Speaking of Drill Presses

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What RPM is good for drilling mild steel, no more than 1/4 probably? Maybe a little aluminum here and there. Been looking at bench top presses. Is 550 slow enough or as low as 230 then on up? I am looking at the Grizzly presses and my choice is between the G0485 16 speed press that has the 230rpm low speed, and the G7945 5 speed starting at 550rpm but is radial with pivoting heads and everything. I would rather have the second but wonder if the speed is ok for metal work. Thanks.Daniel 5:23
Reply:Depends on the size of the drill bit. Bigger the bit the slower the RPM. Depends also on the material the drill bit is made of. Also the material you are drilling.  You can spin a carbide bit much faster than a high speed steel bit. Cutting speed is determined by feet per minute of travel of the cutting tool. There are charts available that give you optimum speed for different size bits and in different materials.
Reply:If you are looking to run some large bits and hole saws the lower speed press would probably be the better choice. If not I would prefer the second like you stated you would.I have a Jet milling and drilling machine that I have used since the middle '70's. I don't remember the exact rpm range it has but it goes from really slow to pretty fast. I have never burned a bit or hole saw with it.
Reply:I did though. I didn't know the white ones weren't the same as the red ones, lol.The difference between art and craft is the quality of the workmanship. I am an artist.
Reply:That is the difference between Milwaukee and Lennox. Milwaukee is tougher. Cost more too.
Reply:What RPM is good for drilling mild steel, no more than 1/4 probably?
Reply:Find an old Chichago, they spin at about 25 rpm. We had one at a shop I worked in while I was in school. That baby would drill a 2" hole in some seriously thick stuff, all you would see was 2 pigtails coming out of the hole. I am still looking for one to replace my Delta.Disclaimer; "I am just an a$$hole welder, don't take it personally ."
Reply:Originally Posted by baddarrylWhat RPM is good for drilling mild steel, no more than 1/4 probably?