Nees help - Non flame cut hole in 2.5" plate

[dstig1]

Flame may be out...but is plasma? Much easier to get a cleaner cut, especially with a circle guide.

[crazyal]

If you do go with a hole saw I find what works well for me is to drill the pilot hole first and then use a solid rod, not a drill bit in the hole saw arbor.

[ghenges]

Unfortunately my mag drills will only work up to 1.5" annular cutters. I was hoping someone would be familiar with line boaring for pins on heavy equipment. It also has to be portable as I do this in others shops.

Perhaps you might use your small Hougen mag drill to hog out a hole similar to what this guy did:




Or use a diamond core drill to do the job.
Several years ago I needed to drill fairly accurate 4 inch holes in 3 inch thick plate.
It was rather slow, it took about 45 minutes per hole because you can't crowd a diamond bit drilling steel like you can in concrete..

[lostcause]

Flame may be out...but is plasma? Much easier to get a cleaner cut, especially with a circle guide.

plasma cuts are considered the same as flame cut for structural steel applications

[dstig1]

Ah well. I tried... You said there was a limit on that - but what is the limit? If you need a 2.5" hole and can plasma a 2.4" hole, and grind it out to fit, it might be worth it. Obviously the OP said doing too much of this made it not worth it, but how much is too much???

[Mark @ Everlast]

Water jets are faily common these days, and am surprised, and have some work done that I do during fabrication subbed out to a local machine shop with one and I live in the sticks. Makes a big difference. 2.5 inches in NO problem. A HD plasma system could possibly do it, though yes, it is flame cut, it is highly accurate.

[Inkomodius]

Your living in the sticks and my living in the sticks are two different things LOL. My closest IKEA Is 500km away hahaha... Ikea is a measuring system now. I don't get to choose who does the cutting. I contract to the company that bids the work, orders steel and then give me steel and prints and says go. So I want to keep my costs down, and make my life easier. So far I am going to try a boring bar on a mag press and see how that works. That diamond core bit looks promising as well. Are they high speed? I am not familiar with them im assuming they are available in various arbors?

As far as plasma goes, its the same as a torch. Granted more accurate but still a flame, even a LASER is considered flame cut to an engineer.

[mjncad]

...even a LASER is considered flame cut to an engineer.

Now that's an anal engineer considering how fine the laser beam is that does the cutting.

[ericher69]

Now that's an anal engineer considering how fine the laser beam is that does the cutting.

Doesn't have anything to do with accuracy but the changes at a molecular level that the flame/plasma/laser produces in steel.

[lostcause]

here's a question for the original poster -

how accurately can you get a flame cut hole in the piece? from what you said i assume that you have to put the hole in after the two 1" plates are welded to the web of the w12x87, correct? this makes the flame cutting operation more difficult than if you were cutting the holes in each piece then weldign them together. it also sounds like you are in a fairly remote area, and i don't know what is available for services, but would this be any easier to do, and can you get modifications approved:

flame cut a larger hole (+/-5") and weld in a sleeve where the pin goes. assuming you can source suitable round stock i would think it might be easier to find a local that has the capability to chuck up and drill/bore a 3" hole through short lengths of round stock. you could then weld these in to the flame cut hole you created. this isn't extremely easy or cheap, but trying to use a boring head on a mag drill to do these repeatedly sounds pretty tedious and also not cheap. i also have no clue how your approval process works, such as whether you can even get changes like this approved, or how long the approval process takes, and whether that blows your schedule out the window.