Bits for drilling 1" plate?

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The current buts I have are going just far enough into the steel to make a dimple then nowhere. Anyone have recommendations for drill bit brands and types? Also is high speed oiled better or low speed oiled?Victor Journeyman OA TorchVictor Edge RegulatorsLincoln 180HD (240v) MIG/FCAWShark LT v7 CADMiller Digital Elite Helmet35 Milligrams of Insanity
Reply:The problem is the tip.  Try poking a hole with a new 1/8" or 3/16" bit first.  Smaller bits have smaller tips which means they cut closer to the point.  Bigger bits do virtually zero cutting at the tip, that's why you only get a dimple.  Split point bits will do better than normal ones, but I'd still recommend a small pilot.My name's not Jim....
Reply:Hole saw bit. Clamp down the workpiece, and go to town. I have drilled as many as 10 holes in 5/8" L angle material with one bit. Beats a 2 fluted regular bit every time when drilling manually.And then, after so much work...... you have it in your hand, and you look over to your side...... and the runner has run off. Leaving you holding the prize, wondering when the runner will return.
Reply:i always start with 1/4 in and increase in 1/4 in increments until you get there for whatever size you need at the time.Dynasty 200DXPassport plus w/ spoolmate 100victor 315c oxy/(act and prop)Miller digital elitemilwaukee power tools
Reply:I'll also toss in anular cutters. Sort of like high tech hole saws, they are usually the choice for doing large precision holes in steel using a mag drill or mill. They are not cheap, but blow the doors off twist bits and hole saws if you've got the right tools to run them..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:He never said how big of a hole.  Just 1" plate.  I do use holesaws frequently for holes over 5/8".My name's not Jim....
Reply:Just remember to keep the rpms down so you don't burn up the bit.  Also you did not say what tool you are using to drill with, drillpress clamp down securely and if by hand just hold the drill so if it catches you dont sprang your wrist.
Reply:Buy/rent a mag drill with annular cutters and you will never look back....or be the same. 20 seconds or so per hole in 1" plate is nothing to sneeze at.QamuIs Heg qaq law' lorvIs yInqaq puS
Reply:I have a rigid drill press and I am trying to cut 1//2 inch holes in the plate. I will try sizing up slowly. Do you use wd40 ? I would love to have the cash for the mills and other fun tools but alas I am only a working stiff. Victor Journeyman OA TorchVictor Edge RegulatorsLincoln 180HD (240v) MIG/FCAWShark LT v7 CADMiller Digital Elite Helmet35 Milligrams of Insanity
Reply:1/2" or 1 & 1/2"?My name's not Jim....
Reply:You can buy an adapter for annular cutters so they can be used in a std. drill press, IIRC. For what you are about to do, it would be the best way...esp if you have a ton of them to drill. On a press, they will drill tons faster and cooler due to the hole saw type design they have. Here's where I get my cutters. http://www.clevelandsteeltool.com/cutters.asp FWIW, I have a few cutters that have punched over 50 holes in anything from 1/2 to 1" and are still running strong. These guys will even sharpen them if you want. You will most definitely need to be running coolant. I run LPS Aquacut in my stuff. Works great and smells like cinnamon.  http://www.lpslabs.com/product_pg/cu...g/AquaCut.html  Enco sells it pretty cheap in gallon jugs. It even makes my tiny 8" Clarke DP act like a big boy.QamuIs Heg qaq law' lorvIs yInqaq puS
Reply:Get a drill doctor. relatively cheap.
Reply:Originally Posted by DDA52You can buy an adapter for annular cutters so they can be used in a std. drill press, ..... :
Reply:also, what RPM's are you running on the drill press?  What drill bits are you using?I would keep the RPM's down to less than 300 (max) and use nice high quality drill bits (I prefer Norseman bits which are available at Fastenal).  Use a good cutting fluid to ensure clean chip ejection (boelube is what I use, but there is a plethora to chose from).  Retract the bit relatively often to make sure you aren't filling it up with shavings, make sure you have a decent amount of pressure on it as well (it shouldn't be sliding along the metal and taking it off in little tiny shavings, it should be actually cutting the metal).Of course, as others have said, if you have access to a mag drill and anular cutters, it'll go through it like butter...but those are expensive toys.--Wintermute"No man's knowledge here can go beyond his experience." - John Lockewww.improvised-engineering.comManufacturer Agnostic:Blood----------Sweat---------Tears----|------------------|----------------|----Lincoln Red, Miller Blue, Esab Yellow
Reply:DDA52 is right about the annular cutters being fast but the set up is expensive. for what you are doing any quality drill bit should work just fine. Just reading between the lines the drill is probably running so fast the bits are burning up or wern't sharp whenthe hole was started. You should be able to chuck up any decent 1/2" bit and drill a hole with no problem with the right speed.
Reply:Originally Posted by RellsI have a rigid drill press and I am trying to cut 1//2 inch holes in the plate. I will try sizing up slowly. Do you use wd40 ? I would love to have the cash for the mills and other fun tools but alas I am only a working stiff.
Reply:Originally Posted by rlitmanDon't size up slowly.  You'll end up with a hole that is out of round.Drill in two steps.  First size should be just under the web thickness of the final bit.For a final hole of 1/2", the first hole should be about 3/16".
Reply:Its the nature of two point cutters.  From a milling perspective, a two point cutter makes a perfect slot, because the forces are balanced, but for drilling, it wants to bias towards a trilobular shaped hole.  When stepping up, your drill bit only feels the face of the hole at two points, and wants to chatter.  Each point will intermittently grab, allowing the other point to pivot around an axis centered on the opposite cutting point instead of the quill axis.  This causes the hole to go out of round, and fatigues the drill bits.  I suppose this effect is negligible when going up to the next sized bit in a 115 bit index, but jump up 1/8" or so, and its real.The web of a drill bit doesn't cut, and so requires a lot of force to push it through.  Split point bits help in this regard somewhat.The web also exerts a piloting force as it forces its way into the workpiece, which keeps the hole more round, and stops chatter.  Ideally, you can pick a drill bit just under the size of the web, pre-drill with that, and have the best of both worlds.  BTW, your rpm's depend on the diameter you're drilling, so in a perfect world, you would use a different speed for both steps.  There are charts for this.
Reply:i pruchased a jancy mag drill and annular cutters and have been thankful for these great tools.  save up some money and go for it, my mag also swithes to a 3/4 chuck drill set up and still great......
Reply:rlitman: great input and makes perfect sense...
Reply:Ah man a 1/2 bit nice and sharp put your safty glasses on use lot's a juice and start hawging holes, esspecially with a press. I got 9/16 annulars for my mag drill and a chuck for my mill that will fit them too. Annular bits are the ticket for larger holes.Visions SteelWasilla Alaskahttp://www.facebook.com/album.php?ai...5&l=c32ed1320fwelderstourchessawsgrinders
Reply:Originally Posted by rlitmanBTW, your rpm's depend on the diameter you're drilling, so in a perfect world, you would use a different speed for both steps.  There are charts for this.
Reply:Originally Posted by BurbmanRPM's are primarily dependent on material hardness, secondarily on hole size.  If you run too fast in steel, the bit just heats up and dulls the cutting edges.  300-400 RPM is about right for mild steel.  If you don't have a good cutting oil, use 3-in-1 light oil, it's better than WD-40 for jobs like this.
Reply:Remember that slower SFPM isn't necessarily a bad thing.  Faster is.  I drill at around 300 RPM with a 1/2" bit since it keeps my bits lasting longer and since I don't have a coolant system, it keeps the bits from getting too hot.--Wintermute"No man's knowledge here can go beyond his experience." - John Lockewww.improvised-engineering.comManufacturer Agnostic:Blood----------Sweat---------Tears----|------------------|----------------|----Lincoln Red, Miller Blue, Esab Yellow
Reply:Originally Posted by RellsI have a rigid drill press and I am trying to cut 1//2 inch holes in the plate. I will try sizing up slowly. Do you use wd40 ? I would love to have the cash for the mills and other fun tools but alas I am only a working stiff.Never use motor oil for cutting; we don’t want to lubricate anything. WD-40 is out too. Use cobalt drills.
Reply:r u kidding me..........i've been using the same 1/2 drill bit in my milling machine for years.......using MOTOR OIL to keep it alive..........it's not kobalt it's regular HSS.        thermal arc 252i  -  millermatic 350P -   miller XMT, cp300ts, 30a 22a feeders, buttload of other millers, handfull of lincolns, couple of esabs  -   Hypertherm 1250 G3
Reply:Kidding! No! Cutting oil is formulated for cutting; the additive package is for cutting/cooling, learned that in shop in 1952.  I have a few things i know HSS drills will never cut into.
Reply:I would just grind a back cut on the bit. A half inch bit will just blow right through steel. Sometimes I use a half inch hole to pilot a larger bit. Some guys grind a little drill bit right onto the larger bit. I don't do that. But it is an option. Dewalt sells them. But a back cut works best. New York Twist drill puts a sweat back cut on some of their bits. It just blows through metal. If I get a chance I will pop a half inch hole and video tape it. And show the back cut on the drill. You can put it on any drill in about ten seconds with a grinder. If I have to use a drill with a hand held motor. Sometimes I put a back cut on the larger bits too. Actually stepping up in drill size causes a very snug round hole. Not an oblong hole. You will get an oblong hole from not having pre drilled. Allowing the bit to walk around on its point, instead of being wedged into the pilot hole. If you are over heating you can cut hard, and pull back. Letting the drill bit re-harden and the work soften.        Sincerely,             William McCormick
Reply:Sulfurated oils are usually the oils used in cutting. Sometimes called rape oil.They work well. I usually only use oil if I am in a hurry, or deep drilling. Sometimes in critical parts that I cannot afford to break a bit or tap off in. But if you are using a very high speed press or hand drill, you can harden the soft steel you are cutting by using that oil. I had it happen. It was similar to stainless steel becoming to hard to drill. It set me back a little. Got a laugh out of it. It took me two new bits to break through. Pipe threading oil like you get in a plumbing supply shop is a sulphurated cutting oil. By hand you can drill half inch holes in steel rather easily though with a back cut. Or with a pilot hole.        Sincerely,             William McCormick
Reply:We always called it a back cut. But the technical term is split point. I did some research. I have been grinding them for years. But back cut, is what we always called it. All of this is with no oil. I drill thousands of holes and never use oil. It is unhealthy to breath it, expensive, messy and it makes your skin soft so you pick up sharp cuttings and scream like a women. With a magnetic drill press, I can drill faster then with a core bit. If I was doing stuff in a machine shop to very tight tolerances, I would get out the cutting oil, with low rpm's. In the movie, I drilled right through a half inch plate with a hand held drill motor, using a 118 degree, split point drill, with no extra side handle on the drill motor. That plate was just being held from spinning by a little "C" clamp onto plywood. I then spun up my drill press, so I could figure out why he was having a problem. He is probably going to fast. But you can see that in the movie. When I slowed it down some I could make a hole. But that is still about four times faster then I usually spin up the drill press. But I was trying to match a smaller single speed drill press, I use sometimes. Normally I go very slow, and go right through steel. Whether it is one inch or half inch. Normally I use a magnetic drill press. A regular 118 degree split point drill. Can make about fifty to one hundred holes between sharpening. A good 135 degree cobalt bit, can maybe do a few more between sharpening. On an industrial drill press you can load the spindle bearing, and you almost do not have to hold a large piece of metal, as you drill through it. The reason is the drill just cuts to the end. The spindle does not drop at all, and so it does not screw through the part when you punch through. It is amazing to actually use an industrial drill press. Most small drill presses are made for very small bits. So they go very fast. Because small bits need to be turned fast.        Sincerely,             William McCormickLast edited by William McCormick Jr; 03-15-2010 at 06:44 PM.Reason: I had two words out of order
Reply:Tons of how to sites, knock your socks off.http://www.michigandrill.com/tech/tw...t_grinding.phphttp://www.carbidedepot.com/formulas-drills-speeds.htmhttp://www.woodcraft.com/Articles/Ar...?ArticleId=267http://en.wikipedia.org/wiki/Drill_bithttp://www.clag.org.uk/drills.htmlhttp://www.woodworking.org/WC/GArchi...7bobsharp.htmlhttp://www.gadgetbuilder.com/DrillSharp.htmlhttp://books.google.com/books?id=N9g...drills&f=false
Reply:Originally Posted by transitTons of how to sites, knock your socks off.http://www.michigandrill.com/tech/tw...t_grinding.phphttp://www.carbidedepot.com/formulas-drills-speeds.htmhttp://www.woodcraft.com/Articles/Ar...?ArticleId=267http://en.wikipedia.org/wiki/Drill_bithttp://www.clag.org.uk/drills.htmlhttp://www.woodworking.org/WC/GArchi...7bobsharp.htmlhttp://www.gadgetbuilder.com/DrillSharp.htmlhttp://books.google.com/books?id=N9g...drills&f=false
Reply:William - Thanks for the efforts you put into the video.Personally, I like water when field drilling steel.Probably not worth the bother for tiny ½" holes, (Alfred usually just punches the small holes with his sidearm ) but for drilling larger holes in thick material, low speed and a flood of water, along with an occasional shot of oil, keeps the curlicues rolling off of the bit.Good Luck
Reply:there's definately a different speed (window) for each and every size drillbit in which it cuts efficeintly and without destroying itself , then they can all punch lots of holes if ran correctly before being re-sharpnd. - dont Bore straight through without breaking or pulling up the chips.? while doing this then a drop of oil in the bore.? Not turning off the machine , allowing the bit to continue spinning to air quench (or stop it , and watch it smoke ).? and absolutely Correct speed.?my bits last forever , well , maybe 15 years sofar.        thermal arc 252i  -  millermatic 350P -   miller XMT, cp300ts, 30a 22a feeders, buttload of other millers, handfull of lincolns, couple of esabs  -   Hypertherm 1250 G3
Reply:dont mind me though.......i'm just a painter , trying to get byi like the video and listening to u guys also        thermal arc 252i  -  millermatic 350P -   miller XMT, cp300ts, 30a 22a feeders, buttload of other millers, handfull of lincolns, couple of esabs  -   Hypertherm 1250 G3
Reply:When I bore something in the lathe. I use oil for sure. But I am going two, three, four, or six inches deep. One inch deep and under I rarely use oil. It makes smoke. It smells bad.        Sincerely,             William McCormick
Reply:Milwaukee makes a nice little set of split point 135 degree bits that come in a plastic case. For about $35.00 bucks. Something like 1/16" to 1/2". Not a bad little set. The half inch drill has a 3/8" hex shank for the common 3/8" drill motors duct guys use.They really lasted like my larger expensive silver deming bits, that I use in the drill mag. I can drill a hundred plus 13/16" holes between sharpening with those. No oil or cooling at all. They take about twenty seconds to open up a 3/8" pilot hole in 5/8" or 3/4" steel. The 3/8" pilot takes about twenty seconds. Add a few seconds to change bits for each joint or flange on an "I" beam and that is not bad. I once drilled over two hundred holes in 1¼" schedule 40, stainless steel pipe with a similar bit. No oil no cooling. No sharpening for as many has 50 holes. Using the Milwaukee Drill Mag. Each hole took about 30 seconds to open from a quarter inch hole. Those bits in a good drill mag, are actually faster then some decent magnetic, core or magnetic broach, drills. They call them broaches today, but they used to be called core drills. And they had an outside bearing that the core bit fit into to keep it steady. Today they let the pilot, hold the larger broach or core bit steady. They used to use them without a pilot because of the outside bearing. They went much faster then they do now. That could beat the old drill mag and drill bit for speed. A friend of mine had a bunch of them in his shop. And he could get a city steel job for a floor or two on a building, ready in hours if he had to. But they were industrial grade core or broach setups.        Sincerely,             William McCormick
Reply:Cutting oil. NOT wd-40!!!!200amp Air Liquide MIG, Hypertherm Plasma, Harris torches, Optrel helmet, Makita angle grinders, Pre-China Delta chop saw and belt sander, Miller leathers, shop made jigs etc, North- welders backpack.
Reply:Don't size up slowly.  That will only cause broken bits and snags.1/2inch holes should be no trouble to drill, especially in a press.  Any bit will do.  If you're using standard drill bits, it would be wise to start with a pilot hole.  The pilot hole should be slightly larger than the thickness of the web of the drill.  For a 1/2 inch bit, 1/8th inch will probably be perfect.  If you don't want to deal with pilot holes, use split point bits.If you turn the bit slowly, cutting oil shouldn't be necessary in mild steel.  Just use decent quality bits, no fancy oils, no cutting oil, and you'll get decent quality holes.Don't fall for fancy names like cobalt, TiN, etc...  These are specialty metals and coatings for high speed operation and production work.  Simple HSS or high speed steel bits are sufficent for most drilling operations including stainless.  Again, buy quality HSS bits and you'll be suprised how long they last.Drilling holes isn't that big of a deal, just do it.Last edited by 76GMC1500; 03-18-2010 at 02:16 AM.
Reply:I like cobalt (not to be confused with the brand Kobalt).  It holds up better when drilling in stainless, but yeah, HSS is fine.  Just forget about the awful chinese stuff marked HSS.I've seen those with such bad heat treatment, where one bit split in the middle of the web, along the length of the bit, and another had its tip round off in brass.Also, although this doesn't make a difference when drilling shallow holes (when the depth is under one and a half times the diameter of the bit), shiny cobalt and TiN bits are better at deep holes.  Its because the inside of the flutes are smoother, which causes less friction for the removed chips, which keeps the hole from "clogging".  The black oxide coated HSS bits need to be pulled out and cleaned much more often.  Especially in wood.
Reply:Here is what i use exclusively.I got a few solid carbide for the rockwell hard stuff.Turn these slow Attached ImagesLast edited by dugndeep; 03-18-2010 at 10:28 AM.Maxus Pro-125 MigChicago Electric 90 amp DC flux-coreLincoln Electric AC 225 tombstoneO/A torchM/O mini-torch10 acres of flatland15 acres of holler