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breaker panel: the best way to knockout only the -desired- knockouts?

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dave

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Sep 27, 2008, 7:27:48 PM9/27/08
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I need to knockout a pre-punched hole in the bottom of my breaker panel.
the hole size will be fairly large, but not quite as big as the outer ring.

I'm kind of wondering how to "knock out" JUST the rings I -want- knocked
out, withOUT knocking out any 'undesired' outer knockouts in the same
circle...

please see this image and tell me if I have it right...

http://www.image-upload.net/files/5385/knockouts_how-to.jpg

thanks

toolie

John Grabowski

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Sep 27, 2008, 7:51:39 PM9/27/08
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"dave" <tool...@weirdstuffcox.net> wrote in message
news:SjzDk.13163$VS3....@newsfe12.iad...


Even professionals sometimes have problems getting just the ones they want
out. Thank goodness for reducing donuts. You have it right as to where to
start, but don't expect or even try to get the knockout removed just by
hitting with a hammer and screwdriver. Usually you would start with the
smaller center KO first, but in this case the next size may be easier from
inside. If you look carefully at the way the knockouts are stamped you will
see that they alternate between getting punched in and getting punched
outwards. The center KO is stamped to be punched inward which makes it a
little more difficult if you can only work from the inside. Once you get it
started by hitting with the screwdriver you need to twist it. Knock it
forth and back a few times to loosen it up. If you have a good pair of
diagonal pliers or BX cutters you can sometimes get in there and cut one or
more of those welds. Just don't try to get it real fast. Be patient and
work it out. You will feel the knockouts get looser as you move them forth
and back. It will be a little more difficult since the panel appears
recessed in a wall. If you have a long thin screwdriver you can stick it
between the edge of the wall and the edge of the panel to apply a little
pressure from the outside.

RBM

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Sep 27, 2008, 8:09:13 PM9/27/08
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"dave" <tool...@weirdstuffcox.net> wrote in message
news:SjzDk.13163$VS3....@newsfe12.iad...

The correct answer: CAREFULLY, and half the time you muck it up anyway. If
the ko is protruding into the panel, like the center one, you have to punch
it inward. The next ring is going outward and must be punched out in the
same direction. Once the center ko is out, you may be able to pick at the
others to get them out. Do be sure to have some KO washers handy just in
case.


metspitzer

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Sep 27, 2008, 8:13:24 PM9/27/08
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I googled "removing concentric knockouts" and really didn't find
anything

What I do is pop out the center, which is pretty easy. I then take
the second size and fold it completely in half, so I can grip it with
lineman pliers, and gently work it back and forth until it pops.

Pete C.

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Sep 27, 2008, 8:43:41 PM9/27/08
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Start by removing the center one-pice KO.

For each subsequent ring, use your pliers to carefully pry up the ring
halves until they are up enough to cut each one in half with diagonal
cutters leaving the two anchor points with a wing on each side. Now use
the pliers to squeeze the wings together and then rock back and forth
parallel to the anchor point until it breaks off. If you try to rock in
the other direction it will tend to twist the next ring up.

A bit difficult to describe, but it should make sense when you're doing
it.

jack

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Sep 27, 2008, 11:23:40 PM9/27/08
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> The correct answer: CAREFULLY, and half the time you muck it up anyway.

I'm glad everyone has problem; I thought it was just me. Why don't they
improve the design? It can't be that hard.


Pete C.

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Sep 28, 2008, 5:05:19 AM9/28/08
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They did improve the design, they make panels without any knockouts so
you can punch them as needed exactly where you want them and in the size
you want. You of course need the punch set and a drill for the pilot
hole.

Blattus Slafaly

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Sep 28, 2008, 9:33:00 AM9/28/08
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Just hit the most inside plug where it is not connected with a tab until
it pops out, then use long nose pliers to work it back and forth until
the tabs snap. Just be attentive. If you take out too much you can
always get the reducing rings. Another option is find another plug the
right size and use that.

--
Blattus Slafaly ? 3 :) 7/8

John Grabowski

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Sep 28, 2008, 10:51:35 AM9/28/08
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"jack" <ja...@yahoo.org> wrote in message
news:5NCDk.87$qg...@fe101.usenetserver.com...

>> The correct answer: CAREFULLY, and half the time you muck it up anyway.
>
> I'm glad everyone has problem; I thought it was just me. Why don't they
> improve the design? It can't be that hard.


Occasionally I come across a pull box or something else that has very easily
removed KO's. Unfortunately the concentric's sometimes break off after I've
installed a connector. Then I need to use some donuts to fill the hole.
With the more difficult ones you have a good chance of keeping the
concentric's in place if you do it carefully.

Uncle Monster

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Sep 30, 2008, 12:52:11 AM9/30/08
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I use a 1/8" bit to drill out the
little hinge tab that you have marked
as #2. Drilling out those little tabs
makes it much easier to remove the rings.
In commercial/industrial work where I
usually have access to both sides of the
box I use a knockout punch turned backwards
to press the rings back in when they break
loose. If you only want to remove the center
KO, you can drill through the center with
a small bit then use an awl to pop it out.

[8~{} Uncle Monster

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