Serious - Drilling a square hole
 

VERY interesting cammed cutter chucked up in a CNC cutting chips in an aluminum test fixture.

Yup, drilling a square hole.

Slo Motion Video:

drill.mp4 video by randallwhitman - Photobucket

Dang, never would've believed it.
Thanks for posting this.

I watched the video and I still don't see how its possible... guess its not a true square. I had squares cut with a plasma burner a while ago into a piece of 3/16 diamond plate. Cool stuff.

it looks like theres a dual action in the drilling process

what about a mortise chisel? 4 sided chisel with drill bit in center - been around for ages.

It using two processes to make the square hole. Basically rotating and chiseling, but the thing is moving so fast that we can't see the tool doing the chiseling.

I suspect it pauses rotation for a fraction of a second, while it chases out the corner with the chisel part of the cutting tool, similar to a hammer motion.


Edited - Basically as Reg says above, the wood working tool for this has been around for ages. Still a cool cnc process.

2 nd edit, if I'd bothered to watch the end of the video, I would have seen this!

I have a mortiser for woodworking, not new tech.

If I remember correctly from a technical lecture (far too many years ago), it is theoretically possible to drill any multi-sided polygon shaped hole. The trick is to set up some kind of drive unit for the bit to perform a necessary similar type motion as shown in the video. The drill bit would always have one less cutting side than number of faces in the drilled hole, hence the 3 'sided' bit for a four sided hole. I would guess maybe it follows that one could not drill a 3 sided hole. At the end of the day, it probably has limited practical applications.

Cheers
JB

Old technology or not, somebody way smarter than me figgured that out!

The specially-shaped bit moves in an eccentric motion. It is impossible to drill a square hole with just rotary motion. This whole thing requires a special drill, not just a special bit.

N!

blah blah blah, end of the day, it's cool to watch, UNDERSTAND, and hence I posted it...........

cough cough, so credit to the guy who give 2 edits to his post before even watching to the end of the 2 minute video.

geez they show the rotary cammed XY motion diagram in the first :20-:25 seconds.


things must be needed faster in CA. Microwave not always better, slow roasted meat gooderer

If the hole is big enough you can just use a normal milling machine bit on a square path. Then you even get nice radius edges as well. This looks better than broaching, though.

Haven't you ever done a crappy job of drilling through thin sheet metal and ended up with a hole roughly shaped like this with a regular old drill bit.

http://upload.wikimedia.org/wikipedi...iangle.svg.png

I was just going to say, my drilled holes usually look triangular. So really I've already accomplished 3/4 of what they just did. LOL

Very cool - I'm thinking of all kinds of uses for that...

UK company Microbore makes tools that will do this and more....