I can run that old Delta up to 4000rpm, what would you recommend, 1000?
I'm probably going to scrap today's blade and try again tomorrow. Note to self- wear a hat, sparks in hair hurt!
IMHO, and this is all it is, my opinion, 700 rpm is
much,
much too fast for a .218 drill using a manual drill press in high carbon steel. Slow it down to ~ 300-350 rpm. Pecking your drill will help too. Not only will it break the chip, it also helps to reduce heat build-up that occurs when pushing the drill straight through the material. Slow your RPM down to about half of what is recommended on generic drill charts(usually based on drilling mild steel)(and IMO, still, too fast) and peck, peck, peck..... in increments of ~ .020-.030, for every hole that you drill. Use a little bit of cutting oil and I promise you, your drill bits will last longer, and your holes will come out better. Promise.:thumbup: The pecking trick really comes in handy when drilling very small diameter, deep holes. Again, reducing heat build-up and breaking the chip/cleaning chips out of the deep hole where built up chips can cause big heat problems and binding from chips, which, inevitably cause drill breakage.
For some reason (and I'm not directing this towards you but to young apprentices I've worked with) when guys have problems with drilling, whether it be a work hardened half drilled hole, or just tough material, the first reaction is to speed the drill up. Do just the opposite to successfully finish the hole. Slow it waaaay down, especially in the case of a work hardened hole, and I mean waaaaaay down,
like less than 100rpm, add a dab of cutting oil and a little more pressure at first to get through the tough skin and you will be able to finish the hole.
Go slow, use cutting oil, and peck when drilling high carbon steel
