- Out of these four tools, only the "chisel" has been concieved for penetration.. ask the Carpenter.!!..
- The penetrating edge has to be as sharp as possible...
2 - Pressure on the tool:
More the pressure, easier will be the penetration... Obvious...
Look at the percentage weight on the tip of some classical anchors:
(from Practical Boat Owner, page 80 n° 391 - July 1999)
The anchor having both the right penetrating 'chisel like' angle and the heaviest tip will have the maximum chance of penetrating, even in difficult sea bottoms such as hard sand, coral and weed…
Holding is related to three factors:
- Holding surface area
1° - STABILITY:
In this regard, the conclusion of John Knox (P. 81 - PBO n° 427 July 2002) confirms completely my own observations as well as the results of the tests done by the French "Voiles Magazine":
- Generaly speaking , ALL HINGED ANCHORS are unstable (Plow anchors, fluke anchors…) Under strong pulls, they corkscrew and break free.. (and I can explain why..)
-Stable anchors of the new generation could slightly drag under strong wind gusts, but they keep a constant high holding and they will not break free suddenly... (Very SAFE behaviour)
Holding surface: Try to pull one square meter of steel on the bottom, this is quite easy.. Now bury this plate of steel in the bottom an try again.. Holding has nearly no relation with the weight, but is related to:
- The surface area perpendicular with the direction of the pull..
The shape of this surface
- a "wing" shape has an "holding" coeficient of 0.1
- a "chevron" shape has an "holding" coeficient of 0.5
- a "flat" shape has an "holding" coeficient of 1.1
- a "concave" shape has an "holding" coeficient of 1.7
Or in other words, a surface with a "Chevron" shape must be more than three times the area of a surface with a concave shape to have the same holding.
This may seem simple, but in addition:
- A good anchor must hold regardless of wind and /or current change of direction.
- lt sould not have the possibility to become tangled with the anchoring rode.
- lt should not require any specific anchoring technic.
- lt should fit snugly on a the bow roller
- Used with an electric windlass, it should be self launching and retrieving .
- lt should be very strong
As you will have noticed, I haven't mentioned any brand names . . . this will be YOUR responsibility..
If you assess all models, and can find one that has all the characteristics mentioned in the article, then you can be sure you have made a good choice.