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    Thread sizes

    The bore size would be O.D. - 2(0.54127/TPI) for a Unified Thread. This is Maximum Material Condition, the smallest bore size.
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    Thread sizes

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    Hardened or soft Gibs

    Why aren't gibs made from hardened steel. It would seem to me that based on the principle of lapping (where the abrasive embeds in the softer metal and laps the harder metal) that the gibs would wear and not the cast iron bed or ways. Especially on non-hardened cast iron ways using a brass gib.
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    Fix a miss aligned hole

    And glue the new plug in with locktite.
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    Tapping Thread Depth

    "This is a tie rod fitted on a helicopter cargo pod...." Well that is a whole new ballgame. This seems to be a critical thread. What happens if it fails? Aircraft certified?
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    Inside Dial Caliper , anyone use them ?

    When you have nothing else they're great. Strictly by feel. Also, I like them for shrink fitting - set them to the size of the bore (cold) then when you heat up the bore and they flop around inside the expanded bore you are good to go.
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    Formula for calulating Unified Thread Pitch Tolerance

    I think the Pitch Diameter for a UN or Metric 60 degree thread is - Nominal Diameter minus 0.64952P. (Maximum Material Condition)
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    Should I become a machinist?

    Find what sets your soul on fire and go do that - if you really enjoy your career you will never have to work a day in your life. As a Machinist every day was different and challenging. Also, now that I am retired I have a mini lathe and continue to enjoy my trade immensely. Are you looking for...
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    Newbie Machinist Seeking Advice

    Being trainable is just as important as experience. $18/hour is your chance to prove your worth/integrity. I once got hired at below the advertised wage 'cause I smashed up the machine in the interview. By the first paycheck I was up to the advertised wage. I usually went directly to the foreman...
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    Northrop Grumman lousy machining quality

    I heard that when the first cosmonauts and astronauts got together in space the astronauts commented that the Soyuz table legs were not all the same diameter but the Apollo table legs were precision machined. The cosmonauts said 'So what, they're only table legs'. :)
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    Don't get complacent about shop safety

    Thank you for posting this. A simple clothes thread almost cost you bigtime. Is there a forum for close calls like this? I am sure we all have similar stories and it would be good to pass them along.
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    Cutting precision tapers with a Taper Attatchment on a Lathe

    Here is a tip if you are getting lines on your taper. The pressure of the cut and the backlash of the taper attachment should complement each other. From- "Turret Lathe Operator's Manual" Warner and Swasey.
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    Trouble to parting off on a regular lathe

    Up the speed, use oil, tool upside down run it in reverse.
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    UNJF Thread

    I am pretty sure UNJ is always class 3. The tolerances are applied after coating i.e. Hard Balck Anodising. If only colored anodising ignore it as the normal tolerances will consume 0.0002".
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    What's the Best Tap for my Application?

    " Should I use a higher H factor? Would that mean?" H3 is a tap that is 0.0015" bigger on the pitch diameter so the tapped hole will be bigger.
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    Thread cutting question. Harbor Freight mini needs to cut 1.5 metric thread (16.9TPI)

    Google "Gear Calculator" - here is one, Change Gears for Threading - LittleMachineShop.com You will be single point threading, see Youtube for instructions.
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    Test indicator arm not moving

    I just bought a dial test indicator, then I dropped it and the needle would no longer move. I took the side plate off and discovered that if I loosened the 2 screws holding the mechanism to the body it started working. So I loctited one screw in a loose position. I did not want to return it or...
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    OT 19th c Comments on Speeds/Feeds/Tooling Taylor Taylorism

    I read in the book where he invented HSS that he continued heat treating at a higher and higher temperature and came to a point where the hardness dropped off but he continued heating anyway (until the steel melted). What he discovered was that the hardness initially dropped and then suddenly...
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    Useful. Tech college project