Concentric knockouts

[genesparky]

Is it required to use the concentric knockouts on a panel? What I want to know is can I pull my own knock out next to a provided knockout?

 

[infinity]

Yes, you can punch your own KO's if you prefer.

 

[genesparky]

Thanks for the reply

 

[Oakey]

Use a KO punch though..If you use a hole saw it'll be the last time you'll be able to use it.

 

[iwire]

Use a KO punch though..If you use a hole saw it'll be the last time you'll be able to use it.

You got to get some better hole saws.

 

[electricman2]

Use a KO punch though..If you use a hole saw it'll be the last time you'll be able to use it.

I'm with you here pal. Of course I might just be too cheap to buy the good ones.

 

[hockeyoligist2]

I'm with you here pal. Of course I might just be too cheap to buy the good ones.

Even the good ones will get busted (I've got Starrett!!!) if you are overlapping the concentrics. They will pop loose and Bye Bye hole saw teeth!

 

[iwire]

Of course I might just be too cheap to buy the good ones.

I am too but I don't buy them, I just order them.

That said, drilling metal enclosures is almost all I ever use hole saws for.

What are you guys using hole saws for?

I also use uni-bits, manual punches, hydraulic punches and even have access to a 'C' punch tool that lets you punch KOs without predrilling a hole.

IMO the fastest and less likely to kill a cordless battery is a hole saw in smaller sizes. The downside is a 'messy' holes.

 

[paul]

I tried to punch a 3" conduit hole into a QO loadcenter. It didn't work, regardless of where the concentrics were located in relation to the punch. Maybe next time I should use a hole-saw.

 

[iwire]

Even the good ones will get busted (I've got Starrett!!!) if you are overlapping the concentric.

Yeah you got me there, I certainly can't argue with that.

I admit if I have to overlap concentrics my first choice is a hydraulic punch set.

 

[triphase]

Yep!...Greenlee hydraulic Knock Out Kit....got one on My truck.....hole saws are too centrifigal and will blow out concentrics and eccentrics.....

 

[don_resqcapt19]

We use these for 1" and smaller conduit. The hole is almost as good as a KO. I won't use standard hole saws for conduit openings.
Don

 

[LarryFine]

I've been using the same Greenlee hole-saw set, 1/2" thru 2", and have drilled galvanized cellular-platform steel, panel ands with and without KO's, painted CT cabinets, just about everything, and after more than three years, there is not a single tooth broken on any saw cup.

The only "secrets" I use are slow speed (using my 24-volt DeWalt almost excusively), light pressure, and cutting oil. I have had to wedge in the occasional KO segment back in place under a locknut. I will admit that I have bent or broken a couple of pilot bits, however.

 

[peter]

Don,
You are very right. Holecutters are the cat's meow. Hougens is another manufacter or perheps the manufacturer of these.
I tend to drill a small hole at the center point with a self-drilling sheet metal screw [Tek screw]. These are cheap and quite replacable and seem to speed things up. And the cut out discs can be used as fender washers!
~Peter