Bruntons Varifold Propeller

[dsomers]

Just wondered if anyone has fitted a Bruntons Varifold propeller and if so their experience? I have a Thorneycroft in my Moody with a hydraulic gearbox which spins when sailing, so I am thinking of fitting one of these folding props to reduce gearbox wear.

 

[Chris_Robb]

I believe that the shaft has to be locked, or the brutton prop efectively turns in reverse when free wheeling - applying the opposite effect to what you are looking for.

I understand that they are great props, proving drive even at low revs when motor sailing. Probably the best all rounder.

 

[DickB]

They do two ranges - the folding and the feathering. The feathering prop needs the shaft locked, I suspect the folding does not. Loads of posts on the feathering variety and generally good reports. I am looking to fit one myself but the bank manager does not approve (SWMBO) for this year... Hey ho. Don't know muck about the folding version...

 

[Hunter34]

I have a Bruntons feathering prop fitted which will still turn the shaft when the boat speed exceeds 6 knots.It doesnt take much pressure to stop the shaft so I just select reverse gear.
I wouldnt say there is any extra thrust in forward like they state but makes a big difference in reverse - very responsive and reduced prop walk.
Also of course there is no longer the drag of the old 3 bladed prop when sailing.

Andrew

 

[kcrane]

As far as I know there is a Varifold (folding) and the Autoprop (feathering). My boat has the Autoprop on both saildrives (it is a cat), and as far as I can tell the claim that it provides drive when motorsailing, even if the revs are low, seems to be true.

My tests so far have been simple and limited, but on a run in a lightish wind we were doing 4knts under sail alone. With the engines on ahead, but at low revs (but above tickover) we went up to 5knts. Back to 4knts when engines off and locked in gear. Under power alone at the same revs, I doubt the boat would be doing 4knts, never mind 5knts, but I didn't try it.

The idea is that the props rotate until the pitch is coarse enough for them to get a bite on the water. If the water is flowing past the prop already (sailing at 4knts) they pitch up until they are coarse enough to add to the thrust. This also has the effect of loading the engine and using its torque, which I understand is good for diesels.

Just my experience so far.

 

[jh001ace]

I fitted a Varifold on my Beneteau 331 at the start of this season, I've found it to be very good. I was expecting poor astern performance but was pleasently surprised by the results of my first test run.

When undersail the shaft will rotate if astern is not engaged, overall VERY pleased with the prop.

 

[castaway]

Hi Dave

PBO did a report on all the main contenders in the feathering/folding market either last month or the month before.

I must say I would love to have one, and rather fancy the Kiwi Prop, Im though a bit worried about the amount of wear some users report on these props generaly. Expensive bit of kit and not the sort of thing you want to be replacing every 5 years or so.

Regds Nick

 

[charles_reed]

I\'ve had an Autoprop

from the 2nd year of production (1990).
It certainly offers far better results when motor-sailing, less drag when sailing, better bite in reverse (after the subjectively inteminable delay when first engaging reverse) but very little improvement to still water top speed over a properly tuned 3-bladed propellor.

However you can still get max power revs when fighting a F8, impossible with the same prop.