Drilling large holes by hand/bit recommendations

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Hi all,I'm working on a project now that will require me to drill holes of one inch diameter (possibly larger) into 1/8" and 1/4" mild steel.  I don't own a drill press so was planning on doing this by hand, but considering that I've never done anything larger than 1/2" in metal, I'm wondering if I may run into any trouble?Second,  I'm wondering if anyone can advise me on some good drill bits that come in large sizes (1" and larger).  I haven't seen any at hardware stores or my local home depot and the only one I found online is this: http://www.amazon.com/gp/product/B000CSSG1U , of which I'm unsure the quality.  Thanks!-Z
Reply:If you're going to drill a 1" hole by hand, you'll need to do it gradually.  Center punch where you want to drill the hole, and Start with a smaller bit (I'd start with 1/8" for a pilot hole, and work your way up.)Another thing you can do is burn the hole with a torch, or take it to a shop and have them drill it for you.  I'm not sure where you can find a 1" bit for a hand drill.  Good luck!
Reply:I typically do that anyway for smaller holes, but what would worry me here is that it will be near the edges of the workpiece, thus requiring the punch to be incredibly accurate (unless I buy a gigantic punch).  I wouldn't burn it with a torch, as it needs to be clean, but I may consider taking it to a shop as I imagine it would be quite cheap.
Reply:I second the 1/8 as a starter bit...  might want to check in on a uni-bit / step bit...  Or a hole saw if the holes to not have to be precision drilled... 1" drill bits are quite expensive...
Reply:Get yourself a few GOOD holesaws.  Use plenty of  coolant and you will be fine.I'm a Lover, Fighter, Wild horse Rider, and a pretty good welding man......
Reply:Well, it does have to be precise enough to fit over 1" threaded plumbing pipe.  I don't know if a step bit is a good idea for this...would a holesaw be precise enough?  And would it even make it through 1/4" steel?
Reply:The fluted bit will not always cot true holes, it depends what you have to chuck it in.  I would use metal cutting hole saws (carbide)http://www.lenoxtools.com/enUS/Produ...LE_CUTTER.htmlor Step Bits...http://www.lenoxtools.com/enUS/Produ...RILL_BITS.htmlEach will cut a nice clean true hole.Me!
Reply:for holes that large I would use a hole saw because I have them. If I didn't I'd see about renting a mag drill.
Reply:There is no question that I would rent a mag drill.  You can rent the drill for approx $50-65/day and you have to buy a pilot ($8) and a 1" cutter ($50ish).  You can drill a 1" hole is 1/4 plate in less than 10 sec.  I guess it depends on how many you have to cut I guess.
Reply:I'd use a good bi-metal hole saw, I just saw Lennox at HD or Lowe's (don't remember). I think DeWalt makes them too. They'll drill dozens of holes and I think they're under $10 each for the 1" size. I'd suggest the 2" deep ones, you never know when you'll want a hole in a wood 2x4. I think they come in 1/16" increments.My smallest is 5/8".If you find them for a buck or two, they're for wood and won't last through one steel hole.9-11-2001......We Will Never ForgetRetired desk jockey. Hobby weldor with a little training. Craftsman O/A---Flat, Vert, Ovhd, Horz. Miller Syncrowave 250
Reply:10 seconds is unrealistic, but a magdrill for sure.
Reply:How about making a small plate for a guide and cutting the holes with plasma?I do it all the time.  My template has to be 1/4 inch larger than the size I want.Then it takes just a few seconds to cut the hole.The best things in life all come on a stick!
Reply:Originally Posted by 808APP10 seconds is unrealistic, but a magdrill for sure.
Reply:Make a friend with someone who owns a Bridgeport. T.J.www.tjsperformance.comDynasty 300 DXHTP 240HTP Microcut 380Hyperthem 85JD2 Hyd Bender and HF Hyd Ring Roller all in one =(Frankenbender)Bpt. Mill/DRO4' x 8' CNC Plasma TableInstagram: tjsperformanceYT: TJS Welding and Fabrication
Reply:Spend the $50 on a ChiCom bench top drill press, (I got mine at TSC), and get a hole saw and cutting oil.  I cut a one inch hole in 2 pieces of half-inch plate that I tacked together.  I had to stop every now and then to clean out the kerf, you'll know when it's time.  Go slow and keep it cool.  Also, make sure the OD of the pipe is really 1 inch and not one and a sixteenth.  I had to use the die grinder to make the hole the right size to slip the pipe through on mine.Be the river, Baby!
Reply:Also, make sure the OD of the pipe is really 1 inch and not one and a sixteenth.
Reply:Originally Posted by SandyThere ya go. Key point right there. A 1" rotabroach or 1" twist drill or 1" step drill is going to make a 1" hole. A 1" hole saw should cut about a 1&1/8th" plus or minus. I don't think twist drill is the way to go, even drilling up in small increments. Not with a hand drill motor anyway. When a 1" bit bites it bites big.
Reply:Originally Posted by Hammack_WeldingGet yourself a few GOOD holesaws.  Use plenty of  coolant and you will be fine.
Reply:Hmm, a lot to consider here.  I really don't see myself renting a mag drill, although I could easily purchase a cheap drill press.  As far as bits it seems my options are really hole saw or rotabroach as I don't see myself using a step bit.  The hole saw seems easier, while the rotabroach seems more accurate.  Is it a bad idea to use these with a hand drill?  I may still bring it to a shop as there are many in Brooklyn, where I live, and I only need two holes this size.  Still, there's something satisfying about doing it yourself...
Reply:Step drill about $34.00Hole saw could be risky hand held. If it grabs it could get you hurt.Otherwise regular drill bits in steps.Take it to a steel working shop and they will punch the hole with a Piranha iron worker.In manufacturing drilling a hole is very expensive, thats why holes are punched.
Reply:1 inch pipe has an od of 1-3/8" do you need a through hole, or are you going to be tapping it?  if you're tapping it, does it need to be for a taper thread or a straight pipe thread?, straight pipe threads are rare, so i would assume its a taper, if so you're going to need a reamer a a bit that's sized right, i'm too lazy to look that up right now.anyway, any sized drill bit available you will find here www.mscdirect.com
Reply:I'm having trouble with some of the terminology, but I think you're correct.  I just want to screw the strip of metal onto the thread of the pipe, which is standard plumbing pipe from home depot.  I'll probably use a large nut (if I can find a 1" nut) on top, so the hole just has to be large enough to fit over the pipe where it is threaded, but not so large it falls down.  Does that make sense?
Reply:I'll probably use a large nut (if I can find a 1" nut) on top, so the hole just has to be large enough to fit over the pipe where it is threaded, but not so large it falls down. Does that make sense?
Reply:Originally Posted by sprint7I do not think it is unrealistic with a magdrill and a rotobroach cutter.  I will cut a few 1" holes tomorrow and see how long it takes.
Reply:If that's what you are shooting for then why not just weld some one inch pipe couplings to the plate and screw the pipe into it?  If you are wanting to just screw the pipe to the plate I wouldn't worry about drilling holesI'm a Lover, Fighter, Wild horse Rider, and a pretty good welding man......I can't help wonder what  egg-"zach"-ly  you are building.  There may be an easier way.I'd rather weld than drill holes any day.
Reply:Originally Posted by Hammack_WeldingGet yourself a few GOOD holesaws.  Use plenty of  coolant and you will be fine.
Reply:blow a hole through it with a torch and weld a pipe coupler in.
Reply:A decent bi-metal hole saw in an electric hand drill can handle it with no problem.
Reply:Check        www.practool.comLast edited by R W; 06-01-2008 at 11:45 PM.