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Thread: Chicago Latrobe Screw Machine Drill Bit Review. Bittersweet

  1. #1
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    Jul 2007
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    Default Chicago Latrobe Screw Machine Drill Bit Review. Bittersweet

    Hello Everyone,

    I finally got around to posting about a set of screw machine drill bits that I bought last fall. I purchased them from Amazon.com for about $80. I had a commercial job that paid me real well and I figured that if I could skip the operation of spotting before drilling I could save a lot of time, at least for non critical locations like bolt holes . That turned out to be the case and the bits easily paid for themselves in time savings on that job alone.

    When I started using them I was very impressed with the quality. Very bright ground finish. They cut cold rolled like butter, sharp as can be. Then one day as I was drilling a 25/64" hole I noticed what looked like clearance around the bit. Pulled the bit out and checked it with a caliper and it measured about .410". Sure enough I dropped a 13/32 bit into the hole and it was wobbly. Fortunately the hole was a clearance hole for a 3/8 screw so it wasn't a big deal but if it had been for a reamed hole I would have been screwed.

    Next time I used one of the bits I checked the hole and it was oversize too. Pretty much all of them drilled anywhere from .010 to .040 oversize. How a USA based company would let crap like that out the door is beyond me. The label says USA on it. It isn't like these were ground by hand. I could almost understand if one bit was off but the whole set? These folks are making harbor freight and the Chinese tools look better all the time.

    I looked for quite a while before I could even find a contact for Chicago Latrobe and called them to explain my problem. They told me to send them back to Amazon for a refund or exchange. By that time I had sharpened probably 1/3 of them and didn't want to take the time to send them back and possibly get another batch of crap bits so I just kept them. The person on the phone at Chicago Latrobe didn't seem to be very concerned, which kind of shocked me. Eventually I will have a set of sharp bits that drill to size, as I have an industrial sharpener that weighs about 500#.

    The set of bits:


    The label:


    Anyone else had any experience with these? We used Chicago Latrobe tooling a lot when I was still working and their quality USED to be stellar.

    Brian
    OPEN EYES, OPEN EARS, OPEN MIND

    THINK HARDER

    BETTER TO HAVE TOOLS YOU DON'T NEED THAN TO NEED TOOLS YOU DON'T HAVE

    MY NAME IS BRIAN AND I AM A TOOLOHOLIC

  2. #2
    Join Date
    Sep 2011
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    Belgium
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    Quote Originally Posted by bborr01 View Post
    ... the bits easily paid for themselves in time savings on that job alone.

    When I started using them I was very impressed with the quality. Very bright ground finish. They cut cold rolled like butter, sharp as can be. Then one day...
    I don't mean to be flippant, but if the drills had already paid for themselves, do you honestly have much to be disappointed about? Drills are perhaps best regarded as consumable, not durable, tools. You also don't mention how much use they had seen - wear is inevitable...

  3. #3
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    Wear is inevitable sure, but drills don't just magically start drilling oversize unless they are not properly heat teated and come untwisted (excluding bad grind).

  4. #4
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    Is the problem that the tips are not evenly sharpened from the factory?

  5. #5
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    Hi,

    Just my personal observation, but I've felt their quality has been slipping a bit over the years. Don't misunderstand, I think they are fine even today. But I think the wide availability of cheaper "good enough" drills has led to pressure to compete against cost. Which has led a drop in overall quality at times.

    I wouldn't get overly excited about +/-.010, (it is merely a drill), but .020" is a bit much.

    dalee
    If you think you understand what is going on, you haven't been paying attention.

  6. #6
    Join Date
    Sep 2010
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    Look at the top of each drill. Do they look like this? The three lines should run parallel to each other.
    If they do - the drill is sharpened correctly.

  7. #7
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    On the Oil Coast,USA
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    C&L quality has slipped in grinding,the points have a weird cam grind on them,once reground they improve.

    I quit buying C&L and Cleveland Twist Drill because quality slipped,C&L on their grinds and CTD because they moved a bunch of stuff to Mexico and kept the US made price.

    I typically buy PTD brand when I need a good bit now,but most times use the production grade imports sold by the usual suspects.My advice is invest in a good drill grinding setup,or buy a gauge and practice free handing them YMMV.

  8. #8
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    SF bay area, CA
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    Your drill aren't split point. So they aren't guaranteed to start on center. Did they start drilling on size after you sharpened them yourself? I have also found myself to drill oversize / bellmouth holes when I don't have the drilling parameters quite right, or not enough lube.

    Also, PTD drill are made in Brazil these days and aren't as good as the USA ones. FYI.

  9. #9
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    Jan 2004
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    Missouri
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    Drills drill oversize for several possible reasons.

    Prime among them is "ground with unequal lips". Even if the "three lines" are parallel, that doesn't mean the lips are even, although you may be able to detect the error if large enough, by eye.

  10. #10
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    Quote Originally Posted by Euph0ny View Post
    I don't mean to be flippant, but if the drills had already paid for themselves, do you honestly have much to be disappointed about? Drills are perhaps best regarded as consumable, not durable, tools. You also don't mention how much use they had seen - wear is inevitable...
    They paid for themselves after I sharpened them. I was lucky that I didn't have to scrap the parts that I was making with them.

    If I was the management team there is no way I would let crap like that out the door. They drilled oversize brand new. As I said it was bittersweet.

    Brian
    OPEN EYES, OPEN EARS, OPEN MIND

    THINK HARDER

    BETTER TO HAVE TOOLS YOU DON'T NEED THAN TO NEED TOOLS YOU DON'T HAVE

    MY NAME IS BRIAN AND I AM A TOOLOHOLIC

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