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Thread: Damascus Razor Edge Chisels

  1. #31
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    I don't get that statement,Malcom. If the Saber jet was already a "supersonic" aircraft,why did they continue to try developing aircraft that were supersonic,such as the Bell X1? That's how that works out for me. This process continued into the era of the Delta wing jet. They thought they had all the power they needed,and had done the math. But,the jet just would NOT break the sound barrier. A scientist invented what is now called the "Area Rule" in aircraft design. He narrowed down the body of the plane where the wings joined it. The jet would then go supersonic. He correctly reasoned that the air "saw" the bulk of the body + the wing as a large "lump"(the best word I can think of),that had to be pushed through the air. This large cross sectional "lump" was too much for the engine to over come. Narrowing the body decreased the sum total of the cross sectional area at that point. I remember reading about the new "wasp waisted" aircraft in "Science and Mechanics" back in the 60's.

    Re "real" Damascus steel: I can';t recall at all my chain of thought at the time,but a year or 2 before I read how scientists were re creating Wootz steel,I had already done much the same thing. I bought some annealed HSS steel square bars,and was hammering them only at red heat. VERY hard work. I was hammering them down into thinner square,tapering engraving chisels. The type driven with small hammers. Called "Die Sinker's Chisels" more correctly. I still use them today.

    I was over at the Gunsmith Shop letting them try out a few of my chisels. One guy was hammer engraving a groove up the tang of a file. He approached the hardened area of the file. I said to just keep going. The chisel kept on cutting when it was over 1/8" into the hardened part of the file,before the tip broke off! They were duly impressed !

    My left shoulder always hurts me 24/7 from tearing out the ligaments first in the 8th. grade boxing,then,a year later digging a ditch to bury water pipe 4' deep in Alaska with a mattock.(Even today I refuse to have a mattock ! I hate the ugly things). So,I hired one of the blacksmiths to hammer me out a bunch more engraving chisels. He complained at how hard the steel was at only red heat! Imagine those poor guys hammering a hockey puck size billet of high carbon steel into a SWORD!! My steel was M33 HSS,and it did decarb some,being heated while unprotected rom the air. I just ground away some of the outer layer when finishing the chisels. They look pretty rough and ready,but they work just fine. The tool steel dies I have posted here were chiseled out with those chisels.

    It was said that they air cooled(quenched) this sword by having 2 tall stones close together,with a tall,narrow gap between them,where by the venturi effect,air at fairly high speed would rush when the wind blew,in the right direction.
    Last edited by george wilson; 01-19-2017 at 6:15 PM.

  2. #32
    Well. I found this in an article about the F86 at Boeing.com/history:

    "Forerunner of the operational Sabre was the XF-86, first flown Oct. 1, 1947, by North American Aviation test pilot George Welch. A few months later, Welch became the first pilot to fly the plane at Mach 1 in routine flight. Although technically rated as subsonic, the Sabre was no stranger to supersonic speeds."

    That surprised me, because I thought I remembered "horizontal flight" being part of it too. So I did a bit more searching. Seems like there's a long standing argument whether Mr Welch or Captain Yeager actually broke the sound barrier first. But there were lots of references to Welch getting that Sabre prototype into supersonic flight while diving. Never knew any of this before.
    Fred
    "All that is necessary for the triumph of evil is that good men do nothing."

    “If you want to know what a man's like, take a good look at how he treats his inferiors, not his equals.”

  3. #33
    Quote Originally Posted by george wilson View Post
    I don't get that statement,Malcom. ...
    Find the pilot of an F-86 Saber (any variant). Talk to that pilot. Convince him (or Her) that his (or Her) aircraft was subsonic. Let me know the results of that discussion.

    Quote Originally Posted by george wilson View Post
    ...why did they continue to try developing aircraft that were supersonic...
    ...continued into the era of the Delta wing jet.
    ..."Area Rule" in aircraft design.
    My dad spent 20 yrs in the Air Force - primarily in B-17, B-29, F-84, F-86D, & the F-102 (area rule applied). He lived your referenced era. He'll be in my shop Sat, I'll try to convince him the Saber wasn't supersonic and let you know what he says.

    My chosen path in life was to be an Aeronautical Engineer and I can still pull the books out if you like. Pres. Carter and his peace dividend (along with my father's friends still in the service at the time) convinced me I would starve to death if I persevered. Mechanical Engineer was the fallback plan, and that led to career as Control Systems Engineer (maps of this maze are available).

    Interestingly, we are still 'continuing to try to develop aircraft' - - to something faster, better, smarter, safer, etc..

    ...We really should start another thread!
    Last edited by Malcolm McLeod; 01-19-2017 at 9:27 PM. Reason: gotta be PC!!

  4. #34
    Quote Originally Posted by Frederick Skelly View Post
    ... Seems like there's a long standing argument whether Mr Welch or Captain Yeager actually broke the sound barrier first.
    There are a few P-47 pilots who'd probably make this claim as well! Especially when a full power dive in it saved their behind. It was well known for reaching the limits of (aerodynamic) compressibility (but I'm pretty sure the adrenaline rush just added a few knots to the speedo).

    The pilots were fond of saying that another aircraft might out climb them, but they could out fall anyone! Must have been a Damascus prop..??!!

  5. #35
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    This thread keeps getting longer, and I keep checking it thinking I will learn something new about damascus steel, but the aircraft stuff is interesting too. Since you all made me read that, I had to go to wikipedia, and read up on the F-86, and according to wikipedia it is a "transonic aircraft" which I gather means it can reach the speed of sound, but not fully break through the shock wave that forms the "sound barrier."

    The Damascus steel information is very interesting. Thanks to everyone who posted on that.

  6. #36
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    Well,if you want to really keep reaching for it,even the Spitfire could just about reach the speed of sound in a power dive. But,a number of pilots wished they hadn't,because the controls got frozen,and they couldn't
    get out of it.

    I will happily agree that the F-86 was "Trans sonic". But,that is not the same thing as "Supersonic". Not by a long shot.

    The P-38 had to be fitted with special wing "slats" to keep its controls from freezing up in high speed dives.

    But,this thread is NOT ABOUT AIRCRAFT. The staff may lock it as it has reached the end of its usefulness if this offshoot keeps up.

    Yes,I well recall the Jimmy Carter days with my double size house payments during his era.
    Last edited by george wilson; 01-20-2017 at 9:48 AM.

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