I need to remove 100 feet of 1/4" flat plate that is attached to my
shop floor. Every foot the plate is attached to the floor with 1/2"
rebar that is welded in the center of the plate. When the shop floor
was poured, the pieces of rebar were concreted in and stuck 1/2" above
the slab. Then the 1/4" plate was drilled every foot for the rebar,
laid down flat on the slab, and welded. To remove it I've considered
using a 7" grinder(very slow), trying to use a torch at an
angle(difficult since the plate is solid against the concrete) and
using a gouging electrode and a prybar. Any and all might work, but
I'm sure open to some better ideas.

I would try hitting the top of the weld with your angle grinder to get
a flat spot. Center punch what you think is the middle, and drill with
1/2 inch or 5/8 inch drill to eliminate weld. If you get the concrete
hot with the torch it will pop off bits of cement at you.

Dan



tomd wrote:
I need to remove 100 feet of 1/4" flat plate that is attached to my
shop floor. Every foot the plate is attached to the floor with 1/2"
rebar that is welded in the center of the plate. When the shop floor
was poured, the pieces of rebar were concreted in and stuck 1/2"
above
the slab. Then the 1/4" plate was drilled every foot for the rebar,
laid down flat on the slab, and welded. To remove it I've considered
using a 7" grinder(very slow), trying to use a torch at an
angle(difficult since the plate is solid against the concrete) and
using a gouging electrode and a prybar. Any and all might work, but
I'm sure open to some better ideas.

I need to remove 100 feet of 1/4" flat plate that is attached to my
shop floor. Every foot the plate is attached to the floor with 1/2"
rebar that is welded in the center of the plate. When the shop floor
was poured, the pieces of rebar were concreted in and stuck 1/2" above
the slab. Then the 1/4" plate was drilled every foot for the rebar,
laid down flat on the slab, and welded. To remove it I've considered
using a 7" grinder(very slow), trying to use a torch at an
angle(difficult since the plate is solid against the concrete) and
using a gouging electrode and a prybar. Any and all might work, but
I'm sure open to some better ideas.

Do you have a goiod two-hand drill or can you rent one? If so, maybe use a
hole saw to cut around the rebar? How about a good centerpunch or drill a
1/4" hole and then a 3/8" hole or even larger to guarantee you get the whole
thing... You'd probably dull a bunch of bits everytime you hit the
concrete, but if you went out and bought a bunch of cheap bits, it wouldn't
be too expensive to do. And probably faster than the grinder for sure!
Plus, a torch will ruin the concrete. The moisture inside the concrete
expands and makes pieces "mushroom" off at odd angles - sometimes quite
rapidly.

Regards,
Joe Agro, Jr.
http://www.autodrill.com
http://www.multi-drill.com

V8013

Know someone with a motorcycle in the NY Metro area?
http://host.mynocdns.com/mailman/lis...rides_yunx.com

Several things come to mind. My first idea is to use a carbide tipped hole
saw in a mag drill and cut through the plate around the rebar and weld area.
I suggest the mag drill as you can control the depth so you are not trying
to punch through the concrete. You might be able to hold just a little shy
of all the way.

Another thing to think about is why the steel plate is there in the first
place. From your description this sounds like the 1/4" plate might very
well be a structural component of your building and removing this may cause
a world of grief. If a smooth floor is your goal, you might wish to
consider a self leveling compound to top everything off and leave the plate
in place. I strongly urge you to consult with a structural engineer before
you remove the plate.

--

Roger Shoaf

About the time I had mastered getting the toothpaste back in the tube, then
they come up with this striped stuff.


"tomd" wrote in message
oups.com...
I need to remove 100 feet of 1/4" flat plate that is attached to my
shop floor. Every foot the plate is attached to the floor with 1/2"
rebar that is welded in the center of the plate. When the shop floor
was poured, the pieces of rebar were concreted in and stuck 1/2" above
the slab. Then the 1/4" plate was drilled every foot for the rebar,
laid down flat on the slab, and welded. To remove it I've considered
using a 7" grinder(very slow), trying to use a torch at an
angle(difficult since the plate is solid against the concrete) and
using a gouging electrode and a prybar. Any and all might work, but
I'm sure open to some better ideas.

On 2005-02-25, tomd wrote:
, trying to use a torch at an angle

If you torch it you'll spall the concrete.

--
Ben Jackson

http://www.ben.com/

tomd wrote:

I need to remove 100 feet of 1/4" flat plate that is attached to my
shop floor. Every foot the plate is attached to the floor with 1/2"
rebar that is welded in the center of the plate. When the shop floor
was poured, the pieces of rebar were concreted in and stuck 1/2" above
the slab. Then the 1/4" plate was drilled every foot for the rebar,
laid down flat on the slab, and welded. To remove it I've considered
using a 7" grinder(very slow), trying to use a torch at an
angle(difficult since the plate is solid against the concrete) and
using a gouging electrode and a prybar. Any and all might work, but
I'm sure open to some better ideas.

Rent or own a magnetic base Drill - core drill around the rebar - e.g. 1" holes.
Then lift off the plate and cut circles off as wanted - torch or real metal work -
a good sledge and cold chisel.

Martin

--
Martin Eastburn, Barbara Eastburn
@ home at Lion's Lair with our computer
NRA LOH, NRA Life
NRA Second Amendment Task Force Charter Founder

I would pull up one or two plates by whatever laborious means are
available--even grinding, so you can get a look at the concrete. Since the
floor was poured with the expectation that it would be covered with steel,
it may not be well finished. If it's going to require a topcoat to make it
usable, there may not be much downside to using a torch on the steel anchor
points. It would be a big waste to take up the steel very carefully, only
to find that you don't have a good surface under there anyway.

Remember, also, that you are going to have to deal with all those re-bar
stubs. It may turn out that the easiest way is to cover them with an inch
or so of new concrete.

Man, that's going to be a LOT of work, no matter how you do it. WHY do
you want it removed? It could be an advantage having it there. For
instance, you could use it as a giant welding table. You could tack
weld pieces in place to hold them. You could weld machinery anchors to
it. You could weld jigs to it for large frame-ups or bending patterns.
A lot easier to do and change than drilled anchors in concrete. Think
about it. Bob

The previous owner of my shop cut a 4 foot wide trench, 50 feet long
and installed a trampoline runway. I'm planning on filling it in with
concrete and would like to remove the steel to allow a normal floor. I
have one real garage door to drive into, but the trampoline pit goes
the length of the shop and is just infront of the door. Right now I
cannot even drive a car into the shop.

I like the idea of a magnetic base drill, but if used a core drill then
I still have the grinding issue of the rebar what is left of the plate.
I'm may look into renting such a drill, and then just drilling out the
rebar using several steps of bits. .

How about cutting the concrete again, jack hammering the mess out,
and pouring the whole thing back? No drilling, no burning, no
grinding, no spalls, good clean floor patch.

(top posted for your convenience)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Keep the whole world singing . . . .
DanG (remove the sevens)




"tomd" wrote in message
oups.com...
The previous owner of my shop cut a 4 foot wide trench, 50 feet
long
and installed a trampoline runway. I'm planning on filling it
in with
concrete and would like to remove the steel to allow a normal
floor. I
have one real garage door to drive into, but the trampoline pit
goes
the length of the shop and is just infront of the door. Right
now I
cannot even drive a car into the shop.

I like the idea of a magnetic base drill, but if used a core
drill then
I still have the grinding issue of the rebar what is left of the
plate.
I'm may look into renting such a drill, and then just drilling
out the
rebar using several steps of bits. .

On 1 Mar 2005 06:19:22 -0800, "tomd"
vaguely proposed a theory
.......and in reply I say!:

remove ns from my header address to reply via email

Sorry, I am way out here.

WTF is a trampoline runway?




The previous owner of my shop cut a 4 foot wide trench, 50 feet long
and installed a trampoline runway. I'm planning on filling it in with
concrete and would like to remove the steel to allow a normal floor. I
have one real garage door to drive into, but the trampoline pit goes
the length of the shop and is just infront of the door. Right now I
cannot even drive a car into the shop.

I like the idea of a magnetic base drill, but if used a core drill then
I still have the grinding issue of the rebar what is left of the plate.
I'm may look into renting such a drill, and then just drilling out the
rebar using several steps of bits. .

Wet the concrete floor down, cut with torch.

OldNick wrote:
On 1 Mar 2005 06:19:22 -0800, "tomd"
vaguely proposed a theory
......and in reply I say!:

remove ns from my header address to reply via email

Sorry, I am way out here.

WTF is a trampoline runway?




The previous owner of my shop cut a 4 foot wide trench, 50 feet long
and installed a trampoline runway. I'm planning on filling it in
with
concrete and would like to remove the steel to allow a normal floor.
I
have one real garage door to drive into, but the trampoline pit goes
the length of the shop and is just infront of the door. Right now I
cannot even drive a car into the shop.

I like the idea of a magnetic base drill, but if used a core drill
then
I still have the grinding issue of the rebar what is left of the
plate.
I'm may look into renting such a drill, and then just drilling out
the
rebar using several steps of bits. .

My building was used for a gymnastics school.
The 1/2 inch steel has holes drilled every couple of inches with
extension springs, and a canvas tarp is stretched across the pit held
on each side by the springs . The kids would bounce down the
trampoline doing flips.

On 2 Mar 2005 06:54:00 -0800, "tomd"
vaguely proposed a theory
.......and in reply I say!:

remove ns from my header address to reply via email

OK. Thanks.

I tend to agree with what a couple of others said. Leave the steel
there and use it a a hold-down for projects, either magnetic or tack
welded. Fill in the hole with dirt and lay cement to floor level.

My building was used for a gymnastics school.
The 1/2 inch steel has holes drilled every couple of inches with
extension springs, and a canvas tarp is stretched across the pit held
on each side by the springs . The kids would bounce down the
trampoline doing flips.