Open Source Anchor Project

[Jimbo485]

Nice idea but what about the weight of 2 "extra" flukes? And how they will impede rather than assist deep penetration?

Why not go for 2 flukes rather than 3?

Now, how about cutting a strip down the centre of the fluke so that a hinged shank can pass through the fluke and thus we have 1 fluke rather than 2? The single fluke can flop from one side of the shank to the other.

Hey, I think I have seen this type of anchor before. Called a Dan Go Forth?

Let's make it out of alloy and call it a Castle!

I like Delancey's design a page or two back much more because the use of heavy plate was more efficient.

Great to see the ideas flowing.

[Hydra]

Originally Posted by Cheechako

* The base/center of the fluke assembly would l ikely be somewhat smaller than shown and cupped in the forming process rather than flat.
*Each fluke would have some sort of gussett welded to the shank on centerline. (not shown)
* the whole Fluke "pan" could be formed on a Cincinatti 32" hydroformer one piece with no welds... including the cupping and bent ridge in the flukes.
* After forming the shape could be cut by laser or similar allowing changing the fluke shape away from a true triangle... maybe each point on the "base" triangle would have a mini fluke... a bit like the tips of a Bruce...or...?

Your model is impressive. The base could even be formed in the old-fashioned way, by forging on an anvil. I think the design could be improved by cutting an opening in each fluke, to make setting faster and reduce clogging with mud.

However, I see 2 problems:

- the uppermost fluke would oppose to the anchor diving in the bottom;
- when the anchor is set in a shallow layer of sand over hard pan, one fluke would remain exposed and susceptible of being caught by the rode at the turning of the tide, just like a fisherman's anchor or a Northill.

Alain

[avb3]

A lot of great ideas for an anchor setting.

One needs to also consider how will it react to breaking loose. Was that part of the downfall of the Bulwagga, apart from being plain ugly?

[Cheechako]

I'm now thinking that the triangle approach is not needed. I want the base to be spherical or cupped to some extent, why not the flukes also? Maybe more rounded tips like a Bruce anchor. Looking for a ping pong ball to make another model........
Yes I agree about one fluke catching the rode... it's an issue for sure.... and probably why tri sided anchors arent produced.
The Danforth is a two sided anchor, but doesnt reset well due to the pivoting flukes on the shank. (flukes just skate along the bottom when trying to reset) If it didnt pivot it might be better but then would only be a one sided anchor! If we put flukes on a non pivoting shank on boat sides of a danforth.... well... we're getting pretty close to a Northill I suppose. I wonder if a Danforth style with the shank non pivoting and a roll bar opposite might be a very good anchor...?

[Hydra]

Originally Posted by Cheechako

I wonder if a Danforth style with the shank non pivoting and a roll bar opposite might be a very good anchor...?

This looks similar to a Knox anchor!

Alain

[Delancey]

I played around with an equalateral triangle and even a circle, came up with a couple different neato ways to have a pivoting shank that would lock into position. All the best intentions don't change the fact that if it lands upside down, it's going to stay that way. There's no way around it. Back to the roll bar.

[Delancey]

Ok, so we have a general concept on how we are going to make our shank, our shank/fluke connection and our roll bar. Next we need to really nail down our fluke design. The three concepts I have shown previously were just sort of knocked out in an afternoon and aren’t really worth much at this point, we really need to look closer at the function of the fluke. To be fair we should take a look at a convex shape in addition to the other three and maybe we figure we have a Danforth type as a second anchor and can skip the mud fluke for now. You tell me.

Before we get started we need to go back to the original Bruce Patent and while we are at it, we can take a look at culture and how it influences design. I already mentioned the Japanese VS Western approach to hand saw design. There are other examples as well. Everyone likes Scandinavian interior design right? Bright, cheerful, full of light. When you think about how dark and miserable it is up north half the year and the fact that alcoholism and suicide rates are as high as they are it kinda makes sense I suppose.

What about anchors? I mentioned how very Germanesque the Bugel is with its brutal elegance and single-minded minimalism. I bet I could show the Bugel to a good designer but who knows nothing of anchors and they could guess what country it came from. What about the Spade? Sensuous but complicated? It came from France?

So what about Peter Bruce and the original “new generation” anchor? When I first looked at the Patent drawings I knew I had seen these fluke shapes before but couldn’t put my finger on it. They are very specific shapes. I was struck but how unlike any anchor I have ever seen they looked and I was totally intrigued. I searched for background but could find very little bio for the man himself. I knew the end use of the Bruce Claw was for offshore oil platforms but didn’t know if that where he started out.

All I could do is think about the time period and it hit me very quickly. In 1969, man first stepped foot on the moon. In 1970, the year of Peter Bruce’s original filing for a British Patent, the world’s first Super Sonic Transport took flight, the Concorde - Wikipedia, the free encyclopedia . Just so happens the Concorde was designed and built by a French and British partnership that relied on Rolls Royce engines that would have been built in England using complex shaped turbine blades cast in metal using the same basic techniques as the Bruce anchors.

The shape you see in the plan view is called an Ogive - Wikipedia, the free encyclopedia and has its roots in Architecture where you know it as a Gothic arch. It is also used in the design of things like bullets and rocket nose cones. The design of the world’s first supersonic airplane, the Bell X-1 - Wikipedia, the free encyclopedia , is often referred to as a bullet with wings. In fact its shape was derived from the design of the .50 caliber bullet which was known to be stable in trans-sonic flight.

Now here’s the thing, design rarely if ever happens in a true vacuum. You tell me if I am wrong but it looks to me like Peter Bruce, when he set out to reimagine the anchor with a totally new and original design, didn’t at least borrow from these sound-barrier penetrating shapes for inspiration. The fact that Mr. Bruce ultimately turned his back on the single fluke, compound curved, crooked shank, roll bar anchor described in his original Patent and instead evolved his concepts into what we know as the Bruce Claw is neither here nor there.

The Bruce Claw is a truly great anchor design as is attested by its many ardent fans. It might not be the best anchor for all people all the time, but it certainly has its place. When it does set as it’s supposed to and it stays set, it is everything you want an anchor to be. Maybe hard packed sand isn’t its forte, but without knowing Peter Bruce’s full story or what his intentions were, we can’t really say if his design makes or misses his mark.

What will the OSA design say about us as designers? Well hopefully it will say we give a crap about the environment and are willing to do something about it, even if only in a small way. Hopefully it will say we value the individual more than a corporation, that we value relationships with people in our own communities more than relationships with online vendors selling us products from China. Hopefully it will say we value the free exchange of information and an open society that supports it. Lastly, hopefully it will say that we, as sailors, value learning the skills and the knowledge necessary to be as self-sufficient as possible, right down to making our own anchor.

So what’s next in the design process? We are going to break down the fluke function within the context of our shank and roll bar and put together our rough design draft. After that we are going to do Finite element method - Wikipedia, the free encyclopedia of our individual components to determine whether our general assumptions about material thickness and connection strengths were correct. Then it’s back to drawing to massage the details and make it all work based on the FEA to finish our design draft. One that’s completed we can actually start making mockups and do some testing.

That said, now is a good time for any dissenters to speak up. If you really don’t like the straight Bugel-styled shank for example, a change to a crooked one is going to affect the roll bar, which in turn affects the fluke. They all relate with each other and at a certain point in the process you need to commit to certain things before you can move forward. Here’s your chance to help make that decision.

[Delancey]

Couple honorable mentions from the annals of anchor design I have run across.

I really like the Danforth type. Just because something has a rudimentary function doesn't mean it can't be nice looking. I like the salient geometry of the fluke tips BTW. Give it a fixed shank and a roll bar out on the horns of the fluke and you've got a new gen anchor. Makes me think of the Mantus a little bit, how the roll bar projects past the fluke.

As for the other one, a modern take on an old concept, sometimes you just have to do the best you can with what you have on hand. Nothin wrong with that unless it lands upside down, maybe the bouyancy of the wood stock stops that from happening, I don't know. There ya go nimblemotors. There's your ultra-light-weight anchor inspiration.

[noelex 77]

Originally Posted by Delancey

I really like the Danforth type. Just because something has a rudimentary function doesn't mean it can't be nice looking.

The Jambo is an interesting variation.

Beautifully made, rivals the Ultra for the "Sexy anchor award", but not much fluke area

[Delancey]

Originally Posted by noelex 77

The Jambo is an interesting variation.

Beautifully made, rivals the Ultra for the "Sexy anchor award", but not much fluke area

Nice anchor, sexy and a little cruel looking. Austrian design, go figure. Cast steel parts.

The Jambo-Anchor

[noelex 77]

Originally Posted by Delancey

Nice anchor, sexy and a little cruel looking. Austrian design, go figure. Cast steel parts.

You are a sick, sick man, just like me

It comes in galvanised and stainless steel. The stainless version is way sexier, but I am not sure the fish appreciate the difference.

[Delancey]

Originally Posted by noelex 77

You are a sick, sick man, just like me

It comes in galvanised and stainless steel. The stainless version is way sexier, but I am not sure the fish appreciate the difference.

Austrian, sexy, and a little cruel. Reminds me of a girl I know. Just sayin.

If you were a clam buried in the sand about to get crushed by a setting anchor which one would you choose? Do we need to add another design criterea? No reason our OSA can't be good looking to boot.

Sexy usually means curves. Most of the current new gens tend to favor straight line geometry on the edges but three points and a wood batten gets you a curved line, our guy on the beach can handle that.

We can see with the Bugel that that scalloped edge actually has a purpose. You can do the same thing with straight lines as most of the new gens do but curves are sexy, no denying it.

[noelex 77]

Here is the Galvanised version. In the flesh the stainless model looks, well, more like that girlfriend

[Delancey]

Here's a couple old school Ogive shapes that predate supersonic flight by a few millennium. I think these lend some street-cred to the shovel shaped mud fluke or the curvy point I gave to the Bugel style fluke.

[Delancey]

This from a different thread posted by cwyckham-

"And to the other...yep! By the time I'm done with shipping and taxes...blah blah blah...my 88lb Rocna was about $1500. Sometimes I think dropping a 50 gallon drum of concrete off the side with my crane would have been better!! ;-)"

Seveteen bucks a pound? For galvanized steel? 1,700% mark-up over the going rate for steel as a commodity? Yes, of course that includes the design, the labor, the galvanizing, the oil used in shipping the thing around, the profit. But come on!

Remember that chain, which is just as important as your anchor, has all those associated costs is only at around a 500% mark up. Given it has moving parts you could argue chain is more complex. It's manufacturing certainly is complex. Makes cutting and welding plate or casting look pretty simple. Cool chain making video.

http://www.youtube.com/watch?v=Pi-WXD1I3H8