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  1. Replies
    29
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    1,150

    . oversize tap normally only used on heat...

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    oversize tap normally only used on heat treated parts where hole gets smaller and or out of round after heat treatment and H number varies based on size of tap
    .
    many paint tap shank green that...
  2. Replies
    22
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    1,450

    . as a apprentice 40 years ago i saw grinding...

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    as a apprentice 40 years ago i saw grinding wheels being bored out bigger ID hole on a lathe with a old end mill as a boring bar at relatively slow rpm. obviously it will dull end mill but it...
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    18
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    846

    many a finishing mill needs to cut 3 or 4 feet...

    many a finishing mill needs to cut 3 or 4 feet before its stable. that is it needs to wear in a bit. have seen over .0005" height differences in finished surfaces before.
    .
    as tool dulls and part...
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    18
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    846

    is their a chapter on sudden tool failures,...

    is their a chapter on sudden tool failures, hitting slag hard spots, false cutting edge buildup, tool vibration harmonics ?? part vibration harmonics ?? and obviously vibration can change where tool...
  5. Replies
    19
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    1,242

    a winch or chainfall is safer way to go. heavy...

    a winch or chainfall is safer way to go. heavy item rolling up or down ramp easy to loose control fast. its human nature to try to stop but heavy items can often be too much to stop and it can happen...
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    23
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    923

    not only a badly sharpened drill but a drill bit...

    not only a badly sharpened drill but a drill bit that hit a hard spot of slag can get damaged and drill oversized holes.
    .
    i have even seen carbide drill damaged drill holes .040" oversize before....
  7. Replies
    9
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    633

    sometimes due to temp change when part unclamped...

    sometimes due to temp change when part unclamped you hear a thump..... part when free it can expand or contract. when clamped if section gets longer between supports it ends to curl as excess length...
  8. Replies
    23
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    923

    . i believe thats for 75% thread and yes its...

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    i believe thats for 75% thread and yes its commonly done. just look at tap drill chart, usually tap drill size is close to that rule of thumb. drill bits can easily drill oversize especially if...
  9. Replies
    9
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    633

    many a part each time material removed when...

    many a part each time material removed when rechucked part goes bong or distorts when free of clamp force. thus why rechucking at lighter pressure and removing less material often done many times....
  10. Replies
    9
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    633

    doesnt matter if clamp is magnetic or applies...

    doesnt matter if clamp is magnetic or applies mechanical clamping force. you usually want to check for "soft foot" you usually put indicator on part, apply clamping force, see if part is distorting...
  11. Replies
    19
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    1,242

    it can be dangerous going up or down incline....

    it can be dangerous going up or down incline. runaway or going back down incline especially long one can be very dangerous. getting moving requires more push, if going up and you stop its going to be...
  12. Replies
    21
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    1,513

    . worn turcite can be like a car with both front...

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    worn turcite can be like a car with both front tires low on air. the road might be level but car with low tires appears to be leaning when sitting in the car but the car travels on a level road
  13. Replies
    38
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    1,575

    if 3" dia 4insert facemill 503 rpm at F10. .005...

    if 3" dia 4insert facemill
    503 rpm at F10.
    .005 ipt
    395 sfpm
    DOC .060"
    WOC 2.5"
    304SS at 0.2cubic inch per hp per min, machinability rating thats
    7.5hp required at 630lbs cutting force
    0.4...
  14. Replies
    38
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    1,575

    304SS if work hardened from cold rolling and not...

    304SS if work hardened from cold rolling and not annealed and full of slag hard spots can be 10x harder to machine.
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    machinability rating about 0.2 to 0.4 cubic inched per hp per minute, slag hard...
  15. picture needs to be correct file type and size,...

    picture needs to be correct file type and size, most problems are its too big a file size or wrong file type
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    windows snipping tool or screen shot often will create a smaller copy of a big image...
  16. . 1st test picture jpg at 94kb 2nd test picture...

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    1st test picture jpg at 94kb
    2nd test picture jpg 72kb
  17. Replies
    13
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    1,134

    for example 1/2" end mill, if stickout of collet...

    for example 1/2" end mill, if stickout of collet
    1.0" compared to
    2.0" stickout thats (2x2x2) or 1/8 as rigid
    .
    if titanium alloy with 0.2 cubic inch per hp per minute machinability rating
    1/2"...
  18. Replies
    6
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    755

    . there is pressure and flow rate. high pressure...

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    there is pressure and flow rate. high pressure often helps keep small holes on tooling from getting plugged full of chips. flow rate helps blast chips out of the way (like out of holes being...
  19. Replies
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    3,138

    old machines often have cadmium plated parts too,...

    old machines often have cadmium plated parts too, vanadium in steel as well as other metals can be toxic. had health and safety once collect all lead in shop. lead hammers, plumbers solder, etc
    ....
  20. Replies
    13
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    1,134

    hp limits and cutter, machine, part deflection...

    hp limits and cutter, machine, part deflection are often the limits.
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    2x longer end mill stickout length out of tool holder and deflection is 2x2x2 or 8x more
    3x longer stickout deflection is...
  21. brush plating, nickel . its like a electric...

    brush plating, nickel
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    its like a electric magic marker, dip cloth covered electrode connected to power supply in chemicals and rub on surface. takes alot of time to plate on .001" but relatively...
  22. between tram error and table being flexible and...

    between tram error and table being flexible and as slide locks tighten it moves all over the place I would say removing just .001" is being over optimistic
    .
    I usually take a precision ground block...
  23. Replies
    6
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    1,155

    I used a big ultrasonic cleaner using caustic...

    I used a big ultrasonic cleaner using caustic sodium hydroxide at usually 160F. caustic if get on skin will feel slippery cause it is dissolving your skin. it will dissolve your eyeballs too.
    ....
  24. Replies
    23
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    1,582

    . some leave material above top of finished hole...

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    some leave material above top of finished hole and ream before, then machine material off, so tapered hole part is machined off. tapered hole part usually top 0.1" of depth, depends on material...
  25. . law of the universe, stickout endmill 2x more...

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    law of the universe, stickout endmill 2x more and deflection increases 2x2x2 or 8x more deflection
    3x more stickout its 3x3x3 or 27x more deflection
    .
    it you reduce stickout 0.7 its previous...
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