a Logo?

 

CT

[Neil Smith]

The crowther one and the axiom are about the same price so how are we being had over, and if as is claimed stopping distance and reversing is improved it cant be all bad, but no I cant compare as its a new boat, but technology gets better all the time so why not with props.

 

Neil

[RLWP]

The crowther one and the axiom are about the same price so how are we being had over, and if as is claimed stopping distance and reversing is improved it cant be all bad, but no I cant compare as its a new boat, but technology gets better all the time so why not with props.

 

Neil

 

Because the physics doesn't change. And props are an old technology which has been very well explored for over a century. In fact, some of the very first props looked very like an Axiom

 

So, Crowthers price for a correctly calculated prop with good customer support is the same as an off the peg Axiom?

 

Richard

[MtB]

The crowther one and the axiom are about the same price so how are we being had over, and if as is claimed stopping distance and reversing is improved it cant be all bad, but no I cant compare as its a new boat, but technology gets better all the time so why not with props.

 

Neil

 

Well as Daslandia pointed out, improved stopping is at the expense of reduced forward efficiency.

 

Is that ok with you?

 

 

MtB