Do I need to buy an anchor before fitting a hinged bow roller?

[altruistica]

I'm completing a 40ft cat after the original builder died five years ago. He had already bought a 24V Lofrans Kobra windless, a hinged bow roller, this one (https://www.force4.co.uk/item/Force-...Bow-Roller/TDP


He also has what I think is an anchor stop, in order to take the strain off the windlass once the anchor has set? I've reasoned that the 'flap' must be opened before operating the windlass (otherwise the anchor wouldn't drop), and then placed back down to lock the anchor and relieve the strain of the chain and anchor off the windlass. Is that right? See the video here:

https://www.youtube.com/watch?v=aUkMVMJObpU

Should I fit this lock once everything else is in place? ie. the last thing to fit.



Looking at the bow roller (mine is the one for anchors up to 20kg), there are six holes. If the roller is positioned so the roller doesn't hit the front of the boat, the four rear holes are positioned where the deck I think is 60mm thick (two 18mm plywood sheets, either side of 20mm Airex foam board and all epoxied together). Should I bolt all the way through this with nuts underneath? The front two holes are at the front of the boat above the cross beam, which is about 150mm thick. Should I bolt all the way through, or just use some 80mm M8 bolt screws? I've made a terrible film here:

https://www.youtube.com/watch?v=gL5G1gIy888

I really don't want to get this wrong, so maybe I need to get an anchor first to check how it is all going to sit. I think he was thinking of a 16kg Delta anchor.



Any help, much appreciated.

[MicHughV]

Considering that the anchor stop will take all the anchor strain, it needs to be fitted with a backing plate underneath the deck, a nice big thick plate, and each thru' bolt paired with a nice big washer.

[Kettlewell]

Yes! I would say to choose your anchor first prior to bolting everything down. Anchors vary widely in dimensions, including shaft length, curves, etc. I would highly recommend viewing Panope's videos to form your own opinion on what anchor to get. Skip the Delta--it is OK, but not the best. https://www.youtube.com/@flygoodwin

Typically a 40-foot cat would require at least a 20kg or larger anchor.

[MicHughV]

A 16 kg anchor seems to be a bit on the light side for a 40' cat, and I would consider upgrading the size and also adding a secondary anchor.

Forgot to add, that an anchor stop is designed to hold chain, if your rode is all chain is one thing, but if you use a chain/nylon combo, it will not hold nylon.

[altruistica]

Originally Posted by MicHughV

Considering that the anchor stop will take all the anchor strain, it needs to be fitted with a backing plate underneath the deck, a nice big thick plate, and each thru' bolt paired with a nice big washer.

Thanks for the reply. The anchor stop base, seems to be between three and five millimetres in thickness. Should I be looking for something the same dimension as the base, in five millimetres thick stainless then?

[MicHughV]

Yes, 5mm would be a good size thickness....make the plate a good 250mmx 250mm square and find the biggest washers you can for the hold down bolts.
Don't forget to slather everything in 3M 5200 caulk.
Stainless steel would be the preferred material, but if not, regular steel will do, if properly cleaned and painted.

[Tupaia]

An anchor stop is somewhat redundant on a cat since you nearly always use a bridle. If you have an all chain rode then it is useful when setting the anchor. If you have a combination chain/rope rode then a substantial cleat for the rope and a strop with a chain hook is much more practical.

[altruistica]

Originally Posted by Tupaia

An anchor stop is somewhat redundant on a cat since you nearly always use a bridle. If you have an all chain rode then it is useful when setting the anchor. If you have a combination chain/rope rode then a substantial cleat for the rope and a strop with a chain hook is much more practical.

I'm a newbie. Why do some rodes consist of just chain and others a combination of chain and rope. I understand the idea of a bridle (connecting the two hulls to the one rode). Could I mount two cleats to the cross member at the front (they could be bolted through the 150mm cross member) and attach the bridle to them? What is a strop with a chain hook?
Thanks.

[Tupaia]

Originally Posted by altruistica

I'm a newbie. Why do some rodes consist of just chain and others a combination of chain and rope. I understand the idea of a bridle (connecting the two hulls to the one rode). Could I mount two cleats to the cross member at the front (they could be bolted through the 150mm cross member) and attach the bridle to them? What is a strop with a chain hook?
Thanks.

Weight is a big issue on a multihull and the anchor rode is a heavy item. A combination rode 30-50m of chain spliced to 100-200m of rope gives flexibility to anchor in deep water when necessary but with a considerable weight saving, especially as the shallow draft usually means that 30-50m of chain is more than adequate.


Setting the anchor is done prior to deploying the bridle so you need some way to snub the rode without putting undue strain on the windlass. The chain stopper you have is not able to work on the rope part of a combination rode. A better solution is a strong cleat along side the normal route of the rode on deck. If you are in deep water the rope part of the rode is cleated off to set the anchor. When on the chain part of the rode, shallower anchorages, a short piece of rope spliced on to a chain hook can be hooked into the chain and the free end cleated off on the cleat allowing you to snub the anchor to set it.

[MicHughV]

All chain versus a chain/nylon anchor rode has been well discussed on this forum.

There is no simple answer to your question and there are proponents on both sides of the fence on this matter.

But as pointed out above, weight is a big issue on a multihull, and on this basis alone, I would recommend a chain/nylon combination. On my boat, my preferred set up is 75' chain, followed by nylon rode. This has worked well for me over 35 years afloat, but other people will have other preferred setups.

However, your snubber will not work on nylon rode, and as pointed out above, cats generally employ a bridal arrangement for their anchor systems.

My best advice is to walks the docks at area marina's and see how other cats manage this to give you some ideas how to set up your own arrangement.

Without being there on your boat, it's not practical for me and others on this forum to decide the matter for you. Besides walking the docks, it would be useful to find a multihull skipper who can come out to your boat and see in person some setups you could consider using.

For many, it's a trial and error procedure until you find something that will work for you. Experience goes a long way in this regard, and until you've anchored a few dozen times, you won't really know what works and what doesn't work.