Only One Anchor

[BigCat]

I'm not going into the anchor business, but I am going to have Bugel type anchors made of 5086 H116 aluminum for my own use. I am making them quite a bit wider than the original and adding a tapered reinforcement down the center line from the shank attachment to the tip of the fluke.

[Alondra]

From the med on, most people seem to use a bugel, ours is quite heavy for the boat but has a super holding! I trust it!

[BigCat]

Originally Posted by Alondra

From the med on, most people seem to use a bugel, ours is quite heavy for the boat but has a super holding! I trust it!

Maxing Out loves them, too-but he also has a huge one - 70 pounds or about 31 kilos for a Privilege 39 cruising cat. The standard Bugel fluke is about 81% of it's length. I am keeping the proportions and angles of my modified Bugels the same except for widening the fluke to about 103% of the length, making its fluke area about 21% larger, which is similar to the newer NZ anchors. I also plan to run a stiffener down the center of the fluke that tapers from a couple of inches high where it joins the stock to nothing at the tip, since I am increasing the area of the fluke and thus the stress on the fluke.

[Ancora Latina]

Originally Posted by BigCat

I also plan to run a stiffener down the center of the fluke...., since I am increasing the area of the fluke and thus the stress on the fluke .

Did you also think at the possibility to fold the tip into a « V » as it twill give more strength, without adding weight – and also it would improve the penetrating angle??

A.L.

[wolfenzee]

No anchor is superior for all types of bottoms, my main anchor is a 22lb Bruce on 300' of chain, with a 45lb Forfjord as a storm anchor, a 30lb Danforth type (made before the "Danforth" with a cast shank) and a lightweight NorthHill kedging anchor, none of those were on your list. I still plan to pick up a CQR to complement my Bruce (strong point of one is the weak point of the other and vs.vs.).

[BigCat]

Originally Posted by Ancora Latina

Did you also think at the possibility to fold the tip into a « V » as it twill give more strength, without adding weight – and also it would improve the penetrating angle??

A.L.

Yes, I designed a version where the fluke was cut into two parts and welded in the middle to give the whole fluke a 'v.'

[Ancora Latina]

Originally Posted by BigCat

Yes, I designed a version where the fluke was cut into two parts and welded in the middle to give the whole fluke a 'v.'

Hi Big Cat,

I don't know if your drawing is exact or not?? From what I can see of it, your BSH (*) has a much too small radius.

When our anchor will be assembled, check if it will turn itself in the initial penetration position. If not, you will have to change the BSH to one with a bigger radius..

Good luck for the construction

A.L.
(*) BSH = Big Stupid Hook

[BigCat]

Originally Posted by Ancora Latina

Hi Big Cat,

I don't know if your drawing is exact or not?? From what I can see of it, your BSH (*) has a much too small radius.

When our anchor will be assembled, check if it will turn itself in the initial penetration position. If not, you will have to change the BSH to one with a bigger radius..

Good luck for the construction

A.L.
(*) BSH = Big Stupid Hook

I think I'm going to go with the flat version. I think the 'hoop' is correct for that one. The concept is essentially the same as the Danforth / Fortress anchors, in that they too have flat flukes with a reinforcer flange. The hoop idea is that used by the Bugel, of course, and it is a simpler idea than the hinge used on the Danforth / Fortress. A big drawback to the Danforth / Fortress concept is the fact that you can jam a stone or shell between the flukes and foul the anchor.

[Ancora Latina]

Originally Posted by BigCat

The hoop idea is that used by the Bugel, of course, and it is a simpler idea than the hinge used on the Danforth / Fortress.

Nobody is perfect!..

The BSH has also its drawback - "Invented" by Peter Bruce in 1973, Bruce has never used it!..
- The BSH will reduce the penetration
- will add more weight at the back part of the Fluke (where it is the least needed)
- Will keep weed and mud when breaking the anchor out..

If you search a little bit more, you can find a desing where you doesn't need to have a BSH..

Good Luke in your search!

[BigCat]

Originally Posted by Ancora Latina

Nobody is perfect!..

The BSH has also its drawback - "Invented" by Peter Bruce in 1973, Bruce has never used it!..
- The BSH will reduce the penetration
- will add more weight at the back part of the Fluke (where it is the least needed)
- Will keep weed and mud when breaking the anchor out..

If you search a little bit more, you can find a desing where you doesn't need to have a BSH..

Good Luke in your search!

There are a couple of new anchors being discussed in this site, one of which seems to be a spade knock-off, and the other which seems rather like an inverted delta, but I think I'll stick to modifying the Bugel, because it is so easy to make.

[BigCat]

Borrowing from the Bugel and the Bruce-an even simpler anchor to make that picks up less mud when brought aboard, as suggested by Ancora Latina-Consists of 2 pieces of flat plate, cut with a torch and welded together.

[Ancora Latina]

Originally Posted by BigCat

Consists of 2 pieces of flat plate, cut with a torch and welded together.

Hi Tim,

By experience, I can tell you that anchors are not so easy to design.

The drawing you shown, could work. you should try it! but I believe that if it falls down on the sea bed in an inverted position (resting on the shank) it will stay on the shank and will not digging in at all.

To have an anchor of that design that will dig in, you may have to add:
- either a lot of weight at the tip, like the Spade design
- or a BSH, like the Bruce patent, the Bügel, the Rocna, the Supreme or the Sarca.

Consider also that the holding coefficient of a "spoon" shape is by far more efficient that the one of a flat fluke.

[BigCat]

Originally Posted by Ancora Latina

Hi Tim,

By experience, I can tell you that anchors are not so easy to design.

The drawing you shown, could work. you should try it! but I believe that if it falls down on the sea bed in an inverted position (resting on the shank) it will stay on the shank and will not digging in at all.

To have an anchor of that design that will dig in, you may have to add:
- either a lot of weight at the tip, like the Spade design
- or a BSH, like the Bruce patent, the Bügel, the Rocna, the Supreme or the Sarca.

Consider also that the holding coefficient of a "spoon" shape is by far more efficient that the one of a flat fluke.

Hi, AL - the key points are at the same location as the Bugel, that is the fluke tip, the attachment point for the shank, and the top of the shank is at the same point as the top of the hoop on the Bugel. So, I am not inventing any proportions or angles, just modifying the structure somewhat. I realize that the convex shape is usually considered to be best, but the Fortress has huge holding power with completely flat flukes, so I am not convinced that popular wisdom is right. I think fluke area is the main determinant of holding power, since you can't beat a Fortress for holding power. --It would be easy to add a hoop, if needed, and the modified shank would reinforce it, because the top of the arc of the hoop would intersect with the knuckle of the shank.

[Therapy]

If the Fortress is used so much as a fall back/secondary/emergency anchor by so many (as I read) then why is it not a primary?

[Ancora Latina]

Originally Posted by BigCat

Hi, AL - I am not convinced that popular wisdom is right. I think fluke area is the main determinant of holding power, since you can't beat a Fortress for holding power.

Hi Tim,

They are wisdoms which are very well accepted, like anchors developed to hold oil rigs in the North Sea or holding of « aluminum » anchors...

In Tests, holding of anchors is always related to weight. If you consider that density of aluminum is about three times the one of steel, then for the same weight, the holding surface area of one aluminum anchor would be about three times bigger than the surface area of a steel anchor.

It would be very interesting to compare two similar anchors ( same type - same surface area)... and I’m not sure the holding difference will be that big?