Open Source Anchor Project

[JonJo]

I have no doubt your motives are as pure as the driven snow. And the outcome will be interesting.

I think you said, much more effectively and eleoquently, what I have occasionally said - 'anchors are a compromise'. There is no perfect answer - I'd like to think there might be. Hopefully you will move us toward that perfect answer.

You sadly allowed a sentence to intervene that looked derogatory. I obviously misinterpreted, for which I apologise.

Jonathan

[JonJo]

On your sideways load, simply bolt the fluke, flat to a concrete floor - and load the shank. If you simply want to test the shank, make it a bit longer, at the crown, and bolt it to a steel beam. Then load the shank. All you will need is a load cell and a block and tackle.

The part I cannot work out how to do:

Most loads are snatch loads, how do you impart a snatch load, that simulates the sort of snatch load on a yacht or anchor, at 90 degrees (to the anchor or shank above)?

Jonathan

[estarzinger]

[QUOTE=JonJo;1425511
Most loads are snatch loads, how do you impart a snatch load, that simulates the sort of snatch load on a yacht or anchor, at 90 degrees (to the anchor or shank above)?

Jonathan[/QUOTE]

That's easy . . . I have it worked out for some rope testing (tethers and jacklines) . . . drop an engine block a meter or two!

[congo]

Quote:
Originally Posted by Delancey
I'll make it you, can break it. Deal?


Estarzinger Wrote:

I have the capability to pull 10 tons, but my preference comfort level is to be max 5 tons (and my load cell is more accurate there) . . . stuff snapping at 10 tons is scary . . . You probably want to know 'yield points' rather than 'actual breaking point' and yield is safer for me.

I will have to dream up some clamping methods. Should not be too difficult but any ideas welcome.
__________________


Rex Wrote:

If your load cell is not accurate from point A to point B then it will junk your test, further it would be obvious if this is the case (more accurate there) your load cell is faulty, have it fixed and regularly recalibrated. Your expertise in this field comes across as being professional. I am at a loss as to why you would test with a faulty load cell.

Estarzinger Wrote:
That photo is a bit funny . . All the broken junk off to the right edge of the pic, and I have to believe it is not (and is rather some high strength synthetic) but it looks like a leather strap taking the load over the fluke, and the shackle thru the shank looks wrong. The whole picture just has a junk yard feel to it.


Rex Wrote :

They do not do running commentary on photo’s, for your benefit, the shackle, as you call it is a hammer lock, very high strength and required as this test was to destruction, leather strap it is not, it is of Kevlar, If you had of left this wording off ,( junk yard feel to it.)

Then there would have been no distraction from Delanceys thread, I see no good reason as to why you threw that in, others responded obviously as they thought there was more to it, then, made to look the villain?



[COLOR=black][QUOTE=JonJo;1425511[/COLOR]
Most loads are snatch loads, how do you impart a snatch load, that simulates the sort of snatch load on a yacht or anchor, at 90 degrees (to the anchor or shank above)?

Estarzinger Wrote:
That's easy . . . I have it worked out for some rope testing (tethers and jacklines) . . . drop an engine block a meter or two!

Rex Wrote:

Dropping an engine block? I applaud your effort to try and simulate side loading but again I am equally amazed that you haven’t thought this threw to well, when dropping an engine block it is a solid impact, can you explain to me how this simulates the dragging lifting of the chain until snatch is achieved, can you also simulate the sideways floating movement from any vessel that is apparent when a snatch load is taking place?

These questions are only the tip of the iceberg in reality with what you will have to try and calculate, anyway good to see someone having a go.

Regards Rex.

[estarzinger]

Originally Posted by congo

If your load cell is not accurate from point A to point B then it will junk your test, further it would be obvious if this is the case (more accurate there) your load cell is faulty, have it fixed and regularly recalibrated. Your expertise in this field comes across as being professional. I am at a loss as to why you would test with a faulty load cell.

Rex, you are making some bad assumptions. My load cell is in fact a quite accurate 5ton model. I can make 10ton measurements with it by using a 2:1 purchase, but that adds some friction and a little inaccuracy. That is not a faulty load cell, just that when I bought it I though 5tons would be plenty, and I was suggesting that we try to keep the anchor tests to that limit

junkyard . . . I see no good reason as to why you threw that in, ?

I made that comment because a relatively large experience base suggests that in manufacturing and testing that you generally get better quality and more repeatable results in an organized environment. I thought it odd that a "class test" would be carried out in such a "junkyard" . . . I still think it odd.

Dropping an engine block? I applaud your effort to try and simulate side loading but again I am equally amazed that you haven’t thought this threw to well, when dropping an engine block it is a solid impact, can you explain to me how this simulates the dragging lifting of the chain until snatch is achieved, can you also simulate the sideways floating movement from any vessel that is apparent when a snatch load is taking place?

Rex, you are again making bad assumptions . . . You seem to think I would do the drop with chain. I can in fact vary the line to any elasticity I want to get any level of snatch, including progressive inelasticity if that's what is necessary. I don't know the answer yet to how sharp the snatch should be, but I will after I measure it on a couple boats, and then I can replicated it. I will have 10hz load curves and will aim to duplicate them. With more money I would do it with computer controlled rapid hydraulics, but the engine block and variable elasticity line will have to suffice unless you want to fund it Just FYI, you may not be familiar with it, but the "drop test" is quite accepted by various standard bodies for simulating snatch loads. It is an inexpensive way to bring a load on more quickly than inexpensive hydraulics (which are slowish)..

..........

[congo]

Estarzinger wrote:
Rex, you are again making bad assumptions . . . You seem to think I would do the drop with chain. I can in fact vary the line to any elasticity I want to get any level of snatch, including progressive inelasticity if that's what is necessary. I don't know the answer yet to how sharp the snatch should be, but I will after I measure it on a couple boats, and then I can replicated it. I will have 10hz load curves and will aim to duplicate them. With more money I would do it with computer controlled rapid hydraulics, but the engine block and variable elasticity line will have to suffice unless you want to fund itJust FYI, you may not be familiar with it, but the "drop test" is quite accepted by various standard bodies for simulating snatch loads.
Rex Wrote:

Quote from Evan, you seem to think I would do the drop with chain.
Rex Wrote:
I didn’t say or indicate that, this is your assumption.
Oh well I suppose if I don’t ask the question, then obviously I am supposed to guess, what you haven’t explained, therefore in your eyes I am making bad assumptions? Why not just assumptions.
Evan Like you with me, I am losing faith in the knowledge you present and find myself either asking the question or making bad assumptions, so it goes both ways.


[QUOTE=JonJo;1425511
Most loads are snatch loads, how do you impart a snatch load, that simulates the sort of snatch load on a yacht or anchor, at 90 degrees (to the anchor or shank above)?

estarzinger Wrote:

[B]That's easy[/B] . . . I have it worked out for some rope testing (tethers and jacklines) . . . drop an engine block a meter or two!


Rex Wrote:

Well my friend Evan, if it was that easy why haven’t you done this before, as matter of fact why don’t the classification authorities have a side loading method along the lines that you have described, Evan I would give up my day job if I were you and offer your assistance to the Marine authorities. The drop test is , has, in a way been applied , accepted by any classification for dropping an anchor onto a concrete block, testing for sea bed impact strength.

I will be waiting with baited breath and so will my engineers when you present your method.

Did you know that a proof load test also takes into account sideways stresses to a point, a point where as how many bent shanks do you see on anchors that are certified, well you will not believe me so you this time will have to make an assumption, I hope it’s not bad like mine.
Estarzinger Wrote:

I have the capability to pull 10 tons, but my preference comfort level is to be max 5 tons (and my load cell is more accurate there) . . . stuff snapping at 10 tons is scary . . . You probably want to know 'yield points' rather than 'actual breaking point' and yield is safer for me.

I will have to dream up some clamping methods. Should not be too difficult but any ideas welcome.
Rex Wrote:
This just an example, surely I could be forgiven into thinking first, your load cell is capable of reeding ten ton , then secondly (and my load cell is more accurate there surely it’s a fair assumption that your load cell is faulty by the way you have written it, load cells are accurate at either end of the scale. Frictions and in accuracies from attachments being applied are measured and tuned out of the load cell before commencing.
__________________
Regards Rex.

[estarzinger]

Thanks for all the kind and informative support Rex. Are you related to craig smith?

[congo]

Thanks for all the kind and informative support Rex. Are you related to craig smith? __________________
www.bethandevans.com

Your more than welcome, come on Evans don’t take it all so seriously, people in glass houses shouldn’t throw stones.

You know you do have me a bit worried, I will have to check my heritage you just never know, but I call your comment a bad assumption.

Regards Rex.

[congo]

Delancey,I sincerely apologize for the interruption on your thread, from here on in just don’t mention Anchor Right, use photos, or ask questions in relation to Anchor Right and their products, this is the only way you can stay on topic, if someone regardless of whom makes unsubstantiated or uncalled for comment then I have the right to reply.
By the way, you guys are doing a great job.
Regards Rex.

[leftbrainstuff]

Originally Posted by estarzinger

JonJo, take your AnchorRight defensiveness someplace elsewhere.

Delancey did NOT criticize AnchorRight. he simply told me it thought it was an AnchorRight product in the photo. Which seems to be correct. So your comment about "ignorance, or something worse" can just be pointed right back at YOU.

And I did NOT criticize AnchorRight (in the comment Delancey was responding to). I simply said the facility in the photo looked like a junkyard. I had, and have no idea if it is an AnchorRight facility or not - but it does look like a junk yard in the photo. That's a simple fact, not criticism.

And in the other thread . . . I simply said that I was puzzled by Rex's seeming to be unfamiliar with the equipment number formula - when I posted it he said very plainly that it was not how he thought the survey officers did it. That was not criticism. That was puzzlement, particularly given he had also said his own anchor sizing was based on the survey requirements. He must have taken the survey requirements into his own chart in a different way, and I would have been interested to learned how/what that was. There was no criticism in any of that. Simply a discussion and attempt to learn.

And what is with your dig about Mantus below. Why should Delancey want to 'ensure Mantus meets them"? He is doing an open source project. Mantus offered to help with some calculations, but Delancey certainly did not sell his open source soul to them. He is still producing a product which will compete with theirs, and I given them great credit for offering to help in that circomstance. And if/when I actually do the pulling I don't care what Delancey or Mantus or you think . . .I will just report the results. You again are suggesting bad or hidden motivation where none exists.

You are way way too quick to both feel someone has somehow slighted AnchorRight and also to attribute ignorance or bad motivations.

Is that because YOU have some hidden/bad motivation for so actively protecting/defending Rex in all these threads

(don't respond to that . . .that was just to let you see how it feels to be accused in that unfair way . . . . . I in fact only have great respect for your various attempts to bring some data to anchor testing . . . but you are way over the line in your 'attack dog' mode on these threads. . . . ).

Nicely put. I am a great supporter and user of all things open source.

[Delancey]

Rex,

I've said elsewhere and I'll say it again, many talk the talk but few walk the walk. You have for many years, through sweat and determination, produced a product which has been proven through performance. To me this is bigger and louder than any words.

As a New Yorker the last thing I would ever do is begrudge someone for sticking up for themselves so don't please feel like you have to apologize to me.

A while back I ran across a great image of destructive testing of an original Bruce Claw which I now regret not saving.

When proof testing came up I searched but couldn't find that Bruce image, so resorted to using one from Practical Sailor thinking this would be about as neutral as I could get. Obvious fail, so will try to do better next time.

I would argue with you on one point however, it's not my thread. This thread belongs to everyone who cares to participate. This thread belongs to us. I only hope we can all forgive and forget, and move forward to a productive end. If we can't do that, then maybe be should consider taking up golf instead and I hate golf so let's make this work. Much more stimulating IMO!

Best Regards

[congo]

Delancey Wrote:

When proof testing came up I searched but couldn't find that Bruce image, so resorted to using one from Practical Sailor thinking this would be about as neutral as I could get. Obvious fail, so will try to do better next time.

Rex Wrote:

Thanks for coming back, I know you didn’t intentionally put up our anchor, it was Evans comment that got my back up simply because it is a N.A.T.A. testing facility, these places are not squeaky clean like a special test labourites, Robertson’s cover an extremely wide range of testing, big oily chains greasy cables and are extremely busy, depending of what time of the day you are booked in will govern the appearance of those test facilities.

I admit it was getting a bit grotty, that facility has now closed and they have moved into a brand new facility in Melbourne, it wasn’t just the Junk yard comment but how the anchor was being tested comment, this comment also tested me as I believe Evan new it was our product and out of respect I would have though he may well have kept his thoughts to himself.

Any way that said if you want a simple side load test to satisfy your build strength just go buy a Manson Supreme of equivalent size, bolt down, drill holes if necessary and pull with load cell intact, record the load at yield, bolt your own in the same way and repeat, once you have achieved this load you’re done, if you want to go stronger you then have a bench mark from which to work to from, quote this anchor shank is as strong or much stronger than a certified S/H/H/Power anchor, that’s basically it.

All of our anchors have varying profiles they do not just size up like say Mantus or Supreme, they all vary to build strength where it is need to prevent yield before reaching the proof load required, this altering profile allows us to stick with similar shank thickness for larger model anchors, Super Sarca only.

Our anchors over 55 K.G. are all proof loaded until yield is present, for instance our 136 K.G. Excel has a proof load of ten ton, it was taken to twenty ton, before deformation.

What is interesting is by meeting the proof load test will build you a very strong side load test, H/H/Power proof load is lower, side strength obviously lower, S/H/H/Power have much higher proof loads resulting in stronger side load test.

There is a lot more to this as you do not proof load the smaller anchors to the specs provided; you use the same formula as the anchors being tested over 55 K.G. I have to go but some time whilst on the water I will try and give you some more info on this.

Regards Rex.

[vientoman]

I too would like to build and test an anchor given the cut files. I believe a .dxf file is sufficient.

can you post a link to a shared file somewhere? I have a local shop that has a fantastic water jet machine and ample welding ability.

Thanks,

[noelex 77]

Originally Posted by congo

What is interesting is by meeting the proof load test will build you a very strong side load test

Unfortunatly the proof load test is only in a vertical direction. Side loading is ignored by the standard. A deep relatively thin shank will do well in this test, but will be less strong in a horizontal direction than a thicker less deep shank.

Thus, a shank that is not very deep (like a CQR) shank will do less well in the vertical proof load test, but may be less vulnerable to bending in practice than a a shank that measures better on the sort of test used to certify SHHP anchors.

If testing the open source anchor to destruction it would also be worth getting some measurements of fluke tip strength. The non weighted ( and therefore non reinforced tip ) of the proposed design can prove to be a little vulnerable in this area although it is difficult to know adequate values without comparison measurements.

When measuring strength it important to consider that a heavier shank and / or a less sharp leading edge to the fluke will decrease performance and for a home made anchor it may be worth erring on the side of performance.

It is great that we have CF members with the knowledge, equipment and motivation to do these sort of measurements. They should be given our support.

[Jimbo485]

Bla bla bla

This is starting to get boring.

Delancey, if you want me to build a 30 kg anchor and test it in real conditions, I need the files. If you want to see the momentum lost, just carry on as you are.

Sorry about the abruptness. I am engineer myself but too much talk does not help at this point.