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View Full Version : what do you guys think of these home made anchors?



Phillip Allen
04-13-2015, 12:05 PM
https://www.youtube.com/watch?v=D-QjaDoBy0o

Paul Pless
04-13-2015, 12:14 PM
modified bruce

paulf
04-13-2015, 12:21 PM
I've built a few, by the time you buy the materials and figure time in its a wash usually.

Captain Intrepid
04-13-2015, 12:31 PM
They look fine, but I wouldn't trust them for a serious application.

Paul Pless
04-13-2015, 12:33 PM
but I wouldn't trust them for a serious application.you mean like anchoring?

Phillip Allen
04-13-2015, 12:38 PM
They look fine, but I wouldn't trust them for a serious application.

do you think they're made differently than anchors you DO trust? (just asking)

Captain Intrepid
04-13-2015, 12:39 PM
you mean like anchoring?

On someone else's boat? :d

Captain Intrepid
04-13-2015, 12:46 PM
do you think they're made differently than anchors you DO trust? (just asking)

Aye. They lack the engineering, testing and certification for me to trust em.

If I'm putting tens or hundreds of thousands of dollars into a boat, saving a few hundred on the anchor by building an untested homemade design seems like an unnecessary risk. I wouldn't sew my own climbing harness for the same reason.

Phillip Allen
04-13-2015, 12:54 PM
Aye. They lack the engineering, testing and certification for me to trust em.

If I'm putting tens or hundreds of thousands of dollars into a boat, saving a few hundred on the anchor by building an untested homemade design seems like an unnecessary risk. I wouldn't sew my own climbing harness for the same reason.

I don't see where 'engineering' is missing... it may be good or it may be blue sky... but it's only a guess I think... testing? certification?

consider that 'engineering' in modern parlance, means creating something with the absolute minimum of cost and material

Paul Pless
04-13-2015, 01:05 PM
consider that 'engineering' in modern parlance, means creating something with the absolute minimum of cost and materiali admire your ability to just make up statements of non sequitur out of thin air

Bobcat
04-13-2015, 01:07 PM
Aye. They lack the engineering, testing and certification for me to trust em.

If I'm putting tens or hundreds of thousands of dollars into a boat, saving a few hundred on the anchor by building an untested homemade design seems like an unnecessary risk. I wouldn't sew my own climbing harness for the same reason.

Well put.

Won't make my own parachute either.

Modern anchors have a lot of testing

Captain Intrepid
04-13-2015, 01:07 PM
I don't see where 'engineering' is missing... it may be good or it may be blue sky... but it's only a guess I think... testing? certification?

consider that 'engineering' in modern parlance, means creating something with the absolute minimum of cost and material

The part where the anchors seem to be designed by guess and by God. It might work, it might not. I just ain't gonna trust it without extensive testing. By that time it would be cheaper and easier to use a tried and trusted design.

paulf
04-13-2015, 01:27 PM
The best anchors I've ever used, for multi hundreds of thousands of dollars worth of scientific gear, are railroad wheels at 3cents a pound and I engineered and built the bale and shackle.

However, it was tax payers property I was securing.

Peerie Maa
04-13-2015, 01:31 PM
Everything that they could do wrong they have done wrong. The shank is too thin. The edges that should cut into the soil are blunt. The dihedral of the palm is upside down. I doubt that they will self set, nor stay set if veered. Horrible.

Peerie Maa
04-13-2015, 01:33 PM
modified bruce

Nope. It misses all of the attributes that make a Bruce work.

John of Phoenix
04-13-2015, 01:34 PM
However, it was tax payers property I was securing.And the unlimited insurance policy that backs it. Try collecting a regular insurance claim after a homemade anchor (or whatever) fails.

Dave Hadfield
04-13-2015, 01:34 PM
Neville Shute, the author who was a very qualified aeronautical engineer, said, or repeated, "An engineer is someone who can build for a shilling what any dam fool can build for a pound."

I have sewn my own climbing harness. I'm still alive.

But... If I welded my own anchor, I'd test it first, as hard as I could, in a non-jeopardy situation. Like anchoring in a 40 kt wind and sea, and then running the engine full astern for 10 minutes. Then inspect the welds.

Only then would I sleep at night.

Dave

Captain Intrepid
04-13-2015, 01:37 PM
The best anchors I've ever used, for multi hundreds of thousands of dollars worth of scientific gear, are railroad wheels at 3cents a pound and I engineered and built the bale and shackle.

However, it was tax payers property I was securing.

And the bulk of the anchors I've used in my life have literally been concrete blocks, but different applications have different levels of engineering. It's easier to engineer an anchor that mostly depends on sheer weight.

Chris Coose
04-13-2015, 01:44 PM
Well put.

Won't make my own parachute either.



I wouldn't make my own condoms either. In days of old when they made anchors out of tons of iron they were also using goat bladders, sheep intestine for birth control. As the bulk got reduced they took more to sleek designs, therefore, specific testing.

Hwyl
04-13-2015, 01:48 PM
. Try collecting a regular insurance claim after a homemade anchor (or whatever) fails.

What John said, even retail knock offs won''t pass the insurance muster.

Chris Coose
04-13-2015, 01:55 PM
I love what lake boat guys keep stored for anchors, then take their occasional salt sea voyage and never think of the possibilities the ocean has to offer. My brother being one of them.

Kevin T
04-13-2015, 02:34 PM
This guy lives in Tulsa, building his own boat, that I am not sure he will ever get through town to water. I think the anchor is the least of his worries, and insurance really? If he can get out of his neighborhood and over to Pine street it is a straight shot to Catoosa. So maybe.

Man, what if after all of this building, he was unable to get the damn thing to water, YIKES!!

With respect to the anchor, I found it curious that the boat looks far from finished and he's mucking about building ground tackle. Priorities man, priorities!

Gerarddm
04-13-2015, 03:02 PM
I'd make my own grapple, maybe. That's it. Not an anchor.

Peerie Maa
04-13-2015, 03:21 PM
I'd make my own grapple, maybe. That's it. Not an anchor.

I made the anchor that I use on Peerie Maa. But I did research the ideal proportions first.
http://i408.photobucket.com/albums/pp164/peerie_maa/anchor.jpg

paulf
04-13-2015, 04:14 PM
A vessel anchor will not work for research deployments. There can be no scope i.e chain. The thing that holds so well is being silted in. Recovery is via acoustic release. The anchor remains on the bottom for deep deployments. Most deployments are of sub surface equipment with suspending sub surface pressure floats that keep the array suspended off the bottom.

For a vessel riding the surface swell and wind I agree, a tried and true design with lots of scope chain.

I didn't mean to introduce apples into an oranges conversation.

Phillip Allen
04-13-2015, 04:51 PM
how would your testing manifest itself?

The part where the anchors seem to be designed by guess and by God. It might work, it might not. I just ain't gonna trust it without extensive testing. By that time it would be cheaper and easier to use a tried and trusted design.

Phillip Allen
04-13-2015, 04:54 PM
Neville Shute, the author who was a very qualified aeronautical engineer, said, or repeated, "An engineer is someone who can build for a shilling what any dam fool can build for a pound."

I have sewn my own climbing harness. I'm still alive.

But... If I welded my own anchor, I'd test it first, as hard as I could, in a non-jeopardy situation. Like anchoring in a 40 kt wind and sea, and then running the engine full astern for 10 minutes. Then inspect the welds.

Only then would I sleep at night.

Dave
a start, but the stress I'm aware of are repeated 'jerks' over days and days

Phillip Allen
04-13-2015, 04:57 PM
I made the anchor that I use on Peerie Maa. But I did research the ideal proportions first.
http://i408.photobucket.com/albums/pp164/peerie_maa/anchor.jpg

so, this guy didn't research anything? I wouldn't know but I can ask him sometime

Paul Pless
04-13-2015, 05:03 PM
Its not so much the welds that are the worry; it whether the design holds and whether if it is twisted out does it reset.

Peerie Maa
04-13-2015, 05:04 PM
a start, but the stress I'm aware of are repeated 'jerks' over days and days

A well designed ancho will just set deeper under "repeated 'jerks'". Veer enough chain and the anchor will not be "Jerked" all that much as the spring rate of the rode absorbs the shocks.

Peerie Maa
04-13-2015, 05:13 PM
how would your testing manifest itself?

The accepted way to test an anchor is with a hydraulic jack pushing the tip of the palms and the shackle apart. I suspect that the shank of those anchors would buckle.

Phillip Allen
04-13-2015, 05:14 PM
A well designed ancho will just set deeper under "repeated 'jerks'". Veer enough chain and the anchor will not be "Jerked" all that much as the spring rate of the rode absorbs the shocks.
my thinking is not about rode or setting... it's about the welds and the necessary bi metallic nature of them

Peerie Maa
04-13-2015, 05:37 PM
my thinking is not about rode or setting... it's about the welds and the necessary bi metallic nature of them

See post #32

Old Dryfoot
04-13-2015, 07:08 PM
My inflatable used an anchor just like this one. Packing it in and out was never a problem. There were few times I had a tough time finding rocks though. . .
http://www.equinoxltd.com/images/products/medium/mfg131.jpg

Phillip Allen
04-13-2015, 07:16 PM
Here's a boat tour which might answer a question or two

https://www.youtube.com/watch?v=BeP0c5_pskA

Dannybb55
04-13-2015, 07:34 PM
Use long and heavy chain. A rode rider and a Luke as a bower. Keep the toy for picnics.

Dannybb55
04-13-2015, 07:36 PM
Does anyone know the difference between a CQR and a Danforth? CQRs were on Short flying boats, Danforths were for Convair Catalinas.

hokiefan
04-13-2015, 07:51 PM
I don't see where 'engineering' is missing... it may be good or it may be blue sky... but it's only a guess I think... testing? certification?

consider that 'engineering' in modern parlance, means creating something with the absolute minimum of cost and material

No, engineering is creating a design that you KNOW will work. By calculating and evaluating the stresses on every part to ensure it is absolutely strong enough. And testing and modifying if necessary the design to ensure it performs. For an anchor that means does it reliably set and then stay set when the boat swings. Or does it reset if it swings enough to pull out. "It looks like it will work" is not even close to engineering.

Cheers,

Bobby

Phillip Allen
04-13-2015, 08:00 PM
No, engineering is creating a design that you KNOW will work. By calculating and evaluating the stresses on every part to ensure it is absolutely strong enough. And testing and modifying if necessary the design to ensure it performs. For an anchor that means does it reliably set and then stay set when the boat swings. Or does it reset if it swings enough to pull out. "It looks like it will work" is not even close to engineering.

Cheers,

Bobby
feeling defensive, are we? :)

paulf
04-13-2015, 08:39 PM
Actually, look up Henri O Berteaux, Coastal and Oceanic Buoy Engineering. He fully discusses drag,bottom type, bottom yield and mooring components. No commercial anchor is best for all situations.
There is no "one size fits all". his calculations show what works for differing depth, current and bottom type. Its all a trade off.

Engineering does have a lot to do with it, so does experience and local knowledge. And with a boat you can anchor in the best conditions for your particular hook.

hokiefan
04-13-2015, 08:44 PM
feeling defensive, are we? :)

Not at all. But I know what engineering really is, and "it seems like it will work" isn't it. Despite the fact that engineers sometimes do that, it doesn't make it engineering.

Cheers,

Bobby

Paul Pless
04-13-2015, 08:52 PM
my thinking is not about rode or setting... it's about the welds and the necessary bi metallic nature of them

Why are welds necessarily bi metallic?

Phillip Allen
04-14-2015, 01:25 AM
Here's a boat tour which might answer a question or two

https://www.youtube.com/watch?v=BeP0c5_pskA

did anyone look at this... it's pretty interesting to me

Tom Hunter
04-14-2015, 06:48 AM
In the video Phillip posted #45 he shows the anchors and says they can be taken apart. There is a single bolt holding the two pieces together and it looks pretty light. I predict he will upgrade his anchors at some point in the future. Hopefully when it comes apart its not a crisis.

Canoez
04-14-2015, 07:26 AM
Not at all. But I know what engineering really is, and "it seems like it will work" isn't it. Despite the fact that engineers sometimes do that, it doesn't make it engineering.

Cheers,

Bobby

^^^^
THIS!!!

Engineering is about having objective data from the testing of the materials you use and knowing how the forces will be applied and how the environment will attack the materials. An engineer would have specifications and design goals with an appropriate factor of safety in a situation where life and limb are at stake. Because life and limb are at stake, validation testing of the finished product should be done. Plus, I'm sure the insurance companies have their own hoops for the fabricators of anchors to jump through.

Canoeyawl
04-14-2015, 11:13 AM
Why are welds necessarily bi metallic?

I had to look it up... Certainly we are not talking about a thermostat here.
There are several interpretations but the most likely one is
"Binary alloy (http://en.m.wikipedia.org/wiki/Bimetallic), in metallurgy, a mixture of two metals"
which would be poor welding practice for most applications.

Phillip Allen
04-14-2015, 12:06 PM
In the video Phillip posted #45 he shows the anchors and says they can be taken apart. There is a single bolt holding the two pieces together and it looks pretty light. I predict he will upgrade his anchors at some point in the future. Hopefully when it comes apart its not a crisis.

I wondered about that but in an old fisherman, there's no bolt at all... no one is condemning those... ?

the bolt only holds it together until it takes a strain and after that is undeeded

Phillip Allen
04-14-2015, 12:10 PM
Why are welds necessarily bi metallic?

the welding rod/wire is not the same as the parent material... simple and it's salt water in the gulf

Paul Pless
04-14-2015, 12:14 PM
the welding rod/wire is not the same as the parent material... simple and it's salt water in the gulfwhat is it that you think welding sticks are made out of?

Captain Intrepid
04-14-2015, 12:20 PM
In the video Phillip posted #45 he shows the anchors and says they can be taken apart. There is a single bolt holding the two pieces together and it looks pretty light. I predict he will upgrade his anchors at some point in the future. Hopefully when it comes apart its not a crisis.

That's one part I'm not so concerned about. The shank and it's hole are tapered, so they tighten together when a strain come on from the rode. It's the general geometry and strength of the anchor I would be concerned about.

Phillip Allen
04-14-2015, 12:48 PM
what is it that you think welding sticks are made out of?

various alloys, Doctor Paul

slug
04-14-2015, 12:49 PM
Everything that they could do wrong they have done wrong. The shank is too thin. The edges that should cut into the soil are blunt. The dihedral of the palm is upside down. I doubt that they will self set, nor stay set if veered. Horrible.


Yes...the edges of the fluke must be sharp.

the difference between a " real " correctly engineered and built anchor is obviuos when you purchase a cheap knock off.

i recently bought a cheap...half price...... chinese 50 kg Bruce to keep as a spare incase I loose my Bruce. The chinese bruce weighs 50 kg , but the rest is junk, right down to the blunt leading edges.

beware of junk

Peerie Maa
04-14-2015, 12:51 PM
Because life and limb are at stake, validation testing of the finished product should be done. Plus, I'm sure the insurance companies have their own hoops for the fabricators of anchors to jump through.

They certaioly do: http://www1.veristar.com/veristar/bvrules/D_4_s1_1_6.htm

My worry is that if an anchor is built out of under-thickness plate, it may pass a test based on its weight, but the area of the fluke may grab so much mud that it will overload it in service.

Phillip Allen
04-14-2015, 12:52 PM
well, this doesn't say much about home made boats which haven't been tested professionally and certified

Canoez
04-14-2015, 12:56 PM
well, this doesn't say much about home made boats which haven't been tested professionally and certified

No, it doesn't. Which is why home-built boats can be difficult to sell and insure.

You can build them yourself to a professional design with listed scantlings and best methods. If you do, you'll likely have a boat that will pass the required inspections. If you try to "improve" the design without consultation with the designer or NA, you may be making a mess.

Captain Intrepid
04-14-2015, 01:06 PM
well, this doesn't say much about home made boats which haven't been tested professionally and certified

And that would be one reason why most serious sailors are naturally very conservative about all things boat related. :) What's the first thing anyone hears when they come here with a post about a wonderful deal on a boat they've found? Get it surveyed by a professional.

Canoez
04-14-2015, 01:07 PM
Yeah, not an anchor, but turn the boat into an artificial reef.

Just because the guy is a good welder doesn't make the engineering design work.

Breakaway
04-14-2015, 01:08 PM
http://forum.woodenboat.com/images/misc/quote_icon.png Originally Posted by Canoez http://forum.woodenboat.com/images/buttons/viewpost-right.png (http://forum.woodenboat.com/showthread.php?p=4511289#post4511289)

Because life and limb are at stake, validation testing of the finished product should be done. Plus, I'm sure the insurance companies have their own hoops for the fabricators of anchors to jump through.



They certaioly do: http://www1.veristar.com/veristar/bv...D_4_s1_1_6.htm (http://www1.veristar.com/veristar/bvrules/D_4_s1_1_6.htm)


That's for ships. There are no certifications or design and/or material requirements for anchors for recreational craft, at least not in North America.

Kevin

Peerie Maa
04-14-2015, 01:38 PM
That's for ships. There are no certifications or design and/or material requirements for anchors for recreational craft, at least not in North America.

Kevin

However if there were, those are the standards I would expect to be applied.

As it is it is very much caveat emptor then.

Breakaway
04-14-2015, 02:22 PM
However if there were, those are the standards I would expect to be applied.

I don't disagree, Nick.

There are a lot of posts on this thread implying that these guys anchors are wrong because they don't meet the established principles of regulation or insurance critieria. There are none of the above. So, while this anchor may be "wrong"--there is no official body or organization to say so.

Kevin

Captain Intrepid
04-14-2015, 02:28 PM
I don't disagree, Nick.

There are a lot of posts on this thread implying that these guys anchors are wrong because they don't meet the established principles of regulation or insurance critieria. There are none of the above. So, while this anchor may be "wrong"--there is no official body or organization to say so.

Kevin

Even when standards are not legally required, they do give us an excellent place to start for determining best practices.

slug
04-14-2015, 02:47 PM
My chains, shackles and anchor come with certificates. ive never been asked by the Insurance company to produce these certificates, but if I had a accident they might want to know what I had for ground tackle.

Any incorrect seamanship , equipment. or preparation is considered negligence by insurance companies.

If you would like to use home made stuff , you might ask your insurance company.

Peerie Maa
04-14-2015, 02:53 PM
I don't disagree, Nick.

There are a lot of posts on this thread implying that these guys anchors are wrong because they don't meet the established principles of regulation or insurance critieria. There are none of the above. So, while this anchor may be "wrong"--there is no official body or organization to say so.

Kevin

True. It gets interesting when people try to innovate for one reason or another. The standard for a Fishermans anchor that I posted is the result of trial through the centuries, plus an understanding of basic geometry. I went for a job interview with Bruce Anchors, so I know something of the research and engineering and testing that went into the design and development of that product. A lot of the single fluke anchors marketed since will have been an attempt to get around Mr Brice's patents.

Now I mentioned in an earlier post that I remade the anchor that I use with Peerie Maa. I reworked an anchor built by a metal worker who based his design on this
http://www.jonlansberg.com/Illustrations/FouledAnchor2.jpg
The arms were too long, the palms thick, blunt and too small, the stock was too short and too far down the shank.
So I cut it up, fired up the forge and reworked the components so that I could weld them back up to the proven proportions posted above, with the spare metal from the arms reinforcing and adding weight to the crown.
That was a classic case of a welder making up an anchor that to their untutored eye looked right, but was totally wrong. I fear that is what we have been shown in the OP.

jclays
04-14-2015, 02:59 PM
Looks like the newer spade style. Like my original Bruce.

Phillip Allen
04-14-2015, 03:03 PM
I don't disagree, Nick.

There are a lot of posts on this thread implying that these guys anchors are wrong because they don't meet the established principles of regulation or insurance critieria. There are none of the above. So, while this anchor may be "wrong"--there is no official body or organization to say so.

Kevin

I used to sell guns... it is a fact that everyone wants to be an authority on guns (anchors in this case) and once anything is repeated once and they've not been checked... it becomes truth graven in stone... just part of being human

Phillip Allen
04-14-2015, 03:06 PM
Even when standards are not legally required, they do give us an excellent place to start for determining best practices.

some of those standards are simply proprietary... it's about marketing... everyone is trying to make a living and you can't get after them for that... that's how we get sham wows

Canoez
04-14-2015, 03:07 PM
Phillip - think about it like building codes. They exist for a reason. It gives safe, established rules for putting up buildings.

But be realistic - you sold guns. Could you design the mechanisms, select the appropriate alloys and the fit and tolerances to make a firearm? When reloading you follow established guides, no?

Captain Intrepid
04-14-2015, 03:07 PM
I used to sell guns... it is a fact that everyone wants to be an authority on guns (anchors in this case) and once anything is repeated once and they've not been checked... it becomes truth graven in stone... just part of being human

Hardly. I base my reservations on the fact that I am not an authority on anchors. I gladly defer to those who are.

Peerie Maa
04-14-2015, 03:13 PM
Looks like the newer spade style. Like my original Bruce.


Nope. It misses all of the attributes that make a Bruce work.

It is more like a bad cross between a Bruce and a Lewmar Delta (with the dihedral reversed)http://www.petersmith.net.nz/boat-anchors/images/old-gen-anchor-delta.jpg

The Lewmar Delta is a CQR without the hinge.

Captain Intrepid
04-14-2015, 03:13 PM
some of those standards are simply proprietary... it's about marketing... everyone is trying to make a living and you can't get after them for that... that's how we get sham wows

Bull.

In the marine industry we often say that regulations are written in blood. Do you know what that means?

Phillip Allen
04-14-2015, 03:15 PM
Phillip - think about it like building codes. They exist for a reason. It gives safe, established rules for putting up buildings.

But be realistic - you sold guns. Could you design the mechanisms, select the appropriate alloys and the fit and tolerances to make a firearm? When reloading you follow established guides, no?

I stay in the book... one reason and probably the best, I cannot improve on it and to try is to waste energy and time... it makes a hole in paper and that's all that's required... don't get silly
there was one instance where a product hit the market before the data did. (it was a bullet that I bought a package of) so I called the lab at the manufacturer... got the data over the phone and double checked it. when I tried it out, I fired a few rounds and pulled the rest down... way too damn hot. Hot, however, is what a lot of customers want... not me. if I want a hotter round, I'll get a hotter cartridge... just not a NASCR fan at all

Canoez
04-14-2015, 03:18 PM
Well, that book was established by design, research and testing. Same thing should be true of the anchor if you're going to depend on it.

Would you want to use climbing or arresting gear for a design that hadn't been tested?

Peerie Maa
04-14-2015, 03:18 PM
I used to sell guns... it is a fact that everyone wants to be an authority on guns (anchors in this case) and once anything is repeated once and they've not been checked... it becomes truth graven in stone... just part of being human

OK, you know enough about guns to sell them. Do you know enough about guns to specify the thickness of metal in the chamber walls? Would you fire a gun made by an amateur that looked something like, but was not actually made to any reliable gunsmiths drawings or steel specifications?

cross post with Canoez

Phillip Allen
04-14-2015, 03:19 PM
OK, you know enough about guns to sell them. Do you know enough about guns to specify the thickness of metal in the chamber walls? Would you fire a gun made by an amateur that looked something like, but was not actually made to any reliable gunsmiths drawings or steel specifications?

I might fire a gun made by an amateur... with a long string and an overcharge

Paul G.
04-14-2015, 03:21 PM
If you make an anchor heavy enough or dont demand too much it will work everytime, but if you rely on a 20kg anchor to hold a 5 ton boat in a blow then one would hope the anchor is designed and tested appropriately.

Peerie Maa
04-14-2015, 03:26 PM
I might fire a gun made by an amateur... with a long string and an overcharge

Sencible enough, but would you sleep at night on a boat in a tidal estuary hanging onto a hook that was made by a welder without any plans or any clear idea of what makes anchors work?

Phillip Allen
04-14-2015, 03:29 PM
Sencible enough, but would you sleep at night on a boat in a tidal estuary hanging onto a hook that was made by a welder without any plans or any clear idea of what makes anchors work?

so far, the absence of 'plans' hasn't been stated... I suspect he shopped around for the plans but I don't know the source of them

Captain Intrepid
04-14-2015, 03:34 PM
so far, the absence of 'plans' hasn't been stated... I suspect he shopped around for the plans but I don't know the source of them

If you clicked through the link on youtube you'll find that he made the plans up himself.

http://svseeker.com/anchors.htm

Peerie Maa
04-14-2015, 03:39 PM
so far, the absence of 'plans' hasn't been stated... I suspect he shopped around for the plans but I don't know the source of them

Lloyds published the proportions of "standard" anchor designs. That is where I obtained the plans and proportions of the fishermans anchor. I have also got a copy of the Bruce proportions from the same source. The other proprietary brands like Rocna et al will not be published, they are in the business of selling product, and protecting their reputation by discouraging unsafe knockoffs. That anchor looks wrong, for the reasons stated, does not look like any other anchor design I have seen at the detail level. I do not think that they have plans nor do I think that they have done any stress calculations.

Breakaway
04-14-2015, 03:58 PM
Captain Intrepid and Nick

I agree. Basing choices on proven practice, or principles, only makes sense.

Anchors are a tough nut to crack in the vein of passing sweeping judgements--and that is just what most regulations are : broad. Anchors are like antifouling paints. What works great for my boat, in my location, for my use, may not work so well for you--or may be overkill.

Interested to hear more.

Kevin

Peerie Maa
04-14-2015, 04:45 PM
Captain Intrepid and Nick

I agree. Basing choices on proven practice, or principles, only makes sense.

Anchors are a tough nut to crack in the vein of passing sweeping judgements--and that is just what most regulations are : broad. Anchors are like antifouling paints. What works great for my boat, in my location, for my use, may not work so well for you--or may be overkill.

Interested to hear more.

Kevin

It gets difficult when the non uniformity of the bottom becomes significant, which is why yacht size anchors sometimes won't work in kelp or glacial clay with cobbles mixed in. Similarly small anchors are rarely adjustable and so are always a compromise. The big anchors used on drill rigs can be adjusted to vary the angle between the fluke and shank to suit clay, mud or sand bottoms.
Anchors operate in three phases, before they are set, setting, and after they are set.

Before they are set the geometry must ensure that the fluke is presented to the bottom so that it will cut in. That is why the stock and shank of a fisherman must be equal in length and much longer than the arms. Also that is why the Bruce has that right-angle shank, it will always lay on the bottom with the cutting edge of the claw fluke presented at the right position on the bottom.

Having got the fluke in contact with the bottom, it must be presented at the right angle of attack. Too steep and it will scrape across the top, too shallow and it will not develop enough down force to bury properly. Hence the 130 degree angle on the diagram of the fishermans. The Bruce achieves this with the twist in the outer claws that screw the fluke into the bottom. They also keep the anchor stable so that it won't twist out if the boat veers on the tide.

When tha anchor is set, it is easiest to think of the fluke as a kite working upside down in a denser medium than air. The angle between the chain, projected to meet the fluke is the same as the kites line projected to meet the kites surface.

this is how this anchorhttp://www.vryhof.com/images/stevmanta_vla/foto.jpg

looks
http://lib.znate.ru/pars_docs/refs/108/107480/107480_html_m647c96e4.jpg
when fully embedded.

hokiefan
04-15-2015, 12:36 AM
what is it that you think welding sticks are made out of?


various alloys, Doctor Paul


the welding rod/wire is not the same as the parent material... simple and it's salt water in the gulf

Jeez, I can't believe I really care about this but I can't allow bad information to propagate. Mild steel is welded with a lot of different types of rods, but they all have a mild steel filler. So mild steel is welded with mild steel. No bi-metal period.

When you weld various stainless steels there are slight alloy variations, but they don't matter at all on the corrosion scale.

Peerie Maa
04-15-2015, 02:30 AM
^ Phillip is a bricky, yes? He does not stick bricks together with brick, he uses an alloy of sand and cement. Cut him some slack please. ;)

Phillip Allen
04-15-2015, 07:38 PM
somewhere there's an engineer who held cost down who isn't gonna sleep tonight

http://www.autoblog.com/2015/04/15/couple-killed-falling-concrete-slab-overpass/?icid=maing-grid7%7Ccompaq-desktopt1%7Cdl6%7Csec1_lnk2%26pLid%3D644270

Tom Wilkinson
04-15-2015, 07:43 PM
And you know it was poor engineering that caused the failure? Wasn't poor materials? Contractor skimping on the mix? Your certain he was trying to skimp on costs.

Seems like your entire argument in this thread is purely for the sake of argument.

Your entire definition of engineering is flawed.

Phillip Allen
04-15-2015, 08:00 PM
Best anchor I have seen was put into use was by one of the ex members of this forum - it was a 350 chevy engine block - he tied his boat up to it with about 30 feet of chain and his 20 footer rode out 3 hurricanes with that holding it down - the storm eye passed overhead with 2 storms so the boat got pulled from all directions. One of them was a Category 3. Never drug anchor.

you must remember that engine block was engineered

Paul Pless
04-15-2015, 08:01 PM
ex members of this forum banned for life?

Mrleft8
04-15-2015, 08:13 PM
I'd trust an anchor I built myself over any other anchor...... Except an anchor built by Jim Ledger...... If I watched him build it.

Ian McColgin
04-15-2015, 08:30 PM
I don't think much of a lump of iron that's less than 700# and a poor shape but since the thing is not something you bring aboard to go for a sail, it's a mooring, a poor mooring, and not an anchor. It's fun to feel clever repurposing an old engin block but you should plan on using twice as much weight for that sort of mooring as you would with a proper mushroom. If you can get the weight, the price might be right.

As to anchors - My prejudice runs towards properly forged anchors and I don't trust welded anchors. Further, having tested Herreshoff pattern (exact), Danforth, Bruce and CQR anchors against knock-offs, I know that the better anchors are very exactly shaped and porportioned. If not right, an anchor's not right. I can't from a video judge the quality of these guys welding and sure can't judge how well they handled the design so I'll not say it's bad. Just not for me.

Anchor design is an evolving and interesting field and there are new anchors out all the time. At least once a decade there's a new one that's worth using.

Dumah
04-15-2015, 09:00 PM
What do I think of this? Frankly, not much, and I come from a commercial side of sailing. Feel free to risk your own with this "tackle", I'll be in another body of water :d.

Dumah

hokiefan
04-15-2015, 10:51 PM
somewhere there's an engineer who held cost down who isn't gonna sleep tonight

http://www.autoblog.com/2015/04/15/couple-killed-falling-concrete-slab-overpass/?icid=maing-grid7%7Ccompaq-desktopt1%7Cdl6%7Csec1_lnk2%26pLid%3D644270


And you know it was poor engineering that caused the failure? Wasn't poor materials? Contractor skimping on the mix? Your certain he was trying to skimp on costs.

Seems like your entire argument in this thread is purely for the sake of argument.

Your entire definition of engineering is flawed.

There is nothing in the story to indicate what the root cause of the failure was. Yes, it COULD be engineering. But it could also be an original construction flaw. Or for that matter it could damage from a vehicle involved in the current construction. There is nothing approaching a proper incident investigation spelled out in the linked article. I imagine one was done to determine the root cause, I really hope so. But the author didn't discuss it.

Cheers,

Bobby

Phillip Allen
04-15-2015, 11:01 PM
There is nothing in the story to indicate what the root cause of the failure was. Yes, it COULD be engineering. But it could also be an original construction flaw. Or for that matter it could damage from a vehicle involved in the current construction. There is nothing approaching a proper incident investigation spelled out in the linked article. I imagine one was done to determine the root cause, I really hope so. But the author didn't discuss it.

Cheers,

Bobby

what a refreshing change from the usual 'pouncing' we see here in the bilge... I congratulate you

hokiefan
04-15-2015, 11:15 PM
what a refreshing change from the usual 'pouncing' we see here in the bilge... I congratulate you

I only "pounce" on you when you deserve it.

Cheers,

Bobby

Phillip Allen
04-15-2015, 11:26 PM
I only "pounce" on you when you deserve it.

Cheers,

Bobby

It just gets better and better... now you advise against judgment

hokiefan
04-15-2015, 11:30 PM
It just gets better and better... now you advise against judgment

You'll have to explain yourself better, that makes no sense at all.