spurs v stripper

[boatmike]

As usual its always worth posting on here to get the advantage of the folorum's collective experience. I suppose there has to be a limitation in any design and if you are unfortunate and hit say a steel cable I would think it preferable to lose a component of the stripper than rip a P bracket out of its seating but I am interested to hear how often it seems to have happened. Is this something that Sadlers are particularly prone to? Someone suggested Moodys have a more substantial P bracket?? Anyone with a Moody ever had a similar train wreck??

 

[boatmike]

I have a Featherstream prop and when I spoke to Darglow recently about some new anodes they told me that they now produce their own version of the Stripper, called the HydroAxe. Looks very similar. I have a Stripper and am happy with it.

Yes indeed they do but up to this point they have only done a saildrive version

 

[Poey50]

As usual its always worth posting on here to get the advantage of the folorum's collective experience. I suppose there has to be a limitation in any design and if you are unfortunate and hit say a steel cable I would think it preferable to lose a component of the stripper than rip a P bracket out of its seating but I am interested to hear how often it seems to have happened. Is this something that Sadlers are particularly prone to? Someone suggested Moodys have a more substantial P bracket?? Anyone with a Moody ever had a similar train wreck??

I know of at least four incidents on Sadlers of the Ambassador holding bracket ripping out of the P-bracket. Since raising the question on a Sadler group I've also heard three reports of the Ambassador surviving some substantial hits without damage. One person whose bracket survived had embedded it in epoxy-metal in addition to the usual fixings so I'll do the same on the basis that it can do no harm.

 

[Tranona]

As usual its always worth posting on here to get the advantage of the folorum's collective experience. I suppose there has to be a limitation in any design and if you are unfortunate and hit say a steel cable I would think it preferable to lose a component of the stripper than rip a P bracket out of its seating but I am interested to hear how often it seems to have happened. Is this something that Sadlers are particularly prone to? Someone suggested Moodys have a more substantial P bracket?? Anyone with a Moody ever had a similar train wreck??

The block attachment is the safety valve - that is it is the first thing likely to fail if the rope/net plastic etc overwhelms the prop and drive and the engine is still going hard. However in reality with smaller hp engines the engine stalls first. The thing with getting stuff round the prop is that it is so variable. Probably the worst is when a polyester rope gets into the gap between the prop and the P bracket and winds its way in, often melting as it goes. This can pull engines off mounts or even (particularly with one type of engine where the mounts are on an aluminium casting) pull the mounts off the engine. Damage to the P bracket is rare - the issue as described here is on thin wall tapered housings where you can only get 2 or 3 threads in the aft screw unless as suggested you go into the cutless shell. Most p brackets and cutless housings are much more substantial with plenty of depth for the threads. Also boats like the Moody have really strong attachment for the bracket. The really vulnerable P brackets are on twin crew motor boats where the combination of lots of power and often (on older boats) rather lightweight P brackets - get a rope caught by both props and you can imagine what happens. Brings a whole new meaning to the term Spanish windlass.

On the positive side, you will see as in this thread plenty of accounts of cutting spinnaker sheets, mooring warps, punching holes through nets, shredding fertilizer sacks and so on. Often the only way you know is a drop in revs or a stream of debris in the prop wash.

 

[john_morris_uk]

Dunno about weak P brackets as we have an Ambassador Stripper and we’ve never had any problems. I know it works because the day after I’d fitted it and re-launched the boat I reversed over one of our oversize mooring lines on the trot mooring we were using at the time and neatly chopped straight through it. That was a tad embarrassing.

 

[boatmike]

The block attachment is the safety valve - that is it is the first thing likely to fail if the rope/net plastic etc overwhelms the prop and drive and the engine is still going hard. However in reality with smaller hp engines the engine stalls first. The thing with getting stuff round the prop is that it is so variable. Probably the worst is when a polyester rope gets into the gap between the prop and the P bracket and winds its way in, often melting as it goes. This can pull engines off mounts or even (particularly with one type of engine where the mounts are on an aluminium casting) pull the mounts off the engine. Damage to the P bracket is rare - the issue as described here is on thin wall tapered housings where you can only get 2 or 3 threads in the aft screw unless as suggested you go into the cutless shell. Most p brackets and cutless housings are much more substantial with plenty of depth for the threads. Also boats like the Moody have really strong attachment for the bracket. The really vulnerable P brackets are on twin crew motor boats where the combination of lots of power and often (on older boats) rather lightweight P brackets - get a rope caught by both props and you can imagine what happens. Brings a whole new meaning to the term Spanish windlass.

On the positive side, you will see as in this thread plenty of accounts of cutting spinnaker sheets, mooring warps, punching holes through nets, shredding fertilizer sacks and so on. Often the only way you know is a drop in revs or a stream of debris in the prop wash.

Agree Mr T. If the gismo does its job properly you may never know its happened. I was a little concerned at first with the number of failures reported, but it seems the good old Moody has a bit more meat around the P bracket so should be OK. Thanks to everyone for the useful input .

 

[Bobc]

Stripper every time. Spurs are rubbish, even with Harry Kane.

 

[Pete7]

Agree Mr T. If the gismo does its job properly you may never know its happened. I was a little concerned at first with the number of failures reported, but it seems the good old Moody has a bit more meat around the P bracket so should be OK. Thanks to everyone for the useful input .

Ran over a 16mm mooring line whilst in gear at tickover. Engine stalled. By chance we were feet away from a travel lift. Lifted and 5 minutes of violence with a carving knife had the rope removed and us going back in the water.

Not sure about drilling the cutlass bearing and I would like to meet the marine engineer who drilled mine without telling me. Would have been nice if he took the shaft out before drilling and putting 3 little dents with burrs into the prop shaft. You can image what the shaft burns did to the rubber insert, not only from going round but in and out as the engine revs change the shaft moves in and out slightly. I did polish the shaft to a mirror finish but it wasn't enough, so in the Spring we will fit a new shaft.

Pete

 

[Poey50]

Not sure about drilling the cutlass bearing and I would like to meet the marine engineer who drilled mine without telling me. Would have been nice if he took the shaft out before drilling and putting 3 little dents with burrs into the prop shaft. You can image what the shaft burns did to the rubber insert, not only from going round but in and out as the engine revs change the shaft moves in and out slightly.

I drilled the P-bracket plus cutlass bearing with the shaft in place and expected it to be quite fraught because of the above dangers. In fact, it proved straightforward. As soon as the bearing case was hit the swarf changed from dull bronze to bright yellow. Going slowly and checking regularly a small black hole then appeared in the base of the drill hole - first sight of the cutlass bearing rubber. Further short drilling steps expanded this black hole and when it just became the same size of the rest of the hole I stopped. The shaft didn't get touched at any point. Tranona has already described the tapping - also straightforward.

 

[Neil_Y]

I

My Moody 35 will shortly come out of the water and have new 3 blade feathering prop fitted (featherstream). I also intend to fit a rope cutter and its a toss up between SPURS and Ambassador Stripper. SPURS slightly cheaper but I want to fit the best performing kit rather than the cheapest. Anyone with experience of either, your opinions of pros and cons would be welcome. Thanks in advance for your contributions!

know this is a bit old now....but why only consider these two? there is the cutter the RNLI use, the QuicKutter. I might be biased as we supply them, but may be worth doing a comparison