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Although I own a drill index, surprisingly I’ve never had a complete set of drill bits for it. I bought the index to house the pile of bits leftover from broken sets and other bits I inherited. As you can see in the picture below, I’m missing several bits in the middle row and most of the sizes in the largest. Although the selection of bits has served me well on most occasions, many times I’ve had to ream out a smaller hole or settle for a sloppier fit.

After not having the right-sized bit for a project for the umpteenth time, I finally decided that it was time to remedy that situation. Like all my projects I find that I usually spend at least as much on tools to complete the project as I spend on supplies. So to save money, this time I went to Harbor Freight where I found the Drill Master 29 piece HSS drill bit set with 3/8″ cut-down shanks on sale for $15.

This set is made from high speed M2 steel coated with black oxide and contains 29 bits, sized 1/16″ to 1/2″ in 1/64″ increments and housed in a metal drill index. The website claims the bits are rated 60-66 for hardness; I can only assume that they’re referring to one of the Rockwell hardness scales.

Impressions

Like most of Harbor Freight’s tools, these bits are imported. It says right on the box that the bits were made in China. Since the bits are black oxide coated, I’m confused why they decided to cover them with protective oil. You’d think the coating would prevent them from becoming piles of rust on the journey across the sea. So whenever I reach for one of the bits, I end up thinking, “eww! I really need to just sit down and clean them all up one of these days,” but when you have limited shop time, the last thing you want to do is clean.

The smaller and therefore shorter bits have very little run-out. Unfortunately I can’t say as much for the larger bits. I’m pretty sure that the bits over 3/8″ with the reduced shanks are the worst. They crudely machine the end of the bit down to 3/8″. There are still quite pronounced tool marks in the circular ridges down the shaft.  I suspect this makes it hard to get the bit tightened into the chuck perfectly straight.

Since these are cheap bits, it makes sense that they’re sharpened with only two facets forming chisel-tipped bits, rather than four facets coming to a point (see the great article on Stu’s Shed about sharpening drill bits). If you click the above picture to make it bigger, you’ll also see that the sharpening was done pretty carelessly. The manufacturer sharpened the bits with a low grit, leaving course marks, and the cutting edge is pitted. It’s hard to photograph, but you can also feel a pronounced burr on the cutting edge.

Conclusions

Even though they aren’t the sharpest bits in the drawer, they are drill bits nonetheless, and they still drill clean holes reasonably quickly. I’ve used some of the bits to drill holes in wood and aluminum and they’ve given satisfactory results. Again, the larger bits have some run-out, but just have a pilot hole or a divot from a center punch and make sure your work is secured and the bit will dig right in and produce a relatively clean hole. If you were using them in a hand drill, you’d probably never even notice the bits wobbling.

At $15 I think I got my money’s worth, but if I had to do it again I’d drop a little bit more and buy titanium or cobalt bits. They’ll last longer and you can use them on harder materials, but that’s a thought for another post.

HSS Bit Set [Harbor Frieght]

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22 Responses to A Closer Look At A Drill Master HSS Drill Bit Set

  1. mister mike says:

    I find Harbor Freight (and similar Chinese tooling) drill bits to be very brittle and the smaller diameter bits snap easily. They also seem to clog more than better brands. Perhaps they aren’t heat-treated as well as better brands. Since the majority of my work is making pilot holes in wood this isn’t a big problem and my more practical solution is to buy the multi-packs of smaller Titanium coated drill sizes and just have a quick replacement at hand.

    The best drill accessory in my shop is the Drill Doctor sharpening grinder. I can get older (made in USA) dull bits at yard sales and flea markets for next to nothing and in seconds produce a useful cutting bit.

  2. Cameron Watt says:

    I’m not one for coated bits. Any benefit is lost after you sharpen them so why not just go with HSS?

    Keep ’em sharp and keep ’em cool!

  3. george says:

    i’ve gone through the cheap route and have moved on. i now go the $$$$$$ route and know i will get what i want and get it done safely. nothing like a ruined piece or injury due to the cheap stuff. i have 3-4 sets. one cobalt, two hs sets and a damaged junk set that i use for roughing out stuff.

  4. @mister mike:

    I haven’t encountered the brittleness you talk about in the smaller bits. Since writing this I was trying to make some progress through some stainless steel (don’t ask). I used the smallest bit with enough pressure for several minutes so that I could actually see the bit flexing quite a bit, but it didn’t break. But that’s just one bit, there’s no saying that the next bit I pick up won’t snap.

    @Cameron Watt:

    I’m not one for coated bits. Any benefit is lost after you sharpen them so why not just go with HSS?

    Black oxide is what they had available in a set. I think you’re giving black oxide coating too much credit, at least on the bits I’ve used from the set. The coating is already gone from around the cutting edge and chisel point. Once used they seem to turn into just HSS bits.

    I’m sure there are better black oxide coated bits, but I’m still not sure there would be any coating left by the time you need to sharpen it anyway.

  5. Steve says:

    There is a method that will recoat in black oxide if it was needed. Its easy, but honestly, not worth the effort for cheap bits.

  6. Paul says:

    The OP wondered why they oiled the bits even though they had black oxide. Black oxide is not a very good rust proofing coat (it helps, but does not last at all). The humidity in the shipping container alone would probably start to rust the bits.

  7. Steve says:

    @Paul Thats right, I would describe black oxide as, not so much rust protection, but as reverse rust.

  8. DocN says:

    Titanium, in a home-shop type work environment, is essentially worthless. It’s a marketing gimmick, so they can plaster “TITANIUM!” on the package- and, the average buyer who doesn’t know anything about metal or metallurgy, gets visions of some super-strong exotic space-age material and will happily pay 25% to 50% more.

    First off, the drill bit is NOT titanium. It’s standard HSS- high speed steel. It’s *coated* with an extremely thin- as in microns- layer of TiN, or Titanium Nitride. That’s the gold coloring you see on the bit.

    While TiNitride is, in fact, very hard and wear resistant, it’s also *extremely* thin. In a proper industrial setting, it is NOT intended as a way to make the drill “harder” (as in, able to drill through more difficult materials without dulling) but rather it’s intended to make the drill ‘slicker’.

    That means it’s intended to help keep chips from “welding” (due to heat and pressure) to the cutting edge, and to help prevent chips from clogging the flutes.

    It does work, and it’s actually quite worthwhile… in an industrial setting, where the job is dependent on how many pounds of metal is removed per hour, and how many holes a drill can make before it has to be replaced.

    In a home-shop setting, in a hand drill press, or worse, just a plain hand drill, period, it’s worthless. It offers zero benefit whatsoever. It is quite literally nothing more than pretty packaging designed to attract the buyer’s eye. It’s a sales gimmick.

    Cobalt is not much better. Adding cobalt to high-speed steel does in fact improve the metal. Specifically, it helps the HSS hold more hardness at higher temperatures.

    The problem is, again, in a home-shop environment, it’s nearly worthless. The improved heat resistance is in the range where the bit is nearly turning red- that’s great when you’re having to drill a very tough, exotic alloy like Inconel or Hastelloy, but if you’re turning the bit red in a home shop, no amount of cobalt is going to save you.

    And the amount is the other thing- to produce that improvement in an HSS drill bit, you need something like 5% to 8% cobalt. But Cobalt is fantastically expensive, and raises the cost of materials and production. So the people who make box-store or Harbor-Freight “cobalt” drills, put in just enough to be able to *say* they’re ‘cobalt’ drills. Rumor has it, that’s down in the .1% to .05% range, which, needless to say, doesn’t actually improve the HSS any appreciable amount.

    But again, it lets the makers slap “COBALT!”- another exotic sounding space age word- on the packaging, and jack the price up another 25% to 50%.

    Do yourself a favor and stop buying the sparkly-shiny and start buying name-brand US or European-made. Chances are you’ll have to do a little more legwork than just driving to Home Depot or placing a Harbor Freight order, but it’s worth the time and money. Trust me.

    Don’t bother ordering “titanium” or “TiNitrided”, don’t worry about ‘Cobalt’, or any of that nonsense. 99.999~% of your drilling jobs will be more than adequately handled by a good quality conventional uncoated High Speed Steel bit.

    Doc.

  9. Simon says:

    At Home Depot level is the DeWalt bullet point ones – they are pretty decent for the money.

    cheap bits are not worth even the basic price.

  10. fred says:

    In our metalworking shop – having only a fractional drill bit assortment – and only in jobber length – would certainly quailify for not having the right bit for most jobs. We have sets of wire-gauge (number) drills and Letter drills in jobber, screw machine (short) and Taper or aviation lenngth to go along with tapping operations. We buy various Kennametal brands . We also buy W L Fuller plexipoint drills for boring acrylic sheet goods for security enclosures etc. We like Freud and some other carbide tipped wood boring bits in multiple spindle machines in our wood shop.These come in 57.5 and 70mm lengths. We also opt for Fuller brad point bits for woodworking operations.

  11. Toolboss says:

    My MAC Tools guy got me started on MAC branded bits the first time he told me they will warranty every bit from 1/4″ up. I later became a MAC dealer, and to this day, the warranty stands. No Drill Doctor needed, just swap ’em off when they get dull.

  12. Cameron Watt says:

    I almost never drill deep holes; mostly under 3/8″ deep. If I break a bit, I regrind a point and have no trouble using a “stubby”

    @Paul: I’ll wager that the oil is cutting oil left over from manufacturing the bits.

  13. Patrick says:

    I’ve had the brittleness factor kill some of those small gauge HF HSS bits.

  14. Jaxx says:

    I started making my own drill block holder for work, got to the point where I couldnt be bothered to get all the drill bits and size them, so I bought this set, for the tin! I will use each until they blunt and then throw them out and replace them with Trubor 8% cobalts from the works stores.

    So far these have been absolutely fine in ally, of course if you want good holes you should always drill your pilots!!!! No matter how awesome the drill bit you are using is.

  15. johnb says:

    Real dumb quest here. Why do you store your bits pointy (love these technical terms) side down?

  16. @johnb:

    I could give you some bullshit reason like I’m doing it to protect the pointy end, but in reality I just prefer storing them that way. I think I saw somebody else do it once and I thought it looked cool.

    I don’t think there’s really any advantage or disadvantage to pointy side up or down.

    I can think of one thing that might be handy. Store all your bits pointy side up when they are new or freshly sharpened, then turn them upside down after they get dull. When a bunch of bits are turned upside down it’s time to get out the sharpener.

  17. Jim says:

    If I put a bit back into the drill index upside down, it is because it has spun in the chuck, created a burr and will not fit back into the index rightside up.

    Once I knock the burr off with a file, I place it back into the index rightside up.

    That would be my guess for the practice.

    Jim

  18. ambush says:

    I don’t really like cheap bits, but the nice thing is that you have a set. Then all you have to do is buy nicer ones to replace the ones you mess up.

    Oh and slightly off topic. But nearly all consumer drills seem to have the cheapest crappiest chucks. Especially since keyless chucks have become prevalent. The first thing I like to do is upgrade the chuck to a low-mid end jacobs chuck

  19. fred says:

    Adding to what DocN says – a dull bit – improper feed rate – lack of lubrication in drilling some metals can result in some local work-hardening making the drilling process more difficult.
    We are also often drilling into difficult materials like cast iron and often don’t use drill bits at all – but use rotabroach cutters in either a stationar drill press – or magnetic drill press in the field.

  20. miss frannie says:

    Once on a tight budget I bought a set of these bits. They were ok for wood. As for steel in a drill press poor to sad to even pathetic!

  21. Billjoe says:

    When drilling steel, the most important aspect of drill selection is to stay with the 135 degree split point drills, NOT FROM CHINA! Either that, or learn to grind a split point on a new drill.

    I unknowingly bought split point drills that turned out to be from China, and they would not cut until I reground them. The material is not as important as the grind, and the split point is far beyond any other method of drill sharpening. it requires decent eyesight or magnification, good light, the right grinding wheel and dresser, and an understanding of what the split point should look like, but any other drill point is a waste of time on steel. Might make a hole, but it could be 99% easier and faster with the right grind.

    I have ground over 25000 drill points in my life for industry, with 100% satisfaction, so I’m pretty sure I know what I am talking about…..Joe

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