Square Hole Drill Bit

[German_EE]

I think I may be missing something here, could somebody with metalwork expertise watch this for me and explain it?

[Skimask]

This video might show it a bit better...

[PA0PBZ]

That's neat. I expected it to make a lot more noise...

[calexanian]

Great for soft materials. Otherwise you need to use a broach in a press. Pretty standard machine shop stuff.

[SeanB]

You either have a drill with a separate hardened steel guide, or the drill itself is on an eccentric spindle with a guide at the top that is anchored to the spindle to force it to run in the square hole cut pattern. In any case it does cut a square hole with slightly rounded corners, and does quite well in soft materials. For harder materials you are better off using either a broach or a punch in a press. This works well for a few holes only, for high volume it is expensive both in time and tool wear. There you will use a punch, and then you can do a large number of holes, recesses for screws and panel display cutouts along with starting the box forming all at the same time on a large sheet that is positioned for the next stroke.

[calexanian]

Scotchman Ironworkers are about the most flexible unit for punching square holes in things. Simply Magic for fabrication.

[G7PSK]

This shows the geometry very well.

http://youtu.be/L5AzbDJ7KYI

[SeanB]

I want one of those Scotchman units........

[German_EE]

Please join the queue, although I would like a Scotchman in metric please. Thank you to you all for the videos especially G7PSK because once I saw that I realized how it was done. I should have paid more attention during metalwork classes.

[G7PSK]

Please join the queue, although I would like a Scotchman in metric please. Thank you to you all for the videos especially G7PSK because once I saw that I realized how it was done. I should have paid more attention during metalwork classes.

Here you go, made half an hour drive from where I live. http://www.kingsland.com/en/company/multi-60-70-80-95-125-140-175

This one is another company based in Europe never used one of this make wheas I have used a Kingsland, which is a good machine. http://www.nargesa.com/en/industrial-machinery/hydraulic-punching-machine-mx700

They are not cheap and are so heavy they will fall through the average house floor, you need at least 100mm of reinforced concrete under them.
The main problem with this type of punching machine is distortion OK for just one hole but if for instance you are making railings you end up with a curved bar if you turn the bar over every other hole for punching the bar is wavy, either way you have another procedure in straitening out the work piece, with the square hole drill you don,t get the distortion but it is not as fast in production but then there is not the time spent in running the bar through the pyramid rolls to get the bends out.