55 or 65lb Mantus Anchor for my 2015 Jeanneau 409?

[DDabs]

So it seems that the S120, 55 lbs., would be comparable with either the A100, which is 20 lbs. or the A140 which is 44 lbs. So either way you're saving a little weight off the bow with the same holding properties. Correct?

[noelex 77]

Originally Posted by Mike OReilly

Good question ... according to Spade website: "All SPADE anchors of the same size, regardless of the material they are made of, will work with the same efficiency."

The steel spade is an excellent anchor, but in my opinion the aluminium version is not as good. The difference is especially apparent in hard substrates.

BTW Spade do, sort off concede this, although the official view is the holding power of the steel and aluminium versions is the same.

FAQs

"This is true; the model in steel will dig in slightly more readily than the equivalent aluminium version."

[Gerrycooper56]

Do you have all chain?


Sent from my iPhone using Cruisers Sailing Forum

[Mike OReilly]

Originally Posted by DDabs

So it seems that the S120, 55 lbs., would be comparable with either the A100, which is 20 lbs. or the A140 which is 44 lbs. So either way you're saving a little weight off the bow with the same holding properties. Correct?

Can't say. I really haven't studied their anchors that closely. But this sounds right.

Originally Posted by noelex 77

The steel spade is an excellent anchor, but in my opinion the aluminium version is not as good. The difference is especially apparent in hard substrates.

BTW Spade do, sort off concede this, although the official view is the holding power of the steel and aluminium versions is the same.

FAQs

"This is true; the model in steel will dig in slightly more readily than the equivalent aluminium version."

Thanks very interesting noelex. This makes sense to me in that, in my expereince, weight definitely helps with anchor set. The harder, or the weedier, the bottom is, the more initial weight matters.

[noelex 77]

Originally Posted by Mike OReilly

If a 55# Spade truly is a storm anchor for my boat, and by storm it means holding in over 100 knots, or even over 80 knots, then I definitely want one.

The force on an anchor in 100 knots will be nearly three times the force experienced at say 60 knots, so you would think it would be an easy question to answer, but the ultimate holding power of an anchor varies enormously with different substrates. Even if we confine the discussion to "good" substrates the answer will still have a lot of variation.

Then we need to factor in how much dynamic force will be present from wave action.

You only have to look at the fluctuation in results between individual pulls in anchor tests despite selecting areas with supposedly "consistent" substrate. Some anchor tests have such wild variations from one trial to the next, that few conclusions can be drawn with any statistically certainty.

I think the anchor size tables are at best gross approximations and in storm force winds all bets are off.

[Panope]

Originally Posted by Mike OReilly

Good question ... according to Spade website: "All SPADE anchors of the same size, regardless of the material they are made of, will work with the same efficiency."

This makes sense to me since weight is not what you are ultimately holding on, it is surface area and the ability to dig into the substrate. Weight does help with setting though, as does weight distribution and shape.

I agree, Mike.

For what it is worth, I had the opportunity to test identically sized Excel anchors (one steel 50 lbs, one aluminum 27 lbs). Initial setting was very similar. Ability to dive into the seabed after setting was similar. Holding power is likely very similar (boat not powerful enough to fully test this).

The difference between the two was revealed only during my 180 degree reset test with the lighter aluminum anchor being not as reliable.

Steve

[Kenomac]

Mike,

Buy an Ultra Anchor along with an Ultra swivel.

[Mike OReilly]

Originally Posted by noelex 77

The force on an anchor in 100 knots will be nearly three times the force experienced at say 60 knots, so you would think it would be an easy question to answer, but the ultimate holding power of an anchor varies enormously with different substrates. Even if we confine the discussion to "good" substrates the answer will still have a lot of variation.



Then we need to factor in how much dynamic force will be present from wave action.



You only have to look at the fluctuation in results between individual pulls in anchor tests despite selecting areas with supposedly "consistent" substrate. Some anchor tests have such wild variations from one trial to the next, that few conclusions can be drawn with any statistically certainty.



I think the anchor size tables are at best gross approximations and in storm force winds all bets are off.

Agree entirely, which again is/was why I was so surprised at the claim made by Spade. And which is why I sought clarification.

It's also what makes anchor threads such fun.


Why go fast, when you can go slow

[Mike OReilly]

Originally Posted by Kenomac

Mike,



Buy an Ultra Anchor along with an Ultra swivel.

They look good, and pretty ... and damn expensive. Wanna buy me one for my birthday [emoji1]


Why go fast, when you can go slow

[Jim Cate]

FWIW, I have seen one aluminium Spade with a badly bent shank. 'Twas on a ~55 foot catamaran named "Cable's Length", and the owner was pretty unhappy with that anchor. From memory, it was replaced with a steel Spade, but I'm hazy on that. And I dunno if Spade replaced the anchor under their warranty... this was some years ago.

Jim

[Spade Anchor]

Wow, Its hard to take a weekend off! HaHa.

To clarify, when we recommend a storm anchor, we are referring to hurricanes as the storm. At least a class 1 with 60+ knot winds , up to 80 knots. Currently there is not a variable testing option to test beyond that.

We have testimonies of Spade users going though cat4 hurricanes, every testimonial states they were the only boat left in the harbor. With multiple testimonials of going though cat 3 hurricanes on the Aluminum Spade anchor. We do not have a documented cat5 on record.

Sorry for the delayed response but it was the weekend.

[Mike OReilly]

Originally Posted by Spade Anchor

Wow, Its hard to take a weekend off! HaHa.

To clarify, when we recommend a storm anchor, we are referring to hurricanes as the storm. At least a class 1 with 60+ knot winds , up to 80 knots. Currently there is not a variable testing option to test beyond that.

We have testimonies of Spade users going though cat4 hurricanes, every testimonial states they were the only boat left in the harbor. With multiple testimonials of going though cat 3 hurricanes on the Aluminum Spade anchor. We do not have a documented cat5 on record.

Sorry for the delayed response but it was the weekend.

Thanks Spade. I really appreciate the clear answer. That's all I was asking. This makes Spade stand out above the rest. Thanks

(But to be clear, I asked the question on Thursday at 13:24. You responded to other queries from other people in this thread after that time, so I guess you just missed my follow up question.)

[sailorboy1]

I don't really understand these threads anymore. Other than saving a few dollars why wouldn't the answer always be to install the biggest anchor that fits on a cruising boat? Seems to me that all the "if this" "if that" are crazy worries that distract you from your goal of increasing the holding and your peace of mind about your anchor.

I have a 60# anchor on my boat because that shank on that already bounces off the bottom of the furler and I couldn't fit an 80# ( I still seriously considered the 80#). And yes I've have to pull it up by hand solo with 30' chain when the windlass broke.

[ErikFinn]

Originally Posted by sailorboy1

I don't really understand these threads anymore. Other than saving a few dollars why wouldn't the answer always be to install the biggest anchor that fits on a cruising boat? Seems to me that all the "if this" "if that" are crazy worries that distract you from your goal of increasing the holding and your peace of mind about your anchor.

I have a 60# anchor on my boat because that shank on that already bounces off the bottom of the furler and I couldn't fit an 80# ( I still seriously considered the 80#). And yes I've have to pull it up by hand solo with 30' chain when the windlass broke.

I think you are absolutely correct.
Must be that some folks have not read the anchor threads and have thus missed the priceless education.

[Mike OReilly]

Originally Posted by sailorboy1

I don't really understand these threads anymore. Other than saving a few dollars why wouldn't the answer always be to install the biggest anchor that fits on a cruising boat? Seems to me that all the "if this" "if that" are crazy worries that distract you from your goal of increasing the holding and your peace of mind about your anchor.

I have a 60# anchor on my boat because that shank on that already bounces off the bottom of the furler and I couldn't fit an 80# ( I still seriously considered the 80#). And yes I've have to pull it up by hand solo with 30' chain when the windlass broke.

We may be saying the same thing, but I think you should have the largest new-gen anchor your boat's anchoring system can reasonably manage. By system I mean roller, windlass, rode, engine and you.

I think it is possible (although unlikely) that you can go too big for your bower. Too big could lead to poorer outcomes due to inadequate set or poor choices with regards to multiple attempts when the first set fails. An anchor doesn't ultimately hold on weight, it holds by surface area in contact with substrate. A poorly set monster anchor will drag just as a severely undersized one will.

Proper anchoring is as much (or more) about good technique as it is about how big your pointy metal thing is. Too big can interfere with good technique.