Wow Well... Where to start, It looks like you missed with a center punch on the really deep marks and well.. It looks like you and Mr. Dremel diden't get along lol.. That or Mr. Sawsall I'm trying to figure out which one you used. If I were you I'd just go to Lowes or Home Depot and buy a Hole Saw kit and save your poor case(s) some misery.
Sorry been away thats why the late reply. The hole was "cut" with a CNC milling machine with a 80mm cutter. The problem was that the metal flexed and became loose in the vice that was holding it sending it into the 5000rpm cutter. A hammer and a bit of bog has fixed it though.
I've had that happen on a CNC before. I was cutting a polycarbonate sheet with a CNC mill for a custom case. It suddenly jabbed down at the plexi send shards of metal & polycarbonate all over (even into walls). Thank god for safety masks. Big loss though since the sheet was worth around 80 bucks, and the drill bit 40 or so. All happened at school and lemme tell ya, the administration was not toa happy about the new holes in their walls.
schools are a bit funny bout that sort of stuff, I've seen the aftermath of a chuck of steel coming loose punching an unbelievably clean hole in a window and then slice thru the wall of a demountable classroom outside about 10 meters away before coming to rest pieced though a pupils seat. Just lucky the class was empty. Lathe got moved into a purpose built room later on, and was not allowed to be used until it was moved, and then only under supervision.
You can't just stop a CNC mill like that, pushing the emergency breaker kan destroy gears and tools that cost more than a years salary....
HI, In regards to the CNC; I am an expeirenced toolmaker[although not exceptional]. The HAAS mills and lathes that I am required to operate, will cease movement when feed hold is pushed. This just stops movement of all axis, not the spindle. The "CHICKEN" button will kill everything EXCEPT a rigid tapping cycle, which will continue to its end. Neither button will do internal damage to the machine. The damage done is by the "parts" flying around and the spindle beating it to death. This happens occasionally. Of course if one writes a bad move, the machine will go where you tell it and THIS will ruin the internals as well as other things. [This also happens occasionally] As for the blow hole; I have been considering buying this; http://www1.mscdirect.com/CGI/NNSRIT?PMAKA=04224481 a bit pricey but all you need is a pilot hole of the proper diminsion and some wrenches. It makes a very "clean" hole. I have smaller sizes that I have used with success.
Been there done that, on my own drill press hole punch is far easier and I don't have to remove everything from inside the case I have a large folding farm to do, so it is worth my cost.
well better the case than the pink fleshy thing thats standing next to it. I remember a lathe chuck flying off one of the many lathes we have in the workshop for Engineer Officers (merchant navy) and it made a VERY big dent in a wall about 15m away. the only thing that saved the boy (17yo) was that he had ********ed up and put it in reverse!
y.... e.... a.... h.... ummm.... well you see...... i think..... maybe.... you kinda destroyed..... the metal, it is well..... bent is the word.... but if you..... well.... meh.......