Putting a 3'' Hole through 1.5'' Thick Iron in a Punch Press
Putting a 3'' Hole through 1.5'' Thick Iron in a Punch Press
(OP)
Does anyone have any creative ideas for putting a 3'' round or square hole through a 1.5'' thick cast iron in a punch press? The hole doesn't need to be clean or any specific size, it just needs to be large enough for a stamping to drop through it. My fallback was to chain drill it, but that is time consuming and there is not enough clearance for the drill up top, so I would have to drill it from underneath. I was thinking I would start with a pattern to start the holes and then just chain drill it with 1/4'' holes.






RE: Putting a 3'' Hole through 1.5'' Thick Iron in a Punch Press
Can you use a 3" bi-metal hole saw and maybe drill from each side? They are really fast for cutting and I've used them for 1" plate.
Dik
RE: Putting a 3'' Hole through 1.5'' Thick Iron in a Punch Press
RE: Putting a 3'' Hole through 1.5'' Thick Iron in a Punch Press
Mike Halloran
Pembroke Pines, FL, USA
RE: Putting a 3'' Hole through 1.5'' Thick Iron in a Punch Press
Beware, you're also weakening the frame when you do that.
You can get core drills that will cut a plug, but I don't know if they're practical for your situation. Seems like the ones I've seen were shallower.
RE: Putting a 3'' Hole through 1.5'' Thick Iron in a Punch Press
A diamond core drill will do the three-inch diameter hole. Use a concrete coring bit. You might dull the bit enough that it will be useless thereafter, so get ready for the cost of a new 3" diamond bit...about $250 US.
RE: Putting a 3'' Hole through 1.5'' Thick Iron in a Punch Press
Dik
RE: Putting a 3'' Hole through 1.5'' Thick Iron in a Punch Press
What you are doing seems like it would be a real pain with a blade.
Maybe drill four holes and connect them with a blade./
RE: Putting a 3'' Hole through 1.5'' Thick Iron in a Punch Press
RE: Putting a 3'' Hole through 1.5'' Thick Iron in a Punch Press
Dik