Drill Speeds and other Q's?

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When using a drill, what speeds are better for what situation?  I am normaly drilling up to 5/16 plain steel.  Is slower always better?  How much force to use? When using hole saws, or thicker material should I adjust anything differently?  When to use oil?  Does old gear oil work as a decent sub for cutting fluid, would used engine oil work?  I find that I kind of just make up stuff as I go, and with no exsperienced help around I normaly learn too late that I'm going it the wrong way.Thanks
Reply:Most normally when the chips are blue..too much speed..Gear oil and drain oil..... There is a reason cutting oil is called cutting oil..It aids in the cutting process..Gear and drain oil are lubricants that promote lubrication against galling and siezing...Get some canning wax and try that on your drills..I use it on everything from drilling and tapping to lathe work and grinding.....zap!I am not completely insane..Some parts are missing Professional Driver on a closed course....Do not attempt.Just because I'm a  dumbass don't mean that you can be too.So DON'T try any of this **** l do at home.
Reply:Check for the label on the drill press with recommended speeds.Search the web for a chart/table of recommended drill speeds.The material thickness doesn't so much determine the rpms used, it's the drill diameter.  The bigger the diameter, the slower the rpms.Sharp drills (and sharp cutting tools) work better than dull ones.The best cutting fluid is cutting fluid.  Gear oil smells, unless you have some weird liking for the smell don't use it as cutting fluid.  If you have a weird liking for the smell of gear oil, then put some near you while you use cutting fluid to drill your holes.Big industrial operations and machines may use different machine parameters than smaller or 'home' machines.YMMV.
Reply:Thank you for the replys.  My drill press, which my father in law bought me for $10 rusted tight had no lables at all, but had 4 speed, 1/2 Hp motor,and thats all I know.  I will look for some charts.The best cutting fluid is cutting fluid. Gear oil smells, unless you have some weird liking for the smell don't use it as cutting fluid. If you have a weird liking for the smell of gear oil, then put some near you while you use cutting fluid to drill your holes
Reply:The feed (how hard you hang on the drill press handle) should be enough that you don't bog the motor yet enable the (sharp) bit to properly cut the material being drilled.  Without just spinning the bit in place on the material, which just means friction is dulling the formerly sharp drill bit, making heat, and possibly that heat makes the material being drilled get really-really HARD (work-hardeneing).
Reply:Still: How much pressure to apply? Do I hang off the handle, or just lean on it a bit, I'm thinking that I thought I needed to put a good bit of force on the press to get the bit cutting well, but that was probubly because I was lubricating in stead of cutting. It all make sence now!
Reply:Its simple.  If you are turning, or drilling mild steel.  360 RPM for 1" with cutting oil OR coolent.    SO, 1/2" can go up to 720....  1/4" 900 rpm.....This is with a sharp bit and coolant.  Any spray penatrating oil works well for cutting oil if  you have none of the real thing.  Kerosene is also a good one.Like Zap said, if the chips are blue, you are going too fast or need coolant.  Slower is better, but the smaller bits cut nicely with some speed. LOOK at the chips.   Uniform and continus means a good cut.  Shiney and silvery means good cut.  Small pieces "dust" means dull bit.  BLUE means WAAY too fast of a cut and your bit won't be sharp for long.If you have a 1/2 hp drill press, just load the motor some.  You will stall it if  you lean too hard on the handle.  Your machine will tell you how fast to go.Listen.  Squealing means you need some  coolant or cuting oil.  You are probably going too fast and the bit is probably due for a sharpening.If you are drilling a big (1/2" or more) hole, drill a piolet hole first.  This will speed up the process and help the bigger bit do its job.  Probably a piolet hole 1/2 or 1/3 the size of the final hole.Hope I helpedDavidLast edited by David R; 06-18-2007 at 10:36 PM.Real world weldin.  When I grow up I want to be a tig weldor.
Reply:Thanks alot for the replies. I've been using TAP MAGIC (along with oil, but that will be no more), is that a good brand for cutting oil, Is there anything alittle cheaper that will work the same.I assume the same principals work when using hole saws.  Since they have more area they are trying to remove should more force be used with them?Thanks for all the great advice.  Now I just have to wait until next month to get settled in my new house and try these suggestions out.More opinions welcome.
Reply:A handy formula is:    4 X cutting speed / diameter ( inches) = rpmFor HSS bits 100 feet per minute is maximum with flood coolant.  You reduce speed if you cannot flood or you are drilling deeper holes.   I run about 70 FPM with coolant and can run all day on the same bit.  As mentioned watching for colour on your chips is a warning.   100 fpm for mild steel     50 fpm for hardened steel and stainless.    300 fpm for aluminum      200 fpm for brass For example cutting steel with a .25 inch bit gives you 4 X 100/.25 =  1600 rpm   That is maximum speed!  I am conservative and cut it to around 1000.  The quality of the high speed steel drill bit also has an influence.  Some cobalt high speed steels allow as much as 200 fpm on mild steel.  You discover if you are going too fast quickly when the bit dulls.
Reply:Originally Posted by lotechmanA handy formula is:    4 X cutting speed / diameter ( inches) = rpmFor example cutting steel with a .25 inch bit gives you 4 X 100/.25 =  1600 rpm   That is maximum speed!  I am conservative and cut it to around 1000.
Reply:Originally Posted by David RI never heard of figuring speeds that way, and I even took a course in machine shop.  I like it.  Thanks.David
Reply:Here's a handy chart for both different size bits and different types of materials(aluminum,stainelss, cast, ect). Should help you out. http://members.home.nl/b.ollivier/ht...speedchart.htmLatest Toys Miller 180 Mig and Elite Mask!!Wright Welder 225ACShop OutFitters 20/20 Bending SystemHypertherm 380 Plasma30 Years of Sparking (Electrical & Welding)
Reply:evryone talking about drill presses. how do we know he wasn't talking about a good ole hand drill. i do most of my drilling on the tractor, kinda hard to get a press up there. most of these new drill come with variable speed triggers. but t_oad, look at the chips like stated earlier, they tell the tale. and for the love of all things holy, don't try to drill 3/4" AR500. some things are meant to be burnt."Retreat hell, were just fighting in the other direction"Miller Trailblazer 302, Extreme 12 VS, Dimension 400, Spectrum 375, HF 251D-1, Milermatic 251 w/ spoolgun  Hypertherm 1000Lincoln sp 1702000 F-450 to haul it