OK to drill a hole through anchor?

[Travelling Westerly]

Ive got a new Knox anchor that just fits on the stemhead/bow roller OK. The only problem is there is no hole in the shank to fit a pin through to secure it in place. Is it OK to go ahead and drill a hole through it so I can pin it in place? I dont want to ruin it but really need to ensure its secure when underway.

Thanks

 

[Adios]

It will rust where you drill it. Drop of paint once a season will help but not be as good as galvanised. Still much better than it getting loose at the wrong moment! It won't suddenly rust away so it won't be ruined.

 

[Bouba]

It’s practically encouraged

 

[Robih]

Drilling will probably invalidate any warranty. Could you lash it securely? That’s what I’ve always done. I’ve heard of large fluke anchors having sufficient force to bend a retaining pin after head butting large seas. That’s a worry as a bent pin may prevent its removal - so it becomes a safety issue.

 

[salar]

I would never deliberately damage the galvanising coating, it will open it up for rust and that's not what you want dripping onto a deck or down the bows. I have a stainless snap shackle rigged to clip to the anchor to retain it. Never had a problem with that method.

 

[noelex]

The Knox is a strong anchor, but it is still not a great idea to drill extra holes in the shaft.

Can you lash the anchor down instead? This also removes the (admittedly rare) problem of bending the retaining pin. A bent pin can make it very hard to free the anchor in a hurry. Lashing can always be cut if it jams.

 

[lustyd]

Drilling will probably invalidate any warranty. Could you lash it securely? That’s what I’ve always done. I’ve heard of large fluke anchors having sufficient force to bend a retaining pin after head butting large seas. That’s a worry as a bent pin may prevent its removal - so it becomes a safety issue.

More importantly, wouldn't it then invalidate the type approval for insurance? Surely a piece of cord to tie it on would be sufficient?

 

[Neeves]

The anchor has a roll bar - perfectly located to allow you to lash it on.

Jonathan

 

[SimonKNZ]

I've recently added a short length of rope to the bitter end eye bolt near the windlass, with a stainless snap hook on the free end. This clips onto the anchor shackle. I figured it's only there to hold the anchor if the windlass accidentally veers, so keep it simple

 

[roaringgirl]

The Knox is a strong anchor, but it is still not a great idea to drill extra holes in the shaft.

Can you lash the anchor down instead? This also removes the (admittedly rare) problem of bending the retaining pin. A bent pin can make it very hard to free the anchor in a hurry. Lashing can always be cut if it jams.

I don't think it's rare, I've bent 3 pins in 7 years of ownership so far. If I'm just doing a short sail in light seas or downwind, I might use a pin as it's quicker and easier, but anything into a sea, or for more than a couple of hours and I'll lash it.

 

[Neeves]

I've recently added a short length of rope to the bitter end eye bolt near the windlass, with a stainless snap hook on the free end. This clips onto the anchor shackle. I figured it's only there to hold the anchor if the windlass accidentally veers, so keep it simple

There is a chance that in big seas the anchor can lift off and away from the bow roller, depends on design and if there is anything else to restrain the anchor (our bow roller is designed to constrain the anchor). On passage we would follow roaringgirl's practice - lash it down.

We also do what SimonKNZ suggests and have a short strop from a strong point, in our case to the chain just aft of the shackle, we use the same strop (and chain hook) as back up to our bridle.snubbers at anchor - as Simon says - keep it simple.

Jonathan

 

[Bouba]

I made a stainless steel guard that bolts onto the bow roller to catch the anchor if it bounced.

 

[Travelling Westerly]

The anchor has a roll bar - perfectly located to allow you to lash it on.

Jonathan

That's what I currently do but it still allows a bit of movement which is my worry as the tip of the fluke just touches the stainless hull plate under the stem head. I wanted the anchor just positioned an inch out and away from the plate then pinned in place.
Maybe a bit of wood or something to stop it fretting on the tip and then continue to lash it down?

 

[Neeves]

That's what I currently do but it still allows a bit of movement which is my worry as the tip of the fluke just touches the stainless hull plate under the stem head. I wanted the anchor just positioned an inch out and away from the plate then pinned in place.
Maybe a bit of wood or something to stop it fretting on the tip and then continue to lash it down?

The normal solution is to lash it such that it does not move forward (and wobble) by lashing is back onto the roller itself. You could lash it by pulling it forward, slightly, and with the same piece of rope lash it back.

If an anchor is left to wobble - it can wear the roller. I have seen 'wobble plates' restrictions made from any polymer (chopping boards seem popular) simply bolted in side the sides of the roller so that they restrain the shank but don't restrict the shackle.

Jonathan

 

[rogerthebodger]

I have drilled 20 mm dia holes in both my anchors before I had then galvanized.

BTW I fabricated all my anchors but I very really anchor along our coast.

Note the 2 20mm dia drop nose pins attached with chains in case I drop the pin.

 

[ithet]

I drilled a hole for a pin in my Delta. Due to the hardened steel it was not easy and required a cobalt drill. I would expect similar for you Knox. My anchor was second hand so no warranty issues

Having said that, I would prefer a retaining hoop as the pin does bend.

 

[Neeves]

Roger,

I do respect your opinions in this forum, perhaps because I admire the work you have completed for a yacht I can admire

BUT, there is not always a but - except in this case.....

Can I suggest you separate your bent link, that self rights the anchor on retrieval, from the shank by adding at least one shackle and if you have room a couple of chain links. I may interpret incorrectly but your bent link (aka Boomerang in Neeves' speak) extends the shank, or the lever arm of your shank, by 30% -50% and were you to have your anchor well set, or irretrievable (except by diving) - you may bend something, possibly the bent link.

You also appear to have a 'conventional' galvanised swivel from the lifting industry, a stainless swivel from a local chandler AND the bent link. This looks like redundancy gone mad - you either need one swivel or a bent link and certainly not 2 swivels. The stainless swivel might be held together by a very questionable weld - and unless its top of the range (I'd dump it, now). I suspect the swivel that I identify as coming from the lifting industry is a G30 model, which should have been batch tested and you can see the quality of how it has been constructed. I have tested these swivels and they generally fail where the 'D' link is welded on - but the stainless marine swivel usually fails for some hidden defect 'inside' the barrel.

Finally swivels actually don't work, by them selves, they only work with manual intervention. I'd suggest allowing twists and hockles in the chain to fall out with torque and gravity and just use the bent link, separated by a couple of chain links.

Anchor Swivels: Caution Required - Practical Sailor

How Well Do Swivels Reduce Twist? - Practical Sailor

How to boomerang your anchor right back at you - MySailing.com.au

I only include this last link as it explains how we join our Boomerang to the anchor.

Stay safe and take care - especially where you are.

Jonathan

 

[noelex]

When looking to secure the anchor when underway, a “devils claw” can be a useful accessory. It allows high tension on the anchor chain, locking the anchor into the bow roller, and importantly does this without any load on the anchor windlass.

See photo below of our boat (during construction). The “devils claw” can be seen attached to chain stopper:

 

[rogerthebodger]

Yes you are correct the banana is in the wrong place and the 2 swivels are not required. I have in fact modified the banana as the anchor attachment some tines turned the anchor the wrong way so the anchor came on to the bow roller 180 degrees out.

I as I said I don't anchor much so low on my to do list.

 

[lustyd]

Yes you are correct the banana is in the wrong place and the 2 swivels are not required. I have in fact modified the banana as the anchor attachment some tines turned the anchor the wrong way so the anchor came on to the bow roller 180 degrees out.

I as I said I don't anchor much so low on my to do list.

Well now I've seen everything! A cordial exchange about anchors with complete agreement. Never thought I'd see the day