• Speaking of Broaching - Are Your Bearings Really That Bad

    From Bob La Londe@none@none.com99 to rec.crafts.metalworking on Fri Apr 17 12:08:39 2026
    From Newsgroup: rec.crafts.metalworking

    More than once I've read or heard people say their bearings weren't good enough for broaching on their milling machine. Wait a minute? Do you
    drill with your milling machine?

    Okay, lets take a step back. Sure pushing a stepped cutter through a
    round hole to make a square or a hex takes a fair amount of force. I typically do that on an arbor press if I can. Its maybe not as much as
    people think though. Each tooth only takes off a little bit of metal.
    It might be an insane amount of force in a fairly thick piece of steel,
    but in most things we might be broaching is it really that much.

    Still, I probably wouldn't do that sort of broaching on a milling
    machine. If for no other reason than you can't (or shouldn't) push the
    broach through the table below the part. Yes, there are work around
    methods depending on your ability to fixture the job, the available
    clearance, etc, but that sort of broaching is best done on some sort of
    a press.

    Now here is where the cognitive dissonance comes in. A lot of broaching
    can be (is) done with a single tooth/flute tool, and engagement is
    easily adjusted to a suitable amount of force within the limits of the material being broached. Internal keyways are often done this way ona
    lathe. Lock the spindle and use the tool post to push through a cutter.
    Its not a high impact application unless the operator choose to make
    it one. A sharp tool cuts even alloy fairly well if you get the right
    amount of engagement. Sure a lathe headstock/spindle is typically more
    robust than a mill spindle, but its still axial force on the bearings.

    So why not the mill? Old? Not as robust? Shock load? Maybe to all of
    those things, but for a single point/flute tool engagement is a choice.
    Its axial load which unless its total crap is the direction in which the bearings are strongest. How much axial load are you putting on those
    bearings when you are forcing a drill through a piece of steel? You
    know you have to push hard enough so it removes a chip, because way to
    many alloys will harden up on you and stop cutting if you don't.

    In any case you have to do what you think is best, but maybe what is
    best is a little more nuanced than you think. Maybe think of broaching
    on the mill like using a clapped out old shaper. You are the one who
    chooses how hard the cut is.
    --
    Bob La Londe
    CNC Molds N Stuff

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  • From Jim Wilkins@muratlanne@gmail.com to rec.crafts.metalworking on Fri Apr 17 16:20:30 2026
    From Newsgroup: rec.crafts.metalworking

    "Bob La Londe" wrote in message news:10ru0fn$1fkms$1@dont-email.me...

    More than once I've read or heard people say their bearings weren't good
    enough for broaching on their milling machine. Wait a minute? Do you
    drill with your milling machine?

    ----------------
    A voice of experience wrote that the -two speed quill feed gears- on a Clausing mill aren't strong enough for broaching, especially with a pipe extension on the handle.

    Another sought and found replacements: https://www.wentztech.com/metalworking/equipment/clausing-8520-mill/
    "The gears in the quill can easily be broken."

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  • From Bob La Londe@none@none.com99 to rec.crafts.metalworking on Fri Apr 17 15:59:34 2026
    From Newsgroup: rec.crafts.metalworking

    On 4/17/2026 1:20 PM, Jim Wilkins wrote:

    A voice of experience wrote that the -two speed quill feed gears- on a Clausing mill aren't strong enough for broaching, especially with a pipe extension on the handle.

    If it needs a pipe extension that was a choice of engagement. Broaching
    a square corner on a mill is done by nibbling. Not firing a full size
    net shape projectile at Mach 5.

    Maybe the gears are that fragile, but if they are how do you drill with
    it?
    --
    Bob La Londe
    CNC Molds N Stuff
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  • From Jim Wilkins@muratlanne@gmail.com to rec.crafts.metalworking on Sat Apr 18 07:42:34 2026
    From Newsgroup: rec.crafts.metalworking

    "Bob La Londe" wrote in message news:10rue0n$1g4o1$1@dont-email.me...

    On 4/17/2026 1:20 PM, Jim Wilkins wrote:

    A voice of experience wrote that the -two speed quill feed gears- on a Clausing mill aren't strong enough for broaching, especially with a pipe extension on the handle.

    If it needs a pipe extension that was a choice of engagement. Broaching
    a square corner on a mill is done by nibbling. Not firing a full size
    net shape projectile at Mach 5.

    Maybe the gears are that fragile, but if they are how do you drill with
    it?
    --
    Bob La Londe
    CNC Molds N Stuff

    ----------------------
    I base how hard I push it on a deflection test with an indicator.

    I start with a center drill, then 1/8", then increase in steps it can
    handle, perhaps 1/4->1/2->3/4->1" or hole saws up to 2" or slitting saws to
    4" in mild steel. It makes chattering and other noises if pushed too hard.
    At ~700 Lbs it's not a very rigid milling machine, less so than an RF-30,
    and I don't risk breaking unavailable parts.

    I like the ergonomics of my Clausing better than a Bridgeport's for making
    one small precision part but it's definitely not for rapid volume
    production, the same as my lathe.

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  • From Bob La Londe@none@none.com99 to rec.crafts.metalworking on Sat Apr 18 11:57:10 2026
    From Newsgroup: rec.crafts.metalworking

    On 4/18/2026 4:42 AM, Jim Wilkins wrote:
    "Bob La Londe"-a wrote in message news:10rue0n$1g4o1$1@dont-email.me...

    On 4/17/2026 1:20 PM, Jim Wilkins wrote:

    A voice of experience wrote that the -two speed quill feed gears- on a
    Clausing mill aren't strong enough for broaching, especially with a
    pipe extension on the handle.

    If it needs a pipe extension that was a choice of engagement.-a Broaching
    a square corner on a mill is done by nibbling. Not firing a full size
    net shape projectile at Mach 5.

    Maybe the gears are that fragile, but if they are how do you drill with
    it?
    --
    Bob La Londe
    CNC Molds N Stuff

    ----------------------
    I base how hard I push it on a deflection test with an indicator.

    I start with a center drill, then 1/8", then increase in steps it can handle, perhaps 1/4->1/2->3/4->1" or hole saws up to 2" or slitting saws
    to 4" in mild steel. It makes chattering and other noises if pushed too hard. At ~700 Lbs it's not a very rigid milling machine, less so than an RF-30, and I don't risk breaking unavailable parts.

    I like the ergonomics of my Clausing better than a Bridgeport's for
    making one small precision part but it's definitely not for rapid volume production, the same as my lathe.

    Just checking. I know a lot of people step up through the drill sizes
    on a drill press or mill, but its usually because of a mix of low
    relative horsepower, slippage, low rigidity, and bit grip.

    In even modest production you only need a pilot slightly bigger than the
    web if your drills are in good condition and you have the horsepower.
    Split points blur that line.

    This true 5 HP (5HP 3 phase motor with 7.5kw VFD) South Bend knee mill
    has definitely spoiled me. I've pushed 5/8 (and larger) drills though
    4140HT with no pilot. In fact sometimes I will drill holes in a piece
    on the manual mill to allow for chip and coolant drainage on the CNC
    mill. I bought a set of the next size (1 to 2 inch plus) S&D drills just
    for use on this machine a while back. If you have the power there is
    nothing that removes material faster than drilling. Some will argue a bandsaw, but only if you are cutting away pieces that you could actually
    use for something else.

    I have had baby and small desktop/benchtop machines, but I've sold most
    of them. I still have the Taig (definitely can't broach), but the
    noname mill drill and RF30 have long since been sold. I am familiar
    with babying them due to low rigidity and low power. I do have a new
    mini mill I bought to do a video series on practical tackle molds you
    could make with a POS Mini Mill, but I've never had the time. Its still
    in the crate. Its a WEN. Basically a slightly better QC maybe a larger
    table version of the Harbor Freight mini mill. I would have bought the
    HF because I wanted to do the series with the cheapest mill in its
    class, but it was only available online. After freight costs the WEN
    was a few dollars cheaper. If I was buying one for real world use
    though I would go with the fixed column version from Little Machine Shop.

    I get using small machines.

    I wonder though. Can you lock the quill and broach with the knee?

    On a mini mill could you lock the quill and broach with the head?
    --
    Bob La Londe
    CNC Molds N Stuff
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  • From Bob La Londe@none@none.com99 to rec.crafts.metalworking on Sat Apr 18 11:58:04 2026
    From Newsgroup: rec.crafts.metalworking

    On 4/18/2026 11:57 AM, Bob La Londe wrote:
    On 4/18/2026 4:42 AM, Jim Wilkins wrote:
    "Bob La Londe"-a wrote in message news:10rue0n$1g4o1$1@dont-email.me...

    On 4/17/2026 1:20 PM, Jim Wilkins wrote:

    A voice of experience wrote that the -two speed quill feed gears- on
    a Clausing mill aren't strong enough for broaching, especially with a
    pipe extension on the handle.

    If it needs a pipe extension that was a choice of engagement.-a Broaching
    a square corner on a mill is done by nibbling. Not firing a full size
    net shape projectile at Mach 5.

    Maybe the gears are that fragile, but if they are how do you drill with
    it?
    --
    Bob La Londe
    CNC Molds N Stuff

    ----------------------
    I base how hard I push it on a deflection test with an indicator.

    I start with a center drill, then 1/8", then increase in steps it can
    handle, perhaps 1/4->1/2->3/4->1" or hole saws up to 2" or slitting
    saws to 4" in mild steel. It makes chattering and other noises if
    pushed too hard. At ~700 Lbs it's not a very rigid milling machine,
    less so than an RF-30, and I don't risk breaking unavailable parts.

    I like the ergonomics of my Clausing better than a Bridgeport's for
    making one small precision part but it's definitely not for rapid
    volume production, the same as my lathe.

    Just checking.-a I know a lot of people step up through the drill sizes
    on a drill press or mill, but its usually because of a mix of low
    relative horsepower, slippage, low rigidity, and bit grip.

    In even modest production you only need a pilot slightly bigger than the
    web if your drills are in good condition and you have the horsepower.
    Split points blur that line.

    This true 5 HP (5HP 3 phase motor with 7.5kw VFD) South Bend knee mill
    has definitely spoiled me.-a I've pushed 5/8 (and larger) drills though 4140HT with no pilot.-a In fact sometimes I will drill holes in a piece
    on the manual mill to allow for chip and coolant drainage on the CNC
    mill. I bought a set of the next size (1 to 2 inch plus) S&D drills just
    for use on this machine a while back.-a If you have the power there is nothing that removes material faster than drilling.-a Some will argue a bandsaw, but only if you are cutting away pieces that you could actually
    use for something else.

    I have had baby and small desktop/benchtop machines, but I've sold most
    of them.-a I still have the Taig (definitely can't broach), but the
    noname mill drill and RF30 have long since been sold.-a I am familiar
    with babying them due to low rigidity and low power.-a I do have a new
    mini mill I bought to do a video series on practical tackle molds you
    could make with a POS Mini Mill, but I've never had the time.-a Its still
    in the crate.-a Its a WEN.-a Basically a slightly better QC maybe a larger table version of the Harbor Freight mini mill.-a I would have bought the
    HF because I wanted to do the series with the cheapest mill in its
    class, but it was only available online.-a After freight costs the WEN
    was a few dollars cheaper.-a If I was buying one for real world use
    though I would go with the fixed column version from Little Machine Shop.

    I get using small machines.

    I wonder though.-a Can you lock the quill and broach with the knee?

    On a mini mill could you lock the quill and broach with the head?


    I am just chasing dust devils here. I respect that you probably know
    best how to use your machines.
    --
    Bob La Londe
    CNC Molds N Stuff
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  • From Jim Wilkins@muratlanne@gmail.com to rec.crafts.metalworking on Sat Apr 18 19:53:14 2026
    From Newsgroup: rec.crafts.metalworking

    "Bob La Londe" wrote in message news:10s0k7r$1ip4e$2@dont-email.me...

    I am just chasing dust devils here. I respect that you probably know
    best how to use your machines.
    --
    Bob La Londe
    CNC Molds N Stuff
    ------------------------------
    If my old machine tools were still competitive for making money they
    wouldn't have been available for the price.

    They are a good match to my needs, which are often fitting a new part to an existing one that may be worn or damaged. For paying jobs once I've worked
    out the prototype design by cut and try I draw up the result and send it to
    a production shop, then return to my main tasks of electronic design and assembly.

    Segway's ProtoTrak Bridgeport was no more useful on ill-defined custom work than my Clausing, and more awkward to operate when I could get time on it; I never got any on the CNC lathe. Their manual lathe was a Smithy Granite with broken milling gears, no competition to my toolmaker-equipped South Bend.

    For serious broaching I make a guide and use the arbor press, for examples pulley hub key slots and ANSI splines to fit a hydraulic motor shaft. The broach for that was more work than it was worth, I should have bought a new keyed shaft motor of lower flow rate and torque demand immediately instead
    of later. That was the belt driven hydraulic pump for my tractor bucket
    loader and I had to overload it once by turning up the pressure to get unstuck, then fix what broke.

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  • From Bob La Londe@none@none.com99 to rec.crafts.metalworking on Sat Apr 18 19:32:35 2026
    From Newsgroup: rec.crafts.metalworking

    On 4/18/2026 4:53 PM, Jim Wilkins wrote:

    I am just chasing dust devils here.-a I respect that you probably know
    best how to use your machines.
    --
    Bob La Londe
    CNC Molds N Stuff
    ------------------------------
    If my old machine tools were still competitive for making money they wouldn't have been available for the price.

    They are a good match to my needs, which are often fitting a new part to
    an existing one that may be worn or damaged. For paying jobs once I've worked out the prototype design by cut and try I draw up the result and
    send it to a production shop, then return to my main tasks of electronic design and assembly.

    Segway's ProtoTrak Bridgeport was no more useful on ill-defined custom
    work than my Clausing, and more awkward to operate when I could get time
    on it; I never got any on the CNC lathe. Their manual lathe was a Smithy Granite with broken milling gears, no competition to my toolmaker-
    equipped South Bend.

    For serious broaching I make a guide and use the arbor press, for
    examples pulley hub key slots and ANSI splines to fit a hydraulic motor shaft. The broach for that was more work than it was worth, I should
    have bought a new keyed shaft motor of lower flow rate and torque demand immediately instead of later. That was the belt driven hydraulic pump
    for my tractor bucket loader and I had to overload it once by turning up
    the pressure to get unstuck, then fix what broke.

    I've got a set of keyway broaches for pulleys and wheels. The trick
    seems to be a bunch of oil, and taking multiple passes. Start with zero shims, and just add one shim each pass. Its not to bad on any wheel's
    I've keyed.

    Now for splined shafts and bores that's a lot more work. Just more
    work. Just a lot more temporal volume of work. That's where an
    indexing plate (could just be a gear with the right number of teeth or a multiple thereof) on the spindle of the lathe to lock it and index it, disconnecting the drive from the spindle, and letting the carriage do
    all the work might help if your lathe could handle it.

    Of course you can make specialized holding and indexing tools for the
    press, but I'm not sure I would want to do that much extra work.

    Or you could just get a giant vertical slotter. LOl.
    --
    Bob La Londe
    CNC Molds N Stuff
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  • From Jim Wilkins@muratlanne@gmail.com to rec.crafts.metalworking on Sun Apr 19 08:25:01 2026
    From Newsgroup: rec.crafts.metalworking

    "Bob La Londe" wrote in message news:10s1es3$1jpuk$1@dont-email.me...

    I've got a set of keyway broaches for pulleys and wheels. The trick
    seems to be a bunch of oil, and taking multiple passes. Start with zero
    shims, and just add one shim each pass. Its not to bad on any wheel's
    I've keyed.

    Now for splined shafts and bores that's a lot more work. Just more
    work. Just a lot more temporal volume of work. That's where an
    indexing plate (could just be a gear with the right number of teeth or a multiple thereof) on the spindle of the lathe to lock it and index it, disconnecting the drive from the spindle, and letting the carriage do
    all the work might help if your lathe could handle it.

    Of course you can make specialized holding and indexing tools for the
    press, but I'm not sure I would want to do that much extra work.

    Or you could just get a giant vertical slotter. LOl.
    --
    Bob La Londe
    CNC Molds N Stuff

    ------------------------------

    That is good advice and I've done them. I bought a few keyway broaches and make the bore guides as needed, used a 54 tooth change gear to index the
    shaft to mill for the 13 spline motorcycle sprocket, and the lathe chuck
    jaws IIRC to index the brass carb jet hex sockets, broached with the
    carriage feed one point at a time with an undersized Allen wrench cutter.
    The back gears locked the spindle. Afterwards I bought an indexing wheel and bored it 2-1/4" to fit the lathe's threaded spindle, clamped under the chuck or 5C spindle thread protector.

    Although I could buy a full broach set I consider making parts like bore guides to be valuable practice in turning a plug to accurately fit an inch
    or metric hole, plus some are small enough for the job interview portfolio. These old worn machines need understanding and gentle persuasion to make
    them do what I want, and I need practice to achieve 0.001" or better
    accuracy.

    Milling the ANSI spline broach was an example of taking on a project I shouldn't have, although the broach worked, but the die cast pulley didn't hold up. I've often been on the border between buy or make which can be difficult to decide without the experience of making it once.

    I've only rarely worked production where speed mattered, in R&D usually I
    did something new, difficult and demanding once or occasionally. This is typical in my largely self-taught electrical engineering. https://www.keysight.com/used/us/en/knowledge/guides/spectrum-analyzer-buying-guide/how-to-read-a-spectrum-analyzer-like-a-pro

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