Tips needed for drilling through hardened steel?

[pet73]

The problem is solved in a different way.

I did try to drill through it. Using a hard-metal center point did indeed give a good dimple / pit to start drilling. However, the drilling was no succes, the material was simply too hard. In the end I tried to remove the wall bracket by means of a heavy duty crowbar, and I managed to slowly 'pull' the plugs out of the wall. This was always my plan B, although I never thought it would work. In fact I was surprised to learn how succesful this approach was. I had expected that long plugs in a concrete wall would have enormous friction and would be impossible to pull out.

Thanks everyone again for thinking with me.

 

[Trazor]

Do we get a share?

 

[wotan]

Do we get a share?

Only if he can get the darn thing open.

 

[^neo^]

phone box full of 'ebay rare' 20p coins?

 

[JohnD]

he's not going to tell us

 

[davey1000]

Hardened steel can easily be drilled using a stellite drill.

But you must be able to remove this plate from the wall, and drill it vertically in a pillar drill, lots of pressure no coolant, watch out for red hot chippings.....

Hmm disagree. I bought some stellite drills at a car boot sale. Make is Deloro and they are like a three sided pyramid. I have been trying to drill a hole in the end of a Snail Brand two and a quarter AF spanner. (handy for packing glands on stern tubes) Obviously for marine work it is nice for spanners to have a hole to take a lanyard but mine doesn't have one. Maybe the drill press needs a bigger motor as so far the results are pathetic but in all fairness the spanner is probably chrome-vanadium. I've spent well over an hour on the job but the hole is barely halfway through, possibly less and the edge soon gets taken off the stellite. Rather surprisingly a cheap and cheerful bench grinder resharpens the stellite effortlessly - doesn't even need a green grit wheel. How much power do these bits need? Are they outdated and obsolete? At this rate I'll have to try a Rotabroach.

 

[TicklyT]

Spark erosion?

http://www.metalwebnews.com/manuals/spark-erosion.pdf

 

[JohnD]

I think I heard that you can drill into safe locks using a masonry drill

the tip will be hard enough, but I presume the angle is not ideal

fancy giving it a try?

 

[Alarm]

Just seen this and it tickeled me.

A TCT drill would do this in seconds. Or a colbalt tipped one, but slower.
A masonary drill with the angles reground would too.

Only spent over 25 years in the security industry as a Losksmith, Electronic Systems engineer.

 

[maltaron]

Dewalt "EXTREME" drill. These have a starter point then work like a milling cutter for the main hole.

 

[wotan]

he's not going to tell us

I reckon it's a Honda Fireblade motocycle he's halfinched

 

[Lockman1]

RHC - Rockwell Hardness C

HSS Drill Bits - Work well up to the 50ish RHC
Drill - Mild steel, Some tool steel, Some Spring Steel
No Drill - Hard Plate, Anti Drill Plate, 404c Stainless Steel
Pro - Good in Hand Drills and most drilling applications
Con - Has limitations in hardened steels

Cobalt - Works up to 58ish RHC
Drill - Mild Steel, Some Spring Steel, Some Tool Steel
No Drill - Hard Plate, Anti Drill Plate, 440C Stainless Steel
Pro - Good for hand drills and most drilling applications
Con - Has limits with hardened steel

Carbide Tipped - Will drill almost any steel, Hard, Stainless or Mild.
Pro - Drills all steel
Con- Blunt tip requires extreme pressure to produce cuttings. Drill bit is hard to start on all steels.

Diamond Coated Drill Bit - Cuts on most steels(Not Hard Plate) just not for long.
Pro - Will Drill most steels (Not Hard Plate)
Con - Cutting stops quickly after diamond grit has warn off, Then behaves like HSS bit

Solid Carbide Drill Bit - Cuts all steels.
Pro - Sharpened points wont "walk" like carbide tipped bit. Cuts all steel
Con - Sharp tip and fine edges can chip easily and ruin drill bit. Not for hand drills. Expensive!

For more information ***Removed***

 

[maltaron]

Dewalt "Extreme" drills may work. These have a small drill point and a milling type cutter to follow and are recommended for hand held use.

 

[Trazor]

Dewalt "Extreme" drills may work. These have a small drill point and a milling type cutter to follow and are recommended for hand held use.

I would think after 3 years, it's sorted.