what is the smallest sheet clutch you can buy

[Whitelighter]

I have a project for my tender crane, but a clutch of some sort to stop a rope running free looks like it might be required.
We are using 6mm dynema, can I get a clutch that small? I know mostly they are used for sheets etc which are a greater diameter.

 

[Ingwe]

Yes spinlock (and I presume other manufacturers) do clutches that will take diameters down to 4mm. If you look on the spinlock website they have graphs showing the expected holding power with different diameters of line which is worth looking at before you buy as the holding power on the smaller lines is obviously significantly less.

 

[lw395]

Not exactly a clutch:
https://www.tcschandlery.co.uk/spin...MIteCP2eqh3AIVAhwbCh1fbw62EAQYASABEgJLIvD_BwE
Plenty of other cam cleats.
A clam cleat mght be appropriate if you don't want it easy to release with the load on.

 

[Whitelighter]

Useful thank you

 

[Amulet]

Not exactly a clutch:
https://www.tcschandlery.co.uk/spin...MIteCP2eqh3AIVAhwbCh1fbw62EAQYASABEgJLIvD_BwE
Plenty of other cam cleats.
A clam cleat mght be appropriate if you don't want it easy to release with the load on.

I bought these for my lazyjacks. For my purpose it was a mistake. They are very fancy expensive cleats. The key functionality they provide is to cleat and uncleat holding the rope a fair distance from the cleat - dinghy control lines. They were just annoying for my use because it was easy to knock them uncleated and not easy to see whether they were cleated. A pair of cheap cam cleats replaced them, and do the job very well.

This does not necessarily mean they are not fit for your purpose.

If you are anywhere near Oban I have a couple going cheap!

 

[lw395]

I bought these for my lazyjacks. For my purpose it was a mistake. They are very fancy expensive cleats. The key functionality they provide is to cleat and uncleat holding the rope a fair distance from the cleat - dinghy control lines. They were just annoying for my use because it was easy to knock them uncleated and not easy to see whether they were cleated. A pair of cheap cam cleats replaced them, and do the job very well.

This does not necessarily mean they are not fit for your purpose.

If you are anywhere near Oban I have a couple going cheap!

We have them for spinny halyard on a dinghy.
I think they have a few plus points.
1) they resist a high load on a thin rope.
2) they are 'straight through' zero friction when uncleated.
3) they are easy to release when highly loaded.
4) unlike a cam cleat, they don't 'cleat' until some load comes on the line. A slack line will run through with low friction and no wear.
You are not alone in finding them annoying when you can't see if they're cleated or not, and when they release when you don't want that.

On consideration, I don't think I'd use them in the OP's application, too easy to release.
I'd probably use a clamcleat, because it won't release easily with a big load on it. But I'd be suspicious of it becoming insecure with wear.
I use a clamcleat for a highly tensioned 4mm dyneema dinghy halyard, but if it slips, nobody gets hurt, I just lose a little speed and buy a new cleat or rope next day.