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jeepinmatt That was a pretty good explanation. If you run it too fast and push too hard, you'll work harden the material. Not so much of a concern on a low carbon, mild steel. A36 is a very common material and very easy to work with. Once you get up to A514, T1, or certain alloys, they'll work harden quicker than a cat can like it's ass!
Like you said with carbide, we triple the spindle speeds in most cases. A very easy to remember formula for speed is 3.82 x surface speed/diameter. More often than not, we'll use a surface speed of 80 fpm. If you do the math, 12/pi is 3.82, so it saves a step and that short formula was constantly pounded in to our minds when we (myself and the 3 guys I work with on night shift) were in school.
Seeing that you used a 1" drill in your equation, I'll do the same. 3.82x80/1= 305 rpm. Not a lot of difference and it usually doesn't matter if you're using a hand drill because most aren't very adjustable.
If you have a drill press, you can feel the bit doing the work with slight downward pressure once you get your RPMs right. Another tell tale sign are the chips the drill is putting out. You want them to be somewhat short and curled, not long and stringy or really small, sharp, and a burnt blue color. To get your feet rate (if applicable in a milling situation) you would take your 305 rpm and multiple it by the desired IPR (inches per revolution). For a 1" and larger drill, it's about .015-.025. I usually go easy drilling stuff at work, so if I was using a 1" HSS drill it would have these feeds and speeds:
305 rpm and a feed of 4.5 inches per minute. I'd probably use a lower feed rate though, a 1" drill would use up some horsepower.
If you ever get your hands on CNC or even manual milling equipment, you almost feel like hand drilling something is just archaic, cave man stuff! We also have some pretty badass drills at work. The Kaiser drills we use have an inner and outer coated carbide insert and we have them ranging from 1" to 2.5". I can bury the 2.5" drill in a 4" thick steel plate and make some serious chips! It would run something like 740 rpm at 4.5 inches per minute. We also use Sumo-Cham drills made by Iscar. Those little bastards are awesome! They have a replaceable carbide tip that just twists in and they use a surface speed of 350 inches per minute. A 1/2" Sumo runs 2674 rpm at 24 inches per minute.
If it's any indication of how fast some of these drills are, they are the fastest means we have (where I work) of removing material. If I had to cut a hole in the center of a plate, most of the time we'll drill out at much as we can and then finish with some other tooling like a carbide end mill. Plus, it helps extend the life of the end mills.
Sorry for the lecture
I just like talking about machining and metal work!
