At work we have a huge Cincinnatti horizontal mill. When i joined the company it was deemed innoperable due to electrical issues. I later found out the elctrical issues meant that the plug socket where the DRO plugs into was bad. The machine itself ran and the DRO could be used if one pulls an extension over and plugs the DRO in. The real excuse for being down was people were afraid to run the thing....So as a newby I got tasked with cutting keyways on a 6''X22' shaft on this mill. No problem, I have used smaller machines like it in the past so I gave it a go. So I set it up and strapped the shaft down to figure out where to place the clamps etc. I get ready to cut and get pulled away for a second. Before I walked away I started the spindle and turned my back. I figured I would idle the spindle before applying cutting pressure. I knew the X feed was off but didn't realize the Z feed was engaged. The lever is right to the power feed. Another machinist saw what was happening but froze as he was scared to death of this machine. The cutter plowed into the shaft and melted into it about 1/4'' . The cutter actually stuck out of the BT-50 collet about 2 1/2'' but by the time I got to it, it was barely 1/4'' sticking out. The actual collet was rubbing to the point it pushed the shaft off the clamps. This machine is very powerful and stout... Luckily I had decided to use a cutter that used two carbide inserts and it was not the bottom cutting type. I thought for sure I killed the shaft and the collet but to my surprise, I was able to remove the remains of the cutter and clean up the collet. As for the shaft it required a bit of welding and grinding to remove the boo boo. There was a potential of $12,000 loss for the shaft plus I have only been working for about two weeks when this happened. This was last week by the way. I have six more shafts to cut so I have taken the liberty of cleaning the areas around the levers and marked them with a sharpie to get a better visual of where the controls are; at least the neutral positions. I was later told by one of the weldors that no one else wanted to run this machine because they were scared of it. As simple as this machine is, it could easily make a hot mess in a hurry if gets away from you in a second. Now I kind of enjoy running it and it will be even better when I make a jig to cut keyways on it. Hopefully once it's properly set up others won't fear it and try to use it.
