This is going from bad to worse. I always thought Hout manufactured the HSS drill bits. Apparently they just make the storage cases.
So now even I’m wondering what drill bits are inside my Hout drill index. The tool supply place they were likely bought from is no longer.
Geez, this is embarrassing. I really hope nobody else ordered from that link.
Not either of the above, but I’m learning about these things from my recent dabbling with machining.
For the stuff most of us work with (wood, plastic, aluminum, brass), High Speed Steel should be fine, in fact carbon steel should be quite adequate unless using a Dremel, and even them most likely only an advantage if drilling steel.
The primary advantage High Speed Steel has over carbon steel is being able to take high heat from drilling without losing its temper. High Speed Steel will retain its hardness even when starting to turn dark red from the heat, while carbon steel would begin to soften at that point.
There is some potential of getting to that point with a dremel in hard material, but none of us are going to get there with a pin vise… at least not without a few thermos’ full of coffee. [:)]
Cobalt and Carbide are overkill for most of us and really intended for production work. High Speed Steel tooling is generally considered well suited to use with mini-lathes and mills. Carbide doesn’t even start to provide an advantage until you are getting into larger (1/2 ton +) lathes and mills cutting steel and more exotic (and harder) materials.
High Speed Steel will stay sharp longer than Carbon Steel, and Cobalt will stay sharp longer than High Speed Steel which is an advantage, but where a HSS drill set will typically only cost 10-20% more than a Carbon steel set, Cobalt will often cost 2-3x as much.
Don’t feel bad, I know that wasn’t what you meant to post, but I didn’t know you could buy the those metal drill index boxes empty. That might actually prove handy for me.
Aaron, that is a very good overview on drill bit types, and if I were grading you, you’d get an A+. Thank you for taking the time.
That said, I’m also interestested in hearing from anyone who can explain why those tiny carbide bits don’t snap off everytime.
And thanks for accepting my mea culpa on the drill bit box too.
I have used a few of the sets mentioned here.
One set is the one that comes in an oval, dome shaped bit holder.
Another is the set that comes in in the flat dispenser type holder (blue plastic).
Be careful when buying the second one as some are carbon steel and some are High speed steel.
Both of the sets I have are high speed steel and are sizes #61 (.039") to #80 (.0135").
I have purchased replacements for bits that I have broken from MicroMark that are high speed steel and come in packs of 6. These seem to be a pretty good quality.
The Carbide set was 10 pieces and has only 5 sizes from .8mm (.0315") to 1.0mm (.0395"). I suppose there are other carbide sets out there with different sizes.
In use, the High speed steel sets are “jobbers length” and range from .780" in length, to 1.575" long. Because of the very small diameters, they tend to be kinda flexible, but brittle enough to snap if bent too much. I try to chuck the bit in a pin vice so that just the tip of the bit shows through the material I’m drilling, keeping the exposed part of the bit as short as possible and still allow me to see what I’m doing.
The carbide bits are specialty bits, I think, designed for drilling printed circuit boards and such, so the need for length is not great. The “twist” part on mine is only about .275" long. The rest of the bit, the shank portion, is .125" in diameter and about 1.050" long, allowing for a good grip in the chuck. There is a plastic ring pressed onto the shank, apparently used when installing the bit in CNC drilling equipment to control the depth and keep them uniform.
The result is, that to me, the carbide bits, even though more brittle than the high speed bits, seem to be a little more resistant to breaking because of the shorter length of the twist, the tendency to run in the larger diameters and the hardness of the carbide. Regardless of the bit you choose, a light touch and a tecnique that keeps the bit from bending is the key for these tiny things. If you have a model makers drill press, that helps a lot if you are drilling a lot of holes at a 90 degree angle to the work. I have noticed that the ground finish on the carbide tips and flutes are significantly smoother than most of the high speed bits in the micro-number range I’ve seen, although I’ve drilled wood, plastic, copper, brass (photo etch and mini bar) and even stainless steel photo etch with both carbide and high speed bits. I’ve broken a few, heck I’ve even broken 1/2" diameter cobalt bits doing construction work and steel fabricating.
I did buy a set that came in a steel, mini drill bit holder that looks like full size holders, but I found I had a bit of difficulty getting the bit I wanted out of the thing. I found I like the plastic dome one the best, kept on the bench and the flat plastic dispenser holder second, kept in my carry tool box and one on the bench. The carbides usually come in a type specific holder or individually in little plastic tubes with a cap on them. In the end, many of mine wind up loose on the bench or in my carry tool box, requiring a digital caliper to find out what size it is as none of these little bitty things have the size on them.
Hope all this helps. None of these sets are really expensive, so, in my case, I’ve tried them all. Find out what works best for your hands and go with it.
EJ
EJ, thank you for sharing your experiences regarding the drill bits. It is appreciated.