Rope Clutch Install

[FraidNot]

Never installed one of these - but need to put in a double next to the ones that are aready there. On the deck - companionway roof at front of cockpit.
Is this a DIY job or worth getting a specialist for?
Haven't researched this task yet...

[Sailmonkey]

drill holes, seal core, re-drill holes, backing plates, bolt......
nope, you should be able to do this yourself.

[nigel1]

Originally Posted by Sailmonkey

drill holes, seal core, re-drill holes, backing plates, bolt......
nope, you should be able to do this yourself.

Thinking of adding a couple of clutches, when you say seal core, will any good quality marine sealant be OK

Thanks

[delmarrey]

What is meant by sealing the core is drilling a hole thru the to layer the same size as the thru bolt and then using a cut off allen wrench the clean out some of the core then fill it with epoxy. Let it cure then re-drill all the way thru.

Here is another thread discussing the procedure.

http://www.cruisersforum.com/forums/...tml#post149860

[nigel1]

Many thanks Delmarrey,

See straight away what you mean by sealing the core, picture is worth a thousánd words

[barnakiel]

Done same myself. Remember about installing some backing plates. And filling around the holes if cored deck.

b.

[Strygaldwir]

One of the easier things to do, just make sure of your backing plates and sealant.

[delmarrey]

I put mine up on a 1/2" riser to keep the lines off the deck, which keeps them fairly clean.

[thinwater]

Originally Posted by delmarrey

I put mine up on a 1/2" riser to keep the lines off the deck, which keeps them fairly clean.

It keeps us from doing half-way work. Nice work!

[unbusted67]

The allen wrench is to clear out the core to make a void for epoxy?

[clearsea]

Still have to seal to keep the water out. I like butyl tape. Several good sites describe the procedure. Not hard to do, but worth researching the task properly.

[s/v Jedi]

Originally Posted by unbusted67

The allen wrench is to clear out the core to make a void for epoxy?

For a cored deck and high load fasteners like clutches, winches etc. there a much better way:

Put the item to be fastened where you want it and mark and tape the area. Mark where the holes go. Now, take a holesaw as big as 1" unless the're not enough room for that size under the item (it would show with the item fastened). Go down in size but keep it as close to 1" as possible. Now, drill pilot holes through the top layer of fiberglass and the core but NOT through the lower layer of glass. Do the same with the hole saw. Now you can use a screwdriver to break the piece out (core will break). Use the dremel with drum-sander to remove more core from in between the two layers of glass. That biggest of the two sizes of drum sander bits is perfect. Make sure you get all the core of the underside of the top layer of glass. Sand it out with course paper and use the vacuum to clean (no cloths, chemicals). Now you can cast an epoxy plug in there using high-density filler. Use a match stick or tooth pick to work it under the upper layer, removing any air bubbles. After gelling you probably need to fair it a bit, use only high density filler for that too, make it thick if it isn't perfectly horizontal. After 24 hours holes can be drilled.

Click on the photo below for the complete album; I filled up the anti-slip under the bases of this cleat so that the compression force doesn't crush the anti-slip:

cheers,
Nick.

[FraidNot]

thanks all - very helpful.

Delmarrey - I'm not sure how you suggest using the allen key. Here is an example of what I think you mean - please tell me if wrong.

Drill hole of same size as bolt - lets say 10mm. Drill this through upper, core and lower layers.

Use allen key - lets say it splays out a diameter of 20mm, to enlarge the hole in the core layer (only).

So now there is a hole in the upper of 10mm, a 20mm hole in the core, and a 10mm hole in the lower.

Then tape over the bottom hole so the epoxy doesn't leak - fill the new bigger hole with epoxy - let dry and re-drill the 10mm all the way through.

Have it got this right ?

[s/v Jedi]

Originally Posted by FraidNot

Have it got this right ?

Yes. But you will find that this sounds much better in theory than in reality. If you have balsa core and the lay-up is done right, you will probably meet some polyester in there (encapsulating the end-grain balsa pieces) and the allen key can't grind that away. Also, When there's bits of core left on the bottom or under the top-layer, you still run the risk of crushing it when tightening the bolts. Last, the hole you work through is much smaller (fastener diameter) making it impossible to get all the air out while injecting the resin (it gets trapped under the top layer, creating voids). When you re-drill the hole for the fastener, you remove 60-90% of the plug that reaches all the way up to under the top layer of glass. There's very little support left to deal with the compression force.

cheers,
Nick.

[delmarrey]

Myself, I only drill thru the top layer of glass. Then use the allen to strip out the core and use a vacuum and a pick & hymostats to clear out the core material.

I'm not too worried about the crush. I use thick SS backing plates. My main obvective is to seal the core from water intrusion.

I've bent and broken my fair share of allen wrenches but I keep a good supply of harden ones around. The cheep ones just twist off fairly quick.

I use a syrunge to fill the holes from the bottom, up drawing out the syrunge as I go. This helps to eliminate air bubbles but sometimes I have to go back and dig out an area and add some more after a cure. If you wait around and leave a bulge above the hole one can force the semi-cured epoxy down into the hole some more. Epoxy will actually shrink after it cures so add a little extra on the surface and monitor it as it's curing to keep the hole full. Sometimes I'll actually add a bit more later to fill a crater that has started.

I'm not sure I like the holesaw idea with the flexing of the hull, especially under clutches, organizers and winches, I feel it may crack around the edges unless one were to put some layers of glass over it.