Pulleys

salinia

salinia

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Does this look right? or do you consider it could be rigged to pull up from the bottom centre pulley?
Lifting Keel tackle on a Parker 235
6931836837_fb4c64d60a_z.jpg
 
Hard to be sure what's what since we can't see the whole of the tackle but the lead from the LH sheave looks poor and also looks as if it chafes on the plate it's passing through - assuming it does pass through of course!
 
Difficult one!
Hard to see, but...
Yours looks as if no rope is rubbing on any other when its block to block, which is as good as it gets.
Sometimes you can lose a great deal of friction by downsizing the rope.
 
salinia said:
Does this look right? or do you consider it could be rigged to pull up from the bottom centre pulley?
Lifting Keel tackle on a Parker 235
6931836837_fb4c64d60a_z.jpg
Click to expand...

Sounds Crazy? but if I remeber rightly in terms of pure rigging if there is space the blocks should at 90 degs to each other (my thinking keel block fore and aft).

I believe this is the set up you are looking for...

http://www.harken.com/rigtips/Reeving_Diagrams_6-1-Cam.php

Personally I would reave backwards IE 6 5 4 3 2 1.

It always takes a few trys :o
 
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I'd say not as one run will cross from one side of the bottom block to the other on the top block. Not a problem until at full lift the blocks are tight up to each other.

I think. ?
 
knuterikt said:
Where is the standing part attached?
Click to expand...

Standing part is attached to the bracket.
6788912472_4ec3d1e11e_z.jpg


The Harken diagrams are good and show one set up similar to mine in that it has 3 pulleys and two pulleys, my thinking is that the way it is set up in the photo it is pulling out of balance and would be better pulling from the middle. However my concern is that if I rig so that it pulls from the centre bottom pulley the crossing of the rope may cause chafe. I managed with it last season ok albeit a bit of a grunt but looking at the pic, I think centre pull would make it easier. I will have to experiment and check for chafe. Two Parker 235 owners have been in touch on the association forum and say their set up is the same as mine so perhaps I am fussing.
 
Just had another think about this and my picture shows the block and tackle with the weight taken off because the keel is resting on the trailer.
So when the weight is on my guess is that the pulley would come over from the vertical slightly and the alinement wouldn't be so poor perhaps.
 
salinia said:
Standing part is attached to the bracket.
6788912472_4ec3d1e11e_z.jpg


The Harken diagrams are good and show one set up similar to mine in that it has 3 pulleys and two pulleys, my thinking is that the way it is set up in the photo it is pulling out of balance and would be better pulling from the middle. However my concern is that if I rig so that it pulls from the centre bottom pulley the crossing of the rope may cause chafe. I managed with it last season ok albeit a bit of a grunt but looking at the pic, I think centre pull would make it easier. I will have to experiment and check for chafe. Two Parker 235 owners have been in touch on the association forum and say their set up is the same as mine so perhaps I am fussing.
Click to expand...

You must test this in place, but here is an idea..

Assuming the picture is taken looking aft
6931836837_fb4c64d60a_z.jpg

Starting from the standing part (I can see it now in your picture :)
Into port sheave of the lower block aft going forward
Turn the upper block 90° (sheaves athwartships)
Go through upper block forward sheave port to starboard
Go through lower block starboard sheave forward to aft
Go through upper block aft sheave starboard to port
Go through lower block middle sheave aft to forward
Go up to the cleat
 
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