Replies

1. 
   calvin | Apr 23, 2015 05:01am | #1

   Dan

   Hilti 

1. 
   gfretwell | Apr 23, 2015 11:12am | #2

   Looks like rats

1. 
   Mike_Mahan | Apr 23, 2015 11:56am | #3

   You're right.

   I've heard NYC rats do this all the time...in just minutes.

2. 
   cussnu2 | Apr 23, 2015 01:45pm | #4

   They are dead straight which makes me think it was somehow mounted as a horizontal boring machine

1. 
   oldhand | Apr 23, 2015 02:54pm | #5

   yeah.. I can't see whatever bored that being a hand held tool.

   Also wonder how they managed to miss any steel.

1. 
   junkhound | Apr 23, 2015 06:31pm | #6

   billy posted a pix of the tool on bt3 - big cup drill

3. 
   renosteinke | Apr 23, 2015 09:18pm | #7

   Small? More like "Routine"

   Looks like a typical job for any concrete core drilling firm.

   Such firms mount the drill in a sort of 'drill press,' that mounts to the wall with as few as a single 1/2" bolt.

   The rig uses a diamond-tipped core drill bit (think 'big toothless hole saw') that operates witout hammering or vibration. Often use with a water flush, they can also be used dry. Such bits go for about $100 per inch of diameter. The bits have no problems cutting through rebar - and I think I see a bar in the middle of the pic.

   Such equipment is readily available, both new and used. Plus, coring companies are as vulnerable to burglary as any other business.

   I estimate that the core drilling took about 6 hours.

1. 
   DanH | Apr 23, 2015 10:59pm | #8

   Yeah, if you read the article (link at the start of my post) the story indicates they did the job in probably two sessions of 8-10 hours each, including time required to cut through some steel doors, and time to actually raid the safe deposit boxes. 

   I don't see any holes for the attachment bolts, but they might be off the edge of the picture, or perhaps they secured the rig some other way.  Apparently the rig was a Hilti DD350.