Biker,
Yes and no. Will it pierce 3/4" plate? Yes. Will it do it every time? No. It "will" pierce 1", but it can get ugly. There is molten stuff flying EVERYWHERE and the thicker the material is, the higher the rate that it misses and doesn't pierce. As the crater gets deeper, the angle of the ejected molten material gets steeper, and climbs closer to 180 degrees, which it basically straight back into the torch and nozzle / shield. When it fails, it has completely scrapped the nozzle and shield, sometimes the ohmic retaining cap as well. So, to top off the $40 of consumables that are scrap, it leaves a nice big fat crater full of junk. Guess what. No more metal to transfer an arc to, or at least not close enough for it to transfer to. So that piece of steel isn't going to be what you were making now either. If it was something with say, 10 holes and a perimeter cut, and it junks the next to last pierce, lots of $ and frustration. Hard on the profit margin, especially with thick plate. A 24" x 24" piece of 1 1/4" weighs like 225# if I remember correctly, or close, and if I get the good guy hook up on a drop that is laying around, I still pay $110 or so for it. Plus I gotta go get it.
I have the map of the road you are thinking about taking, got two shirts and came back. TRUST ME ON THIS, if you are going to be doing much thick stuff, get a mag drill. Cheap ones are in the $750-$800 range, and the cutters start around $60 for the good ones. I don't use the cobalt tipped ones, only use good carbide cutters. I have cut 1000's of holes with my original 7/16" cutter, as long as you keep the coolant flowing, it doesn't get hot, so long as you are cutting mild steel it will take a LONG time to dull. The other nice thing about the carbide cutters is that you can have them sharpened for around $15, long as you haven't broken any teeth. As far as the drill, I bought a Nitto Kohki, comes with some nice features like soft start, two speed, and auto torque indicator, as well as a safety shutdown if it gets in a bind and the bits get stuck. Basically can't make it tear itself up. None of them work for shit on plate thinner than 1/2". but you don't need one on thin plate now do you?
You can broach thinner plate if you put a thicker piece under if for the magnet, or say, like I do, throw it up on the welding table with the 1/2" plate table top for backup. Let it hang off the edge just a little and away we go.The drill clamps with something like 4000 lbs of force or some stupid high number. I was surprised at the money I have been able to make with the drill. I charge for broaching holes in thick plate, and people are willing to pay. It seems like a lot to pay for one hole in something, but when you need a hole and have no way to do it correctly, it's a bargain and people never even flinch. I have also been marking, cutting and drilling layout tables for welders. Mark all the holes, cut the perimeter to their size, then drill it all out. 5/8" and 3/4 plate make nice layout tables, and while it's repetitive and tedious, it sure pays good. Generates a lot of traffic for the shop as well. I know it seems like a lot of $ up front, but I have to say it was a great addition to my shop and I would do it again.
I know it's a long winded answer to your question, but hopefully it will save you the same frustrations I had. Hardest lessons learned are the ones best remembered. Or so I have been told
Shane
I use the 7/16' cutter, as it is the smallest, and hence the cheapest cutter. It will cut a 7/16" hole in 1" plate in under 30 seconds. The coolant is not flammable, and has corrosion inhibitor in it so it doesn't rust the parts. I think the gallons of concentrate mix makes 50 gallons of diluted coolant. If you have any more questions or need help getting it done let me know I or someone else I am sure can help.
