Steering Wire Pulley

Boathook

Boathook

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I need a replacement pulley like this one. The sheaves are about 2" diameter and suitable for up to 6mm diameter wire. I had this refurbished a fews years ago but one of the sheaves keeps jamming (the one with damaged edge) and the damage is caused by me trying to free it even after soaking. I've had a trawl of the web but can't find anything so any suggestions are welcome. To put bigger diameter pulley has been considered but it will mean altering the position of the others.

View attachment 48200View attachment 48199
 
Sheaves of various material and sizes are available.
Can you remove the axle? Maybe replace it with a bolt!
The casing would look better Hammerited!
AS you can see I'm a bodger!
 
cliff said:
Not quite the same but with a little fettling could be made to work by mounting on a decent backplate rather than using the long screw

http://www.ebay.co.uk/itm/CAST-IRON-SINGLE-DOUBLE-WHEEL-SCREW-PLATE-PULLEY-Clothes-airer-dryer-/190726522761

Or a cheaper one

[url]http://www.ebay.co.uk/itm/Extra-Double-Pulley-for-Kitchen-Maid-Pulley-Airer-/331281262002

[/URL]
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Thanks for the link cliff. They look a bit flimsy for turning my steering wires through 90 degrees. I've had a couple of pm's that I'm following up plus looking at refurbishing again, but this time with new sheaves.
 
From an engineering standards point of view, 2" is a terribly small pulley for 6mm wire! It will shorten the life of the wire.
About 6" would normally be recommended, and if it was a control cable on an aircraft, bigger than that. 2" OD would only be used for 3/32" wire.
The Jefa website says 100mm for 5mm wire and 140mm for 6mm wire. They say "It's not advisable to use 6 mm cable on the 100 sheaves as the cable will fatigue quickly due to the too small bending radius."
 
Plevier said:
From an engineering standards point of view, 2" is a terribly small pulley for 6mm wire! It will shorten the life of the wire.
About 6" would normally be recommended, and if it was a control cable on an aircraft, bigger than that. 2" OD would only be used for 3/32" wire.
The Jefa website says 100mm for 5mm wire and 140mm for 6mm wire. They say "It's not advisable to use 6 mm cable on the 100 sheaves as the cable will fatigue quickly due to the too small bending radius."
Click to expand...

6mm seems very big wire?
Bigger sheaves are always better, but using bigger wire than necessary can be counterproductive.
What load should we design to?
Fat helmsman putting all his weight on the wheel?
That's a lot on a yacht with a 5ft wheel and a small sprocket in the pedestal....
 
Plevier said:
From an engineering standards point of view, 2" is a terribly small pulley for 6mm wire! It will shorten the life of the wire.
About 6" would normally be recommended, and if it was a control cable on an aircraft, bigger than that. 2" OD would only be used for 3/32" wire.
The Jefa website says 100mm for 5mm wire and 140mm for 6mm wire. They say "It's not advisable to use 6 mm cable on the 100 sheaves as the cable will fatigue quickly due to the too small bending radius."
Click to expand...

The wire is actually 4mm and the set up is some of the orginal from the 70's and 300 boats were produced like this. Bigger pulleys, etc would ideal but I would be tempted to scrap wires and go hydraulic to be able to use a different route. Then there is the cost .............
 
You could also bin the wire and go for (say) Dynex Dux or Dyneema or Vectran and replace your sheaves with some hi- load blocks, but getting plain disk sheaves machined should be cheap enough...
 
Boathook said:
I need a replacement pulley like this one. The sheaves are about 2" diameter and suitable for up to 6mm diameter wire. I had this refurbished a fews years ago but one of the sheaves keeps jamming (the one with damaged edge) and the damage is caused by me trying to free it even after soaking. I've had a trawl of the web but can't find anything so any suggestions are welcome. To put bigger diameter pulley has been considered but it will mean altering the position of the others.

View attachment 48200View attachment 48199
Click to expand...

I Have serviced. My 8 M Catalac pulleys. The same ones by the look of the pictures several times.I knocked the axel out withe a punch a knocked the siezed sheaves out cleaned and sanded the sheave faces and replaced the axles proper old fashioned part threaded bolts (Both double pulleys) and the pain in the r's single pulley over the tank) greasing with waterproof grease. This year though I had to replace 1 sheave and a. Business in Padstow, Smiths turned me a new stainless sheave for a. Very reasonable cost at very short notice completing the delivery in an afternoon
 
As an after though,I araldite ed. The 4 bulkhead bolts into the sheave casing to put the single pulley back the original fitting must have been by a contortionist dwarf even if the tank hadn't been fitted! the new wires I fitted are galvanised(more flexible and less subject to fatigue than stainless) 5 mm which were the same as when we bought the boat, I carry sparewire. The original wire were on at least 6 years but I have grease ed them and the pulley s every year
The wires Take only 10 mins to change if the pulley s are in good fettle but don't cross them as I Did last year. Navigating though dozens of boats with crossed steering wires undersail is a shocking experience!!
 
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