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.
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.
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]