Any down sides to replacing cheek block with single?

[GHA]

Can't see any major issues but you never know.....

Bit of a refit going on, these are probably 35 years old and in the bin already...

So rather than faff about finding a suitable replacement then getting the angles all set up thinking is just weld on a bit of stainless & rig something along the lines of..

Upside - Less fabrication to do, easy to replace if it goes bang somewhere in the middle of nowhere, should self align perfectly under load.

Downside - Might flap about a bit but little bit of bungie should keep things quiet, .

and..........................

tia

 

[JohnDL]

Can't see any major issues but you never know.....

Bit of a refit going on, these are probably 35 years old and in the bin already...

So rather than faff about finding a suitable replacement then getting the angles all set up thinking is just weld on a bit of stainless & rig something along the lines of..

Upside - Less fabrication to do, easy to replace if it goes bang somewhere in the middle of nowhere, should self align perfectly under load.

Downside - Might flap about a bit but little bit of bungie should keep things quiet, .

and..........................

tia

That is what I did for my spinnaker sheets, even to the make of the replacement block and the use of shock cord. Try looking for an off the shelf bolt through pad eye which will save a lot of time and money - the block can go straight on to it. Check the angles and distance to the winch on both sides of the boat (remembering the rope goes on clockwise so the angles and distance can be very different), if too close you may end up with riding turns as I did on one side, fortunately fixed by using a slightly smaller block - although in my case it was a bit academic as I take the sheet to the cabin roof.

Edit: just caught on the edge of this pic (click on it for a larger view):

 

[GHA]

That is what I did for my spinnaker sheets, even to the make of the replacement block and the use of shock cord. Try looking for an off the shelf bolt through pad eye which will save a lot of time and money - the block can go straight on to it. Check the angles and distance to the winch on both sides of the boat (remembering the rope goes on clockwise so the angles and distance can be very different), if too close you may end up with riding turns as I did on one side, fortunately fixed by using a slightly smaller block - although in my case it was a bit academic as I take the sheet to the cabin roof.

Edit: just caught on the edge of this pic:

View attachment 68135

Cheers, couldn't see why it wouldn't work but you never know.......

Try looking for an off the shelf bolt through pad eye which will save a lot of time and money

Ha!!! Not a chance A lot of the reason for the refit is to get rid of all the holes in the steel deck and get everything welded on so the rust will stay away... There's another extended thread mentioning this sort of thing...
Half hour with a grinder & welder should do it, some stainless knocking about already. After staring at it for a few days to see how it can be combined with some other handy use

Thanks

 

[prv]

Try looking for an off the shelf bolt through pad eye

I believe the OP has a steel boat, one of the advantages of which is the absence of holes to become potential leaks. So I imagine he would prefer to weld on a fitting than to drill holes in his deck

Otherwise, all seems like a good plan. I have the same. One thing I have learned is that with a bungee running up to the guardrail to support the block when not in use, if there isn’t quite enough tension in the bungee then the block shackle can start tapping noisily against the fixed eye (perforated toe-rail in my case) as the guardrail bounces up and down slightly in the wind. There needs to be enough tension to prevent that, yet enough stretch for the block to move around freely in use, which might require a longer length of bungee than is at first apparent. I had to move its top end from the lower guardrail to the upper.

Pete

 

[JohnDL]

Otherwise, all seems like a good plan. I have the same. One thing I have learned is that with a bungee running up to the guardrail to support the block when not in use, if there isn’t quite enough tension in the bungee then the block shackle can start tapping noisily against the fixed eye (perforated toe-rail in my case) as the guardrail bounces up and down slightly in the wind. There needs to be enough tension to prevent that, yet enough stretch for the block to move around freely in use, which might require a longer length of bungee than is at first apparent. I had to move its top end from the lower guardrail to the upper.

Pete

Strong shock cord to the top guard rail and just in front of first available stanchion so it does not slip back works for me.

 

[PuffTheMagicDragon]

Rather than a fiddly bungee cord you might wish to consider a stand-up pulley block.

 

[rogerthebodger]

I have cheek blocks as you have feeding my jib sheets to the winches and yes it was a bit fiddly getting the angle correct.

When I set up my spinker sheet feed blocks I did exactly as you propose but I did has some U-bolts handy in the rear deck.

Do you have any spray in insulation if so be careful about welding near by. I had some set on fire during construction. Quit exciting !!

 

[GHA]

Do you have any spray in insulation if so be careful about welding near by. I had some set on fire during construction. Quit exciting !!

No insulation in the lazarette but I want to change some stuff on deck further forward, which will be a bit of a nightmare taking the headlining down & chipping away the insulation.

Oh well, such is the cruising life - time rich if not cash rich.

 

[Javelin]

As an aside, on the example photo of the block you propose to use.
Looks like a lewmar one to me or possibly a Selden.
Both suffer from pretty aggressive uv degradation to the plastic cheeks, although Selden say they have improved the protection recently.

I've seen a lot of these blocks fail in the last couple of years.

 

[GHA]

As an aside, on the example photo of the block you propose to use.
Looks like a lewmar one to me or possibly a Selden.
Both suffer from pretty aggressive uv degradation to the plastic cheeks, although Selden say they have improved the protection recently.

I've seen a lot of these blocks fail in the last couple of years.

Ta, any recommendations for a suitable block?

One downside of living aboard is not having an address can make life tricky for shopping.., so whatever it is will most likely come from a chandlers somewhere mid scotland way where I'm visiting for xmas. It was a lewmar randomly picked from here in the pic -
http://www.duncanyacht.co.uk/index.php?route=product/category&path=2_10_11

 

[Javelin]

Well you get what you pays for.
I would look at these, probably in this order IMHO, but there are others.
Karver,
Harken,
Ropeye,
Schaefer,
Ronstan,
Antal,
Allen,
New Selden,
Barton,
RWO,
Lewmar,

As a guide, on my boat it would be Harken but I could live with Ronstan.

 

[JohnDL]

As an aside, on the example photo of the block you propose to use.
Looks like a lewmar one to me or possibly a Selden.
Both suffer from pretty aggressive uv degradation to the plastic cheeks, although Selden say they have improved the protection recently.

I've seen a lot of these blocks fail in the last couple of years.

I used Seldon for the price / swl ratio but, when I remember, I take them off and store below when not on board in case some light fingered scrote comes along. The price of Harken being eye watering.

 

[JohnDL]

Rather than a fiddly bungee cord you might wish to consider a stand-up pulley block.

I looked at something similar but it did not have the articulation needed for spinnaker sheets. Also the op wants to weld them on.

 

[GrahamD]

Remember that, as this is a cheek block, the maximum working load of the block you fit, and how you attach it needs to be at least x2 the max load generated by the headsail, and then some. This is not something to skimp on.

 

[GHA]

Remember that, as this is a cheek block, the maximum working load of the block you fit, and how you attach it needs to be at least x2 the max load generated by the headsail, and then some. This is not something to skimp on.

Almost but not quite, the max shear load on the fastening point to the deck will be 2 x tension on the line, the MBS of the block will be given as the tension on the line. (Edit - not completely sure about that now , the data available is flimsy ) (Edit again, digging deeper, think you're right, MBS looks like it is pulley failure, good call :encouragement: )

Not really a problem on a steel deck, even a little tack weld each corner of whatever gets used would probably be enough so full weld all the way round will be massive.

Might well be combined to create a fixing point for a jordan series drogue each side as well, now they most definitely will need to be strong!

 

[PuffTheMagicDragon]

I looked at something similar but it did not have the articulation needed for spinnaker sheets. Also the op wants to weld them on.

I think that it would certainly have much more articulation than a cheek block!