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  • Letter size drills

    I'm going to buy a set of el-cheapo drills tomorrow at Harbor Freight , and I have to decide whether is it worth paying $8 more for a set that includes A-Z letter sizes, or a set without the letter sizes. Both sets include 1/16th-1/2 by 1/64ths and wire gauge 1-60. I'm thinking I should just get the full set including the letter sizes, but I've never had a use for letter sized drills. What are they used for?

    -Pete
    I just like to make stuff.

  • #2
    Look at a tap drill chart and if you still have this question take up another hobby.

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    • #3
      Drill chart http://www.carbidedepot.com/formulas-drillsize.htm
      Location: Saskatoon, Saskatchewan, Canada

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      • #4
        Making letter size holes. Different tap sizes, T for a 3/8-24 form tap for example.

        clearance holes. F for 1/4".

        Drilling holes that will then be reamed, U or W for a 3/8 reamed hole.

        Millions of uses(most involving drilling holes).

        Now, the $8 for the extra 26 drills, maybe 25 since an E is a 1/4, thats another issue.

        Some of those cheap sets are BAD, real BAD. You may luck out, but I would still pop the extra $8 to have the extra drills.

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        • #5
          Yeah, I think I kinda sent out the question a bit early... should have done a bit of googling. I've not done much tapping over 1/4-20.

          I'm going to get the full set.

          -Pete
          I just like to make stuff.

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          • #6
            An upside to getting the full set is when you replace individual drills then you have an index for them already.
            scariest thing to hear " I am from the government and i am here to help"

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            • #7
              Originally posted by Alguy
              An upside to getting the full set is when you replace individual drills then you have an index for them already.
              I think everybody has probably been either tempted to buy, or bought a cheap set of drills, and yes at least you'll get a decent drill index out of the deal.
              Unless you hardly ever use a drill bit, do yourself a favor and spring for the next level up if at all possible.
              If not you'll appreciate the difference when you buy replacement bits one at a time. And yes, you will be buying replacement bits.

              -
              Home, down in the valley behind the Red Angus
              Bad Decisions Make Good Stories​

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              • #8
                Generally, most of my drills get pretty light use, but I seem to spend more than seems necessary buying specific drill sizes for one-offs, when I trot down to the hardware store on a Sunday afternoon. The thinking for this set is to get a pretty complete size range for not much cash, and replace often used drills with better quality when needed.

                -Pete
                I just like to make stuff.

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                • #9
                  Sometimes with these cheap sets there is an option for coated (some variation of Titanium Nitride) and un-coated. I'd go for the uncoated, I've often found them to be better quality and much less likely to flake on the cutting edge.
                  Paul Compton
                  www.morini-mania.co.uk
                  http://www.youtube.com/user/EVguru

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                  • #10
                    As stated, the answer is "Yes!"
                    Russ
                    Master Floor Sweeper

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                    • #11
                      Hi,

                      I had a 115 piece set of the cheapies, and wouldn't reccomend it. I had trouble tapping some small holes that were drilled with the cheap bits, and couldn't figure out what was up. Ended up measuring the bits, and all of the smaller sizes were way off. Most all of them didn't cut or hold an edge well, either. Ended up buying individual top quality sets of fractional, letter, and number bits, and haven't looked back.

                      John

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                      • #12
                        Some of the el cheapo sets aren't just bad, they are unusable. If you can see the pointy end of the smaller bits look to see if the cutting edges are of equal size on every bit. If any have eye visible defects then give it a pass because there will be more.

                        In general with cutting tools it is impossible to save money by buying lower grades.
                        Free software for calculating bolt circles and similar: Click Here

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                        • #13
                          I've had bad luck and excellent luck with cheapie drills. In general I think Harbor Freight quality has gone up. Whenever I need to drill a hole "about this big" I grab a letter drill so that they get some wear and I don't have to sharpen fractionals as often.

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                          • #14
                            People always ask me why I have such cheap *** drill bits.

                            I tell them the truth. I say "it's because they are the only ones you are going to get every time you ask to 'borrow' one"...

                            (The GOOD ones stay locked up.)

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                            • #15
                              I do a lot of tapping so a full set of fractional, number, and letter size makes sense.

                              But if you have a good idea as to what you will be using, buy a few quality bits at a time until you have what's needed.
                              Quality bits are a treat to use, they drill nicely, stay sharp longer, and the holes are of proper dimension. Unless you get lucky, all of the attributes of quality bits will be traits you won't find on cheaper sets.
                              I've seen sets whose cutting edges were ground off center and were also so crooked that they would not even roll on a smooth surface. This in addition to all those other undesirable characteristics mentioned before.

                              So if you if you do buy a cheap set at least you will know what to look for and what to expect.
                              But if you'll notice, there is a trend developing in responses. These are people who have made the same mistake you are about to. And like me have found that the cheapest set is the one you only buy once.
                              Home, down in the valley behind the Red Angus
                              Bad Decisions Make Good Stories​

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