Proper Rope Clutch Size

[Tigi Too]

Hello!
I am new to the forum so if I am making any forum faux pauxs please be patient!

OK we have a Newport 41 mk II and we have been using Spinloc XTS triple rope clutches. The halyard (10mm) has always slipped and now our Asym Kite halyard (10mm) is slipping. I suspect the jib halyard is slipping but it is not as noticeable. After numerous emails with Spinloc (they have been as helpful as they can be) I am trying to ascertain if I need to go the next level rope clutch?
It appears one big question is what is the load at the clutch - if I can figure that out I can then spec out the clutch - perhaps going to a Lewmar D2.
So any thoughts-suggestions-help would be greatly appreciated! Thanks.
This has come on the heels on seeing a friend's recently purchased J122 and he seems to have bigger clutches than mine.
Dieter Hugel

[Stumble]

Hey Dieter,

Generally the recommendation is to use a clutch where the line is in the upper range of the size... So a 6-10mm clutch works best with 10mm line. With really highly loaded lines like racing halyards the only thing I have seen that really works is a double clutch. Where the line runs through both of them. If you go look at Lesson #1 they use this on the main halyard.

Downside is you have two clutches. Upside is you can ease the line simply by working the clutches.

[Tigi Too]

Stumble:

Do I know you? Not sure who this is? Thanks.

Dieter

[Stumble]

Dieter,

Sorry, I thought my name was in the signature.

Its Greg Rubin, We own 'So Far' in New Orleans.

[Tigi Too]

Greg:
Many thanks for sharing. OK so my 10mm is in the middle of the range - 12mm still seems to slip - slightly. I have changed the cams but not the base plates - do you think a base plate change would help or just wishful thinking?
I put a tension gauge on the halyard and it was about 930lbs of pressure.
I will go look at Lesson#1 but am trying to keep cabin top as clean as possible. Any other thoughts?

BTW my direct email is dmichaelhugel@g-c-m.com.

Hope to see you around the pier sometime!
Best!

Dieter

[Stumble]

There are a couple of ways to minimize slippage, i just depends on how exotic you want to get.

-Replacing the base can help if it is just worn jaws.
-Adding a second clutch is probably the easiest solution.
-Switching to a 2:1 halyard would reduce the load on the line by half which will help a lot. It also reduced mast compression which is a nice benefit.
-Adding a halyard lock will eliminate the problem entirely. But is a bit overkill for what you are doing.

There are also some procedural steps you can take.
- Tighten the halyard with the clutch open, then close it once the sail is up will help.
- Slowly easing tension off the winch will help
- Using the cunningham to make up the slack