Trying to find what I think is a cheek block

ProDave

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Like this one.

cheekblock.jpg

Crucially it has a plastic backing plate shaped to match the curve of the boom.

The new one we want is for use with 10mm diameter line.

I have found lots of blocks, very few are 4 hole mounting like this, and none yet with a matching backing plate. Any ideas please?
 

B27

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You can shape the block by taping some sandpaper to the boom and rubbing the block on it.

But really it's much better to get a 4 sheave end fitting for the boom and run the lines internally.

That avoid the nonsense of the blocks always being in the wrong place as shown in the photo, where someone has fudged the issue by turning the block the wrong way around running the line outside the block. An arse-about-face cheek block or arsecheek block for short?
 

Aja

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You can shape the block by taping some sandpaper to the boom and rubbing the block on it.

But really it's much better to get a 4 sheave end fitting for the boom and run the lines internally.

That avoid the nonsense of the blocks always being in the wrong place as shown in the photo, where someone has fudged the issue by turning the block the wrong way around running the line outside the block. An arse-about-face cheek block or arsecheek block for short?
I don't see why the block can't just be reversed 😊
 

ProDave

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I'm about to remove something like that from my boom. Let me know if you want it, otherwise it is going in the skip.
Yes please, I will pay postage. PM me.

Yes the existing block is indeed the wrong way round. That is how it was when we got the boat, and it was not in use. We have been experimenting with alternative reefing ideas this morning as the existing arrangement with the lines running inside the boom is unworkable, way too much friction. We have tried all sorts, different lines and just can't get it to work. The basic problem is lines inside the boom do not exit via blocks but plain sheaves = more friction. Line exiting at front of boom exists downwards so has to go over another block on the deck and back up = yet more friction. We are trialling ideas with the reefing on the outside of the boom = 2 simple blocks low friction no unecessary blocks.
 

William_H

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Yes, ProDave that block looks to be the wrong way round for the rope direction
Note the load on the outer end of the axle of the sheave is supported by the mount and flat plate to the right in the picture. It is mounted back wards in the picture such that the support to the outer end of the axle is in compression. Much better around the other way in tension. (pull support) However probably still ok in service depending on loads on reefing line. Just not as intended. ol'will
 

ProDave

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My new cheek block arrived today.

Slight issue. Yes it does have a plastic backing plate that I could sand to match the curve of the boom, BUT un the centre of the SS back plate is a protruding boss on the back. The plastic back plate appears to exist just to level that up, with the plastic plate having a hole in it to clear that. So no chance of sanding that plastic plate or else the boss will protrude in the middle.

So separate back plate?
Or just a couple of washers under each fixing screw? (yes that sounds like a bodge I know)
 

Daydream believer

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2 narrow strips of plastic each side, so a channel is formed in the centre.
Plastic could be from an old 5 gallon plastic container as the material would likely have a less harsh surface to surface contact with the boom.
 
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