25' Double Eagle aluminum build (placing stringers)

Discussion in 'Metal Boat Building' started by Northeaster, Mar 10, 2014.

  1. yofish

    yofish Previous Member

    I still don't understand the dye-pen bit. No builder I know does that. I have no idea what adhoc is about with the dye testing before 'capping' as I cannot conceive of a situation on your build where you will be doing a root pass and then capping. Perhaps somewhere on the rudder shoe? More of that 'real' builders vs. us rubes nonsense.

    I'm trying not to assume anything other than why you would waste your time with dye penetrants unless you were uncertain of weld quality. I have a 3-can set that's 30 years old; that's how often I use it. If everything is okey-dokey, why then even bring it up? If your welds are strong, as you say, then get after it!!!
  2. Ad Hoc
    Joined: Oct 2008
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    Ad Hoc Naval Architect

    Then clearly you do not weld plating greater than 5 mm thickness.

    Proboat Order of Assembly - October-November_2014.jpg

    As shown above, by typical edge prep details.

    Visual inspection of welds is no guarantee of strength or flaws in the weld. As I said before, your concept of quality is very different from mine and which we must work too. Just because you do not care about quality does not mean others must follow your approach blindly.
  3. Northeaster
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    Northeaster Senior Member

    For my part, I was not worried about the strength of the weld, nor the general weld quality - I realize it is not professional, nor perfect, but I believe it is strong.
    I had some small porosity not a great deal. Most tiny bubbles/ porosity ground out easily and took off almost no material - not enough to affect stregnth nor need rewelding / building up, capping etc.
    But in a couple of spots the bubble was larger / kept going as I went deeper, so I had to ground out enough material that it required another short pass in that area.

    The main reason I decided to dye test was to test for leaks ( i.e. potential porosity that I hadn't found) - before welding a box keel overtop of the main keel seam (making it harder to repairs leaks later).
  4. yofish

    yofish Previous Member

    "Visual inspection of welds is no guarantee of strength or flaws in the weld. As I said before, your concept of quality is very different from mine and which we must work too. Just because you do not care about quality does not mean others must follow your approach blindly."

    I have to hand it to you, you are a master of doublespeak. Can we agree that using something like Crack-Check is a VISUAL process?

    I seldom use anything above 1/4" for plating and I never would use the recommendation of that nice chart if you consider 1/4" as 6mm. If anyone is interested I would explain my procedure but won't waste the time on you.

    More to the point: anyone that needed to check his welds with dye would never be hired by me, even as a rookie.

    Your comments about quality are just stupid. And no kidding, others do not have to follow my approach blindly? I'm shocked! Seriously, do you even proof (for basic coherence) what you type?
  5. Ad Hoc
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    Ad Hoc Naval Architect

    Oh dear, jumping off the deep end again without checking if there is water!

    So, firstly, please tell me how you check a weld for strength, visually? Please , seriously tell me, I am all ears. Please explain in detail.

    Secondly, please tell me how you can see a microscopic crack or porosity visually? Again those hairline cracks you can't see with the naked eye without assistance such as dye-pen...please explain in detail, again, im all ears.

    It seems you are unaware of the term NDT, that stands for Non-Destructive-Testing. The clue is in the name.

    Dye-penetrant shows/highlights flaws that are undetectable by the naked eye. That is why it is called Non-Destructive-Testing, NDT. One is testing the weld without destroying it to locate flaws.

    Even their website, as all will, say the same too:

    "..Visible liquid dye penetrant testing is a 3 step process for detecting faults in welds, casting and alloys.."

    So again, please enlighten us how you first check the strength, obtaining the mechanical properties of a weld, visually? Secondly how can you find microscopic hairline cracks or porosity that may be present, visually?

    Good, then they can be hired by a professional company then that understands and requires NDT and that no one can spot LOP/LOF or porosity or even know the mechanical strength of a weld, visually. That is pure snake oil salesman stuff.

    Plenty, all your comments above and on other threads. You hang yourself and don't even recognise it, that's what is so sad. :(

    I know you don't like tables, because these are facts and not hearsay. So here is another for you. standards that must be complied with, which of course you clearly demonstrate you don't:

    BN EN 288-4.jpg

    Oh, and for the other table:

    Here is one of endless sources all saying the same thing, in other words the 100% opposite to you:

    Plate prep details other sources.jpg
  6. Ad Hoc
    Joined: Oct 2008
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    Ad Hoc Naval Architect

    Since you're the visual master (no need for any NDT), can you tell me what is wrong with this weld please:

    A1-DH visual.jpg

    And its strength please too :)
  7. yofish

    yofish Previous Member

    Were you born without basic comprehension skills or have you developed it on your own? I'll do this S-L-O-W-L-Y so you may be able to grasp a simple sentence:

    "I seldom use anything above 1/4" for plating and I never would use the recommendation of that nice chart if you consider 1/4" as 6mm."

    Now, look at those charts that you love so much. Do you not see that there is more than one way to skin your cat? Is it possible to stretch your limited experience that only includes cut and paste charts and so obviously little real-world experience to imagine that I HAVE MY OWN WAY of addressing the matter? I - DON't - DO - IT - THAT - WAY.

    And really, showing a chart of the recommended testing as if someone was getting a coupon is just silly.

    As far as the other picture that you fling against the wall like feces from a zoo gorilla; I haven't a clue as to what's wrong with it but will comment that I hope that it's not an example of your shops' work because it looks like crap. Is it some trick or special exercise you teach your welders to make excessively wide welds vs. base thickness? I don't know. To me, it is just another of your stupid antics.

    I'll make you an easy deal: just show me that dandy 'simple' chine detail that you so offhandedly offered to that poor fellow using the specified materials and I promise that I'll never get in the way of you giving bad advice again. How about it? For the record, just a picture of a 5.8m skiff made of .125" and .100" and your suggested 'simple' treatment showing said assembly. Should be simple to do, no? I go away for ever. Put up or shut up.
  8. Boat Design Net Moderator
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    Boat Design Net Moderator Moderator

    Probably a good point to place a request in this thread: obviously everyone has frustrating days, but if everyone could please make an effort to try and be polite to others, it makes the discussion better and more pleasant for everyone. It would be better to direct personal jabs at others to some other forum or facebook please, and let's try and keep the discussions on the technical aspects, boatbuilding methods, and build at hand if possible. Thank you all very much for helping to keep this a positive and enjoyable place to learn and share knowledge.
  9. Ad Hoc
    Joined: Oct 2008
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    Ad Hoc Naval Architect

    I am trying but it appears some posters don’t understand the difference between facts and subjective comments. And that there is always more than one point of view and accepting it rather than being pugnacious and polemic in their replies because it differs from their own.

    The real issue is that the world in which I work is all Classification and high quality and demonstrating that the quality is there and can be maintained, no matter what. No subjective thoughts or feelings, it must be demonstrated independently. Yet for others they do not work in such an environment and also do not see the need or even recognise the need for such QA, as their environment is worlds apart from mine. They appear unable to look beyond what they do and unwilling to accept there are other ways of construction especially with heaver plate thicknesses.

    However, referring directly to Yofish’s comments:

    So you say you don’t’ use 6mm, fine, not a problem with that….but yet you feel qualified to say that the tables/charts are not correct. Hmm…how odd. So no experience in welding such thicknesses, but you feel you can say whether it is correct or not. Most interesting behaviour.

    Oh I do, and many others do too. But as you have repeatedly demonstrated on this thread and others, there appears only one way…your way. Only you are saying this, no one else. All I present are facts for the OP to make up their own mind which way to proceed; all images above ref’s can be provided. Since any other way other than what YOU do, is not acceptable or simply a waste of time or nonsense as noted many times above. So you see that there is more than one way from a chart/table…but do not see that with your own methods. Again, most interesting behaviour.

    As yet again noted here:

    If I showed you a detail that satisfies you and only you, suddenly it is all sunshine and light. Ergo, you don’t get it. It is not about me and it is most certainly not about YOU, it is about the question at hand.

    So you haven’t replied saying that you can see the strength of the weld as you appear to maintain…is that correct?

    So not a clue, yet you feel qualified to tell others what is good or bad practice? Also you’re making an assumption of what that weld or test piece is too. Asking what it is would be the most logical question, especially in the absence of you being able to tell what is wrong with it (if anything), but another polemic is easier, which does not help the OP at all.

    Having an open and enquiring mind appears to be harder for some than others.
  10. Mr Efficiency
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    Mr Efficiency Senior Member

    ........" déjà vu all over again " :D
  11. yofish

    yofish Previous Member

    North, the fact is that the dye test is not going to tell you that there is a 'leak' unless it is a through and through crack which is distinct in its presentation. one can have lots of porosity and no leaks. Kevin Morin said one of the most right-on things about weld quality somewhere where I can't remember and that was, to paraphrase, that there are jillions of aluminum boats out there and him, like me, despite having seen the guts of many of them with rather sketchy welding, there has been no rash of dead bodies from them falling apart. This is not in any way a recommendation of an approach to boat building, of course, but it is an incontrovertible fact.

    However, now you come to a place where you're really going to have to pay attention to leaks (or not). No matter how you cut it, there is the fact that you aren't nano enough to fit inside the keel box to weld both sides everywhere. Therefore, if you want it dry you'll need to sharpen things.

  12. yofish

    yofish Previous Member

    You realize that you didn't really respond effectively to any point and especially to my direct challenge? All that word-salad of misdirection when all you have to do is post one pic and I STFU? All that high-flown hyperbole doesn't work on us proles. You're boxed and you know it.

    <removed: would like to keep thread away from personal jabs and encouraging further fighting and keep it on the factual issues being debated in the thread rather than have the thread ruined as a personal fight which isn't really of much value to anyone.>
    Last edited by a moderator: Apr 30, 2015
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