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  • Wong Shafts?

    Quote from Wishihadgills

    Tinman: I like your test on the yield stress but I would have to ask about heat treating (tempered) steel. Im sure we agree that heating and cooling steel will cause it to harden ( become more brittle as well) or other affects depending how its done. How much would variation in this process from company to company? What about the heat treating of different alloys?


    Different heat treatments will change the final yield stress enormously. But not the Young's modulus. For example, with 17-4 stainless, there are several common heat treatments known as H900, H1150, etc. based on the temperature of the heat treatment. They produce metal with different yield stress, hardness, elongation (brittleness), toughness, and other properties. But the Young's modulus remains nearly constant,

  • Wong Shafts?

    Assume that I have two shafts (one stainless, and one spring steel) that are identical in every way except for the material.


    If I hang the same load on each shaft, as in my experiment, they will bend the same amount. But only up to a point.


    As the shaft is bent, the steel itself is stressed, and the further the shaft is bent, the higher the stress in the steel. As long as the stress remains below a certain point, called the "yield stress", the shaft will go back to its original shape when the load is removed. If I bend the shaft until the stress in the steel exceeds the yield stress, then the shaft will stay bent, and will not return to its original shape when the load is removed.


    Different steels have different yield stress, and spring steel has a higher yield stress than 17-4 stainless (generally). What this means is that I can put a heavier load on a spring steel shaft, and though it will continue to bend, it will still remain below the yield stress and will go back to the original shape when the load is removed.



    Quote from Wishihadgills

    So basically there is no advantage to the coated shaft other than that they are cheaper?


    The advantage to a spring steel shaft, depending of course on the type of spring steel, is that it can withstand greater stress than a stainless shaft while still remaining in the "elastic" range and returning to its original shape when the load is removed.

  • Wong Shafts?

    All common iron based alloys have about the same spring rate, called Young's Modulus, and will deform about the same amount under the same load. What is different is how far they will deform before they take a permanent set.



    Edit -


    I did a quick test, just to see if that theory would hold.


    On the left is a 9/32" stainless shaft, with a measured diameter of 0.280". On the right is a 7.5mm spring steel shaft, with a measured diameter of 0.292".


    Stiffness of shafts is proportional to diameter to the fourth power. So the spring steel shaft "should" deflect a little bit less by virtue of its larger diameter. (0.280/0.292") to the fourth power is 0.85. So the spring steel shaft "should" deflect about 85% as far.


    The stainless shaft deflected 5-1/2", and the spring steel shaft deflected 4-3/4", wich is 86%.

  • Broward Beach Conditions

    Not sure where there are grilles, cuz the only spot I knew was at Dania, and they took them away. Anyone know?


    I would say for us to go to the spot where Judah and I got our hogs, but there are no grilles there either. I would like to get some more bugs though... Love fresh bugs on the grille.

  • What is your favorite gun and why?

    What lunkerbuster said... its really about personal preferance. If you're hornet is shooting low, maybe its time for a new gun.


    Some more things you should consider is whether you like wood guns, or wanna go to a metal gun. Like LB said, you have to decide whether you like your midhandle or would prefer a euro. I like shooting with one hand, so I have a euro. If you want a metal gun, popular brands are: Rob allen, rob allen, and... rob allen lol! j/k. I really like rob allens.


    I see you're from Boca. My advise is to head up to Florida Freedivers, and talk to them up there. They are really knowledgeable, good people who will hook you up with the right gun for what you do.

  • Looters Pirates of XXI century

    Yet another perspective. If this treasure is in fact from the wreck of the Mercedes, then a lot of people seem to feel that the people of Peru have a reasonable claim. From this article http://www.coinnews.net/2008/0…pwreck-treasure-mix-4163/


    "With the possibility the treasure came from the Mercedes, a Spanish 34-gun frigate that left Peru and was close to home before it was sunk by the British fleet in 1804, ASPEC believes the coins were made with Peruvian metals and minted in Lima.


    Jaime Delgado, owner of ASPEC — the Peru consumer advocates group — commented in a statement,


    "…if it is found that these coins were minted in Peru, with gold stolen from Peru, then beyond international agreements, there is an ethical and moral issue."


    In an International Herald Tribune article today, Delgado was also quoted as saying,


    "This gold was stolen from the Incas."

  • Looters Pirates of XXI century

    It's interesting to wonder where that logic would end.


    If the government enlists a luxury liner to transport troops to a battlefield (as the U.S. did in WW I), then I guess that I could logically agree that it was a commercial vessel fulfilling a State function.


    If the same luxury liner is just carrying a bit of U.S. Mail across the Atlantic, is it still fulfilling a State function? After all, mail service is a government service . . .