Why Are Next-Gen Anchors Considered 'Better' ?

[motion30]

That works for wood, but how does welding 3 pieces of metal together make it stronger then a single thicker piece of stock? cheaper maybe yes

[noelex 77]

Originally Posted by hpeer

This would seem to imply that the Spade shaft is thicker (vs. higher) than other shafts. But there is no mention of that I could find. Looking at comparative photos this seems to be true but I can't tell for sure.

If not, then the Spade shaft would seem to be weaker than comparable anchors.

The Spade shaft is hollow, so it is thicker than most other anchors that have a solid shank.
Presumably it is correctly engineered. I have never heard of one bending. They did have some corrosion problems, at the base, with some of the early ones, but they replaced those at no charge, which is nice.

[noelex 77]

Originally Posted by motion30

That works for wood, but how does welding 3 pieces of metal together make it stronger then a single thicker piece of stock? cheaper maybe yes

Resistance to bending increases dramatically as the thickness is increased. This applies even if a lot material in the middle is removed. (sorry engineers I am tiring to keep it simple) This is the principal behind an” I” beam, or cored fiberglass structure.
So fabricating multiple pieces and making the shank hollow Spade have achieved a shank that will resist bending far more than the same weight in a solid structure. Shank weight is detrimental to anchor performance so a strong, but lightweight shank is helpful.
The hollow construction would be considerably more expensive to make than a solid structure of similar strength, despite the smaller amount of metal used.

[SailFastTri]

The cross section of the Spade shank is triangular. That's the most rigid geometric shape. Very strong.

As for the Aluminum Spade, we had some problems getting it to penetrate hard bottoms. Sold it. Have heard the steel Spade is much better at setting. Regardless of the material, once set they hold VERY well.

[psneeld]

Originally Posted by noelex 77

Resistance to bending increases dramatically as the thickness is increased. This applies even if a lot material in the middle is removed. (sorry engineers I am tiring to keep it simple) This is the principal behind an” I” beam, or cored fiberglass structure.
So fabricating multiple pieces and making the shank hollow Spade have achieved a shank that will resist bending far more than the same weight in a solid structure. Shank weight is detrimental to anchor performance so a strong, but lightweight shank is helpful.
The hollow construction would be considerably more expensive to make than a solid structure of similar strength, despite the smaller amount of metal used.

Why is shank weight detrimental?

[noelex 77]

Originally Posted by psneeld

Why is shank weight detrimental?

The lower the centre of gravity the better. Ideally the weight is concentrated in the fluke particularly the tip. The Spade design depends on keeping the weight in this area to achieve the correct orientation.
The other benefit of a lighter shank is that it allows for a larger fluke area for the same overall anchor weight.
Holding power increases as the fluke area rises.

[YOGAO]

Originally Posted by psneeld

Why is shank weight detrimental?

It is better to have the weight in the flukes than in the shank. Among other things, it makes it more likely that if the anchor does break free (due to a wind or current shift, for example), the anchor will re-orient itself to the new position and re-set.

[psneeld]

Originally Posted by noelex 77

The lower the centre of gravity the better. Ideally the weight is concentrated in the fluke particularly the tip. The Spade design depends on keeping the weight in this area to achieve the correct orientation.
The other benefit of a lighter shank is that it allows for a larger fluke area for the same overall anchor weight.
Holding power increases as the fluke area rises.

While I sort of agree in theory...I mostly don't... at least with the designs I'm usd to.

...at least to the point where the weight difference in a solid vesus hollow shaft would have to be enormous...just did some dragging tests on an old Delta of mine and doubling or halving the shaft weight wouldn't have changed a thing unless you were anchoring something akin to jello.

On a danforth style anchor...I doubt shft weight has any influence of setting except for maybe the heavier the better.

[YOGAO]

Originally Posted by psneeld

While I sort of agree in theory...I mostly don't... at least with the designs I'm usd to.

...at least to the point where the weight difference in a solid vesus hollow shaft would have to be enormous...just did some dragging tests on an old Delta of mine and doubling or halving the shaft weight wouldn't have changed a thing unless you were anchoring something akin to jello.

On a danforth style anchor...I doubt shft weight has any influence of setting except for maybe the heavier the better.

You are kind of missing the forest for the trees here.

I think the fundamental design brief for "nex-gen" anchors is how to have an anchor that orients itself for quick and stable setting AND re-setting along with a substantial fluke area for good holding once set.

The Spade accomplishes this by engineering for a heavy tip and the concave fluke. The hoop style basically uses the hoop and shank design to help the orientation and a larger area fluke.

This is a different philosophy than either the Delta, Danforth or CQR.

[GordMay]

Originally Posted by psneeld

... just did some dragging tests on an old Delta of mine and doubling or halving the shaft weight wouldn't have changed a thing unless you were anchoring something akin to jello ...

By what means did you reach that conclusion?

[psneeld]

Originally Posted by GordMay

By what means did you reach that conclusion?

Just old fasion eyeballing from a backyard boatyard mech...if the density of the bottom can support equally all parts of the anchor...it's more shape, pull and overall weight making the difference...not the center of gravity moving an inch or so because the shaved a few pounds out of the shank.

After years of looking at anchoring tests where so many conflict with each other and are done under conditions that no where resemble actual anchoring conditions...I equate them to the butter/margarine- which one's better for you argument.

[Fortress]

Originally Posted by psneeld

On a danforth style anchor...I doubt shft weight has any influence of setting except for maybe the heavier the better.

Sharpness is a huge factor in allowing the anchor to penetrate deeply into a sea bottom. This is why we sharpen the flukes and taper the shank, as evidenced by the image below.

Obviously, the deeper an anchor can penetrate into a sea bottom, the greater the resistance will be to it coming back out.

Safe anchoring,
Brian

[Cormorant]

FWIW, I've been comparison shopping online for the Manson Supreme 25, and overtons.com is currently offering it at $199.99, plus $17 shipping. Best price out there, as far as I can tell. Took a bit of drilling down to find that -- it doesn't show up in Google Shopping results.

Overton's price for the Manson 35 ($379.99 + $19 shipping) is not the best out there, though. . . . I think imarineusa.com might be best at $340.70 plus $9.95 shipping.

I may buy the 25 this year . . . but in my flinty cheapskate heart, I still hope to just find one while diving. . . . even if I have to detach it from some pesky chain.

[psneeld]

Originally Posted by YOGAO

You are kind of missing the forest for the trees here.

I think the fundamental design brief for "nex-gen" anchors is how to have an anchor that orients itself for quick and stable setting AND re-setting along with a substantial fluke area for good holding once set.

The Spade accomplishes this by engineering for a heavy tip and the concave fluke. The hoop style basically uses the hoop and shank design to help the orientation and a larger area fluke.

This is a different philosophy than either the Delta, Danforth or CQR.

One might say the same for your opinion....you don't think the designers of the Delta, Danforth or CQR had the same requirements?

I would argue the danforth should easily win hands down in all accounts except where a sharp veer puts it in an unusual requirement...and I HATE danforths...

[goboatingnow]

After years of looking at anchoring tests where so many conflict with each other and are done under conditions that no where resemble actual anchoring conditions...I equate them to the butter/margarine- which one's better for you argument

I dont agree, whiel such tests have a degree of subjectivity and and difficult to cross compare, you can extract overall results. Its is clear that the common and successful next-gen anchors are better then older variants I would out it as ( spade, rocna, manson), ( delta) , ( fortress) ( then CQR, etc) ( and bruce).

Dave