Tips needed for drilling through hardened steel?

[pet73]

To add one more thing: it is not a steel plate but a 5mm thick coin shaped disc. The object I want to remove is a metal mount screwed onto a wall, and to protect direct access to the screws these discs are fixed / inserted in the metal plate just on top of these screws (plate has holes in it for this purpose and the discs were hammered in these in the past). So I am hoping to make a hole in these discs so that I can then remove them and access the screws.

 

[Jasonb]

If thats the case then why not stitch drill around the caps and prize them out, thats assuming you don't want the plate.

Or have someone weld a nut to the disc and use a slide hammer to drift them out.

Jason

 

[Trazor]

If it really is hardened steel, it will be brittle.
Get a heavy ball pein hammer and hammer it, use the ball end, it may well shatter.
If it does shatter, pieces WILL fly out at speed....WEAR PROTECTIVE GLASSES.

 

[pet73]

Drilling around the discs is not any easier, as the plate in which they sit is also from hardened steel.

I can see the tip on welding something onto the disc and then pulling out can work, but I don't have any welding experience/equipment.

 

[Trazor]

I can see the tip on welding something onto the disc and then pulling out can work, but I don't have any welding experience/equipment.

If the disc is hardened then any welds will be brittle, and they will snap off with any force.

If you are getting to the point of bringing equipment in, get a set of gas bottles, heat the plate up to anneal it, and immediately drill it whilst hot.

 

[r896neo]

do you know the exact arrangement of screws and the shape of the fixing plate etc, it may be easier to drill the wall and pull this thing out plugs and all and then patch up the plaster.

 

[Trazor]

Pictures may help in this instance.

 

[Jasonb]

You could take a die grinder to the cover disks, that will cut it weather hardened or not.

Do you know if its just case hardened or is it a high carbon steel thats been hardened & tempered.

Jason

 

[JohnD]

is it a wallsafe? if not, what?

 

[Bodgeit and scarper ltd]

if it was me doing it i would use my Oxy/Acetylene gear or my disc cutters. as you don't have much in the way of tools the best thing to do is knock the wall down

 

[wotan]

if it was me doing it i would use my Oxy/Acetylene gear or my disc cutters. as you don't have much in the way of tools the best thing to do is knock the wall down

I think with his apparent lack of experience, (and tools) at best if he tried to use an angle grinder or oxy/Acetylene, he would burn the place down.
With careful measurement he could attack it from the other side of the wall
providing neighbours would grant acess.

 

[john2485]

Hi I would suggest that you buy a single Tungsten carbide bit, for test purposes, say 5mm at the most, this will cost around a tenner if my memory serves me correct so not cheap! if this does not penetrate it then you have no chance of drilling it in situe! unless you can get it hot and I mean hoooooot with out the fire brigade coming out!!!

what coulor finish as the metal got? is it painted? is it possible to scratch any finish of the surface to show the metal in its original form?

 

[JohnD]

With careful measurement he could attack it from the other side of the wall
providing neighbours would grant access.

The fixing bolts can probably be undone from inside the wall-safe (if that's what it is - he won't say)

this might need to be done while the bank is closed

 

[r896neo]

The speculation is enjoyable but if he is a bank robber it'll be a long and fruitless career by the sounds of it so far!

 

[wotan]

John2485 wrote:
what coulor finish as the metal got? is it painted? is it possible to scratch any finish of the surface to show the metal in its original form?

Olive green, with the words CHUBB embossed on it.