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Age Quod Agis |
Do I go for the gusto with a 3/4 bit, or do I drill a 1/4 pilot and then finish it out? I have a drill press, but not a full machine shop. "I vowed to myself to fight against evil more completely and more wholeheartedly than I ever did before. . . . That’s the only way to pay back part of that vast debt, to live up to and try to fulfill that tremendous obligation." Alfred Hornik, Sunday, December 2, 1945 to his family, on his continuing duty to others for surviving WW II. | ||
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| 7.62mm Crusader |
I would step it up from a pilot. Block and clamp the work piece for safety. 3/4" Drill can spin that piece of stock in a very dangerous way. Block your work piece. If you got a center punch, that will locate your pilot hole better. | |||
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| Eating elephants one bite at a time  |
As mentioned, block and clamp. Don't be afraid to use multiple bit sizes between 1/4 and 3/4. Lubrication is also a good idea. Let the bits do the work. | |||
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| Age Quod Agis |
Thanks. I have a center punch, plenty of HSS drill bits, and cutting fluid. I had planned to clamp the stock to the drill press table for safety. I have drilled steel before, just haven't tried a hole this big before. I need to build a bracket for a bush hog, and 3/4 is the bolt size. I appreciate the help. "I vowed to myself to fight against evil more completely and more wholeheartedly than I ever did before. . . . That’s the only way to pay back part of that vast debt, to live up to and try to fulfill that tremendous obligation." Alfred Hornik, Sunday, December 2, 1945 to his family, on his continuing duty to others for surviving WW II. | |||
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| Member |
____________________________ "Fear is a Reaction - Courage is a Decision.” - Winston Spencer Churchill NRA Life Member - Adorable Deplorable Garbage | |||
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| Member |
Use a step bit. The cheap ones like these don't last really long (10 holes or so) https://www.amazon.com/Vastar-...-Steel/dp/B073JM4D8F or you can buy really nice ones in the $40-$50 range. | |||
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| Member |
____________________________ "Fear is a Reaction - Courage is a Decision.” - Winston Spencer Churchill NRA Life Member - Adorable Deplorable Garbage | |||
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| His diet consists of black coffee, and sarcasm.  |
If you want to drill any hole much bigger than 3/8", start small and progressively increase the size. For a 3/4" hole you'll want ~3 steps. | |||
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| Too old to run, too mean to quit! |
Given his apparent willingness to spend money, why does he not just take it to a machine shop and pay them to do it? Faster, easier, safer, and probably cheaper. Several years ago I was making a mounting plate for my router table. 1/4 inch thick stock. Thought about all the work, problems, etc etc. Took it to a local machine shop where they did the work while I waited, cost me 10 bucks. Elk There has never been an occasion where a people gave up their weapons in the interest of peace that didn't end in their massacre. (Louis L'Amour) "To compel a man to furnish contributions of money for the propagation of opinions which he disbelieves and abhors, is sinful and tyrannical. " -Thomas Jefferson "America is great because she is good. If America ceases to be good, America will cease to be great." Alexis de Tocqueville FBHO!!! The Idaho Elk Hunter | |||
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Drill Here, Drill Now |
If the hole doesn’t have to be pretty I’d use a plasma torch. Faster, safer, cheaper (in terms of consumables). Ego is the anesthesia that deadens the pain of stupidity DISCLAIMER: These are the author's own personal views and do not represent the views of the author's employer. | |||
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| Age Quod Agis |
Hmmm, there is a machine shop about 5 miles away. I might take it there. "I vowed to myself to fight against evil more completely and more wholeheartedly than I ever did before. . . . That’s the only way to pay back part of that vast debt, to live up to and try to fulfill that tremendous obligation." Alfred Hornik, Sunday, December 2, 1945 to his family, on his continuing duty to others for surviving WW II. | |||
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A Grateful American |
Machine shop or step bit. Progressive drilling with several bits multiplies the number of times you can have a bit hang and if your hand drilling, you are playing "Mechanic Roulette", not a matter of "it", but "when" and how much blood... I can do all my own work (given the correct tools), but some things are better ROI. This would be one of those. I was doing oiling mods on an engine block, one was to enlarge an oil passage from 1/2" to 5/8" x 11" depth along the side in high nickel cast iron with wall thickness of only a few millimeters in some places. Trying to drill that far by hand and ensure it was true, was more than I wanted to try at home, so I paid my machinist $50 to drill it. Cost of a bit and the effort, I came out way ahead. "the meaning of life, is to give life meaning" ✡ Ani Yehudi אני יהודי Le'olam lo shuv לעולם לא שוב! | |||
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Member |
With a drill press I would use a hole saw Hell has no fury like a liberal confronted with reality | |||
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| Partial dichotomy |
Go up in steps, use plenty of oil and set your drill speed slow. You won't have any problems. SIGforum: For all your needs! Imagine our influence if every gun owner in America was an NRA member! Click the box>>>  | |||
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| Member |
Another option would be to use a Hole Saw. I've cut 3 inch holes for hydraulic pressure gages in 3/8 inch steel using a hole saw and hand drill and it's not that difficult. The key is to slightly wobble the drill so the hole is actually cut to a diameter a touch larger that the diameter of the saw. Fail to do this and about 1/4 inch into the cut you'll find the saw starting to bind as the steel heats up. BTW, once tried to enlarge the tapped hole for a locking screw on the ram shaft of a 75 ton hydraulic press by stepping up from a 3/8 hole and darned near broke my wrist when the bit jammed. BTW, hand drill was a 1/2" Milwaukee Magnum Hole Shooter and this drill is capable of producing a lot more torque than one would expect. Should have added the second hand grip to the drill but I was "in a hurry". Point is don't try "stepping" with a hand drill because you will be dealing with constant jams and even with a low power 3/8" hand drill those jams can add up to some pain in the wrist and a LOT of broken drill bits. I've stopped counting. | |||
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Tinker Sailor Soldier Pie |
Always step up to a size that big, unless you're using a hole saw. ~Alan Acta Non Verba NRA Life Member (Patron) God, Family, Guns, Country Men will fight and die to protect women... because women protect everything else. ~Andrew Klavan | |||
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| Member |
What DEC505 said. 3/4" bi-metal hole saw will cut just over size and should work well for a 3/4" thru bolt. Clamp well. | |||
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Member |
Clamp it down well, use oil, pilot drill it - run 250-300rpm with the 3/4 bit. -Scott -NRA Pistol Instructor -NRA Shotgun Instructor -NRA Range Safety Officer -NRA Metallic cartridge & Shotgun Reloading Instructor -MA Certified Firearms Instructor | |||
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| Three Generations of Service  |
Ding-ding-ding! As long as the hole doesn't have to be dead accurate, hole saws are my go-to for anything over 1/2"   I built a scissors hoist for my dump trailer from scratch (using purchased plans) and all the holes were done with various sizes of hole saws. Be careful when following the masses. Sometimes the M is silent. | |||
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| Avoiding slam fires  |
I always use step up sizes to get to that size. Saves drills and is safer than hole saws IMHO More accurate also. | |||
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