drilling Alu.

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Hey whats up guysso at work i have been working with a lot of Alu. lately. I find that i have to drill some holes from time to time. I have been using my really nice and sharp metal drill bits, but find that the Alu. dulls the bites after a few holes. So my question is, is there bits made just for Alu. and if so what are they called and where can i get them? Money dose not matter as work would love to buy them for me. thanks for the help..Sean
Reply:My favorite for alum is the old Black and Decker Bullit drills. They leave little or no burr on the back side, and they don't walk on curved surfaces. They don't last long on steel though. So I only use for alum.Weld like a "WELDOR", not a wel-"DERR" MillerDynasty700DX,Dynasty350DX4ea,Dynasty200DX,Li  ncolnSW200-2ea.,MillerMatic350P,MillerMatic200w/spoolgun,MKCobraMig260,Lincoln SP-170T,PlasmaCam/Hypertherm1250,HFProTig2ea,MigMax1ea.
Reply:Dull bits are usually the result of poor drilling technique, often running the wrong RPM or surface speed. Big bits need to be run slower than small bits to maintain the same surface speed, and differing materials need different surface speeds for the same size holes. I frequently see guys simply chuck up any old bit and run it at max speed, then wonder why it gets dull fast. A good machinists manual like Machinists Handbook, will cover drill speeds in materials. It may also cover suggested drill angles for different materials. One drill bit angle is not right for every material. Also not using or using the wrong coolant/ lube can often make a huge difference..No government ever voluntarily reduces itself in size. Government programs, once launched, never disappear. Actually, a government bureau is the nearest thing to eternal life we'll ever see on this earth! Ronald Reagan
Reply:As above, But also keep a nice steady pressure as you drill, Drill bits like to cut not rub.Lincoln SP-170 MigHypertherm powermax 45Lorch T220 AC/DC TigButters FM 215 synergic MigKemppi 180 adaptive mig RULES ARE FOR THE OBEDIENCE OF FOOLS AND THE  GUIDANCE OF WISE MEN.
Reply:As above! Slow down and use some type of lubricant. Your bits may not be dull. They may have aluminum galled onto the cutting edges. The lubricant will help prevent galling. Did I mention use lubricant?
Reply:how can you say slow down when you don't know how fast he was turning, drill diameter, aluminum or al/alloy, etc.   aluminum drilling speeds are two to four times faster than steel.  some other problem here,  something omitted by op.   maybe he's sharpening his own bits.
Reply:http://littlemachineshop.com/Referen...tingSpeeds.php
Reply:I don't see how you could possibly dull a high speed steel drill bit cutting aluminum.  Is it gumming up with aluminum sticking to the cutting edges?  Saw wax or if you don't have parraffin canning wax rubbed on the bit every once and awhile will help the cutting action and prevent metal pickup.
Reply:Some aluminum alloys are very abrasive some have high silicone contents  When we would turn a lot of aluminum parts it would dull carbide lathe bits and milling bits Grant you it took awhileThe company had ceramic bits that we used for major aluminum workBacked my CATMA over your CARMA oops clusmy me  What would SATAN do ?? Miller Trailblazer 302 AirPakMiller Digital Elite  Optrel Welding HatArcair K4000Suitcase 12RC / 12 VSHypertherm PM-45Rage 3 sawRusty old Truck
Reply:I second the B&D  bullet points if work is paying for them and the diameter fits into the lineup, or a step drill (pilot and major diameter bit in one..not a unibit)  Also found TAP MAGIC for aluminum works well and smells like cinnamon in use rather than a nasty burnt oil smell. "Anybody can talk $h!t behind a monitor, I let the quality of my work speak for itself"Lincoln Square Wave 255 and 355 Tig Lincoln 255 Power-Mig w/ spool gun Koike 5 x 10 CNC plasma Hyd-Mech DM-10 bandsaw Ineco QB-76 NC tube bender
Reply:Originally Posted by CoupebuilderI second the B&D  bullet points if work is paying for them and the diameter fits into the lineup, or a step drill (pilot and major diameter bit in one..not a unibit)  Also found TAP MAGIC for aluminum works well and smells like cinnamon in use rather than a nasty burnt oil smell.
Reply:Originally Posted by CoupebuilderI second the B&D  bullet points if work is paying for them and the diameter fits into the lineup, or a step drill (pilot and major diameter bit in one..not a unibit)  Also found TAP MAGIC for aluminum works well and smells like cinnamon in use rather than a nasty burnt oil smell.
Reply:Originally Posted by GambleWhat's the difference between a unibit and step bit?
Reply:Originally Posted by GambleWhat's the difference between a unibit and step bit?I can't find that bit in a 3/4"  Anyone else have one comparable?
Reply:that looks like an annular cutter and a hole saw.   are those substitutions for the other b&d bit pictured?
Reply:Originally Posted by lotechmanI don't see how you could possibly dull a high speed steel drill bit cutting aluminum.  Is it gumming up with aluminum sticking to the cutting edges?  Saw wax or if you don't have parraffin canning wax rubbed on the bit every once and awhile will help the cutting action and prevent metal pickup.
Reply:How would this do?http://www.ebay.com/itm/M35-cobalt-s...#ht_1164wt_952Torchmate 2x2 CNC with Flashcut CNC controlsHypertherm Powermax45 Esab ET220i Razorweld 195 MigRazorweld 200ac/dc TigTormach 770, Tormach xstechRazorweld, Vipercut/Vipermig, SSC Foot Pedal Dealer
Reply:Originally Posted by lotechmanI don't see how you could possibly dull a high speed steel drill bit cutting aluminum.  Is it gumming up with aluminum sticking to the cutting edges?  Saw wax or if you don't have parraffin canning wax rubbed on the bit every once and awhile will help the cutting action and prevent metal pickup.
Reply:Originally Posted by fdcmiamithat looks like an annular cutter and a hole saw.   are those substitutions for the other b&d bit pictured?
Reply:thanks for all the replies guys all the tips have helped. How ever one of my vender reps got me a set of drill bits and a guild sheet on speed for drilling alu. so now I am set.
Reply:Originally Posted by shovelonThis Or this
Reply:I use Aluma-wax... Works great!!!Millermatic 251Miller Bobcat 225Lincoln 135Victor Oxy/FuelOlder Thermal Dynamics 50 amp (paid $700 with 10 sets of consumables)
Reply:Our carbide tipped metal cutting circular saw used to load up and pop the overload when cutting aluminum plate.  Where our welders come from, knowledge comes from age which means I know nothing because I am the youngest there.  I literally had to take the saw from his hands, rub beeswax up and down the cut and give the saw back to him.  He was disgruntled but came to me afterwards to ask what that amazing product was.
Reply:I use whatever I can get my hands on for drilling cutting and tapping. Save the xcess grease from a grease gun, spoiled CRISCO, good CRISCO whatever. Bacon grease if I had to but I think it has alot of acids. I add diesel/keosene to thin it down and most importantly, add 91% alchohol to kill bacteria or staff infection. Add the alchohol everytime I use it. Its also good to keep alchohol handy for cuts and slivers and stuf.I havnt tried the SKIL saw to cut Aluminum as I just learned that one.Last edited by Insaneride; 05-23-2012 at 09:35 PM.Reason: Skil saw