This is not a new topic about Axiom Propellers. (honest)

[Picard]

Hi. Been looking at Axiom propellers for a while, most of the reviews seem to be in favor of them, not getting one at mo, but when my prop drops into the cut, or I lose a blade, or my numbers come up on the Lottery, Axiom it is. Then this comes up. "Powerstop", www.propellersolutions.co.uk, seen in Canal World, says 50% more stopping power, less prop walk, more control in reverse. Has any one got one? seen one? or any views? Many thanks. PS. no connection.

[WotEver]

They look like high-revolution outboard props to me, not for displacement vessels (unless I didn't look hard enough).

 

Tony

 

Oh... I didn't look hard enough

 

http://www.propellersolutions.co.uk/powerstop.htm

[Tiny]

They seem to cost a lot. The prop that interested me was that one that stops boats quick and costs little more than a normal prop.

[Phoenix_V]

They seem to cost a lot. The prop that interested me was that one that stops boats quick and costs little more than a normal prop.

 

They seem a lot cheaper than the Axiom on the prices quoted in the magazine, dont forget you are paying about 30% more for a better quality alloy.

 

On the other hand I emailed them 3 days ago for a quote, no reply to date.

[John C]

Is there anywhere that gives unbiased reasoning as to why these propellers are better than a conventional prop?

 

My (limited) understanding of prop theory tells me that a prop is more efficient in one direction than the other, on a boat the "efficient" direction is forward. So, to improve stopping by running the prop in reverse, the "inefficient" direction, then perhaps the design is a compromise, much as it is with a bow thruster. It is also said that "prop walk" is also reduced, this would suggest a less efficient prop in the forward direction.

 

It is also claimed that there is less wash, presumably from the prop not the hull, could this be because it is shifting less water due to lower efficiency?

[steelaway]

Is there anywhere that gives unbiased reasoning as to why these propellers are better than a conventional prop?

 

My (limited) understanding of prop theory tells me that a prop is more efficient in one direction than the other, on a boat the "efficient" direction is forward. So, to improve stopping by running the prop in reverse, the "inefficient" direction, then perhaps the design is a compromise, much as it is with a bow thruster. It is also said that "prop walk" is also reduced, this would suggest a less efficient prop in the forward direction.

 

It is also claimed that there is less wash, presumably from the prop not the hull, could this be because it is shifting less water due to lower efficiency?

 

 

 

 

Eggsackerly!!!

 

Alex

[PhilR]

Is there anywhere that gives unbiased reasoning as to why these propellers are better than a conventional prop?

 

My (limited) understanding of prop theory tells me that a prop is more efficient in one direction than the other, on a boat the "efficient" direction is forward. So, to improve stopping by running the prop in reverse, the "inefficient" direction, then perhaps the design is a compromise, much as it is with a bow thruster. It is also said that "prop walk" is also reduced, this would suggest a less efficient prop in the forward direction.

 

It is also claimed that there is less wash, presumably from the prop not the hull, could this be because it is shifting less water due to lower efficiency?

 

All good points which I agree with. It will be interesting to hear what Middlewich Narrowboats have to say .............

[Biggles]

Why is there this want to stop quickly?

 

If you are keeping a good watch, at the speeds we travel emergency stops should never be required.

 

I'd rather have a prop that works well going forward. The laws of physics says you can't have it both ways!

 

How many prop planes have a reverse gear?................. OK I know some variable pitch props have beta mode.

 

Biggles

[Tiny]

Why is there this want to stop quickly?

 

If you are keeping a good watch, at the speeds we travel emergency stops should never be required.

 

I'd rather have a prop that works well going forward. The laws of physics says you can't have it both ways!

 

How many prop planes have a reverse gear?................. OK I know some variable pitch props have beta mode.

 

Biggles

 

Given the number who panic, slam the boat into reverse and slew down the waterway out of control anything to make them stop quicker might be an excellent safety feature. It is amazing how mony come round a corner in such a position that it's difficult to avoid them if they do the right thing let alone trying to avoid them when they slam it into reverse. As for damage to lock gates a better stopping prop might reduce this.

[Proper Job]

All good points which I agree with. It will be interesting to hear what Middlewich Narrowboats have to say .............

I think if I were a hire fleet owner, a propeller that gave better stopping performance with a slight reduction in efficiency when going forward, would be a good thing.

 

[ditchcrawler]

I think if I were a hire fleet owner, a propeller that gave better stopping performance with a slight reduction in efficiency when going forward, would be a good thing.

 

I think you are right

[Nine of Hearts]

Why is there this want to stop quickly?

 

Don't know about yours, but my boat doesn't steer too well in reverse. So if I'm manoeuvering in a tight spot, winding, or making the right turn out of the bridge hole from my mooring, I turn in forward until I run out of room, then reverse. She's only actually swinging around when under forward power, quite often when backing some of the turn comes off. So if I could spend longer going forwards and turning, knowing I could stop her on a sixpence, that would be really handy.

 

This isn't a case of allowing you to cane it round the network, which narrowboats don't do, it's about increasing manoeuverability, and narrowboats do a lot of manoeuvering. Mine does, anyway. (as a proportion of it's journeys, before any of you cheeky whipper-snappers pipe up)

[John C]

I think if I were a hire fleet owner, a propeller that gave better stopping performance with a slight reduction in efficiency when going forward, would be a good thing.

 

I think if I were a hire fleet owner, a propeller that made me spend more money on fuel would soon be changed!

[Proper Job]

I think if I were a hire fleet owner, a propeller that made me spend more money on fuel would soon be changed!

I think the amount of money spent on fuel would have very little to do with the type of propeller, more to do with the driving style of the hirer.