5 Bladed Props

[Simon B]

Has anyone used a 5 bladed prop for any application other than water skiing? on Steel Developments site they list towing as an application for the High 5 E series. Wondered if they were good for boats that were heavy like a dive boat. The ali 4 blader we had was an improvement, would we see any better from stainless or a stainless 5 blader?

[Turbodiesel]

I think you will find a 4 blade stainless will suit a heavy boat better. 5 blade props tend to spin up very quickly but you will loose some top end performance with them. A 4 blade is a better compromise. We have used 5 blade props on inboard diesel's to get over some of the turbo lag. But usually use a 4 blade on a heavy boat.

[jambo]

Hi yes agree with turbo on this. I had a High 5 on my 5.85 Ribcraft 150 mariner when I bhought her from a skier!! yes got up out the hole very quick. but as turbo says lost a lot at the top end also used more fuel.
I changed back down to the old reliable mariner 3 blade and I still get up reasonably but top end is better for me as I cruise the west of scotland and fuel much better. Hope this helps.
J

[Simon B]

I'm just gathering info here on what the ideal prop and operating strategy for a dive boat would be. I beleive but, am open to radical change, that what is required is;

1. A prop that gives a lot of grunt. The boat will after all be full of people and weightbelts
2. Cruise at mid range rpm (economic) not near to WOT say 15-20kts
3. Not be to mad top end, a 5.5 - 7.5m boat of divers does not need to do 35-45kts unless the helm is a nobba

I was therefore interested in the characteristics of a 5 blader, apparently they also feel smoother at cruise speeds, this is good, some divers can be ever so fussy...

[Jeff]

Have a look at a Revolution4

IMveryHO good for 'heavy' loads and works well for me > quick to plane and stays on at lower revs.... ... it is quoted as offering stern lift and it does seem to make me run nice and level. Good torque which is great for throttle response on heavier seas with even heavier divers !

Went from a 19" laser II on a 150 Optimax (RIB c 1800 kg all up) to a 17" Rev 4 and noticed a real difference. Just changed to a 175 opti and needed to move up to a 19" as too close to hitting the limiter >>>> one very tidy 17" Rev 4 for sale

Jeff

[jyasaki]

Originally Posted by Simon B

I was therefore interested in the characteristics of a 5 blader, apparently they also feel smoother at cruise speeds, this is good, some divers can be ever so fussy...

The ones who complain about the ride on my boat get invited to do beach dives from there on out...

jky

[Simon B]

Originally Posted by jyasaki

The ones who complain about the ride on my boat get invited to do beach dives from there on out...

jky

I'll put this into practice this season! Most of the complaints come from people moaning about the landing after I've taken a wave OK, so the next wave gets taken with a little more relish allowing them to make up their own minds...

[yorfuoj]

I would highly recommend a 5 blade prop, like Mercury Hifive - I didn't test other ones !

On a 510 Focchi rib + 115 Merc 2 stroke, it ran up to 49 knots with 4 on-board ... knots, not mph - and over 53 alone.
I must add that the pitch was really too high - 26" - but I had no other one available, so the rpm were really low, 4900... a bit too long to go on plane with 4 adults.
Probably a prop able to rpm up to 5500 would go faster, but around 50 knots for a 5.1m rib is not bad.

I tested another 5 blades with a 600 Prestige catamaran rib, + 150 Merc, very fast too, approximatelt 55knots if I remember well.

Smoothness, torque, speed, possible to run half-submerged ... perfect - price ...up to you

[Manos]

I have a Mercury Hi5 on my 200VMax on a 9 meter cabin RIB. The RIB weighs about 1990kgs and with 500 ltrs of fuel and 3/4 people the total weight is about 3000 kgs.
I used the boat for recreational use, mainly long distance cruising, and had tried Yamaha Saltwater series II 19, 17 and 15inch pitch props and both performed OK with the 19inch giving me more knots but not good performance in rough weather. Same with the 17 and the 15 inch pitch . But when I tried the high5/17 inch although is a slower prop and works differently (must be fully submerged, deep in the water) it outperformed the other two as in bad weather the boat will not cut speed when it hit waves and in general will motor easier than with the other props.

So all in all IMHO high five is a slower prop, but if you want power is the best.

[Andy Buoy]

Lads

I have a High Five P19 5 blade prop.
Used for 20 hours max in excellent condition.

Cheers Andy