Quote:
Originally Posted by neo
I am completely new to metal forming. I have galvanized steel sheets of 26-30 gauge. I am trying to get answers to the following questions.
1) How to cut a square hole of size 3mm x 3mm?
2) How to extrude punch a square hole of size 3mm x 3mm by about 3mm?
3) How to bend 3mm x 3mm hanging square feature by 90 degrees?
Excuse my terminology this is the best I could do to describe as an outsider to metal forming.
All the punch-die sets, cold chisels, brakes that I find on the market seem to work with larger feature sizes. But looking at the USB cable plugs, it seems 1) and 3) are possible.
Can someone please give me a few pointers?
Thanks
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For this size sq. hole you need to:
Lay out on the sheet with a dye/paint of some contrasting color, and add accurately scribed lines (w/sharp nail or punch).
Punch centers w/small punch (keeps drill from wandering around the neighborhood before finally planting itself wherever in yer part) and then Drill two holes at opposite corners, centered so that hole edges fit within your scribed lines. Choosing twist drill diameters within but not exceeding, and allowing for your own wobbles when accomplishing this task is a personal choice.
Clamp drilled piece to table top, hole off the edge, out in space.
Using a small tapered square file with nice round handle, push file through hole and begin to open round holes into square ones. Keep going until you get to your scribed lines.
Sand with sandpaper or dress rough/sharp edges with fine flat file.
Check your whatzit to see if it goes through the new hole you have made.
But... if you already have a nice small (Whitney) punch/press, you can order up the punch/die set, install the upper and lower dies, locate your part in betwixt said dies, shove press and "pop" goes your nice sq. hole.
With good hand skills you can lay out said square, and then sharpen your small chisel to be a sharp long-angle cutter, and take your small ball peen hammer and whack the chisel around the perimeter 4-5 times, finally penetrating your metal. Best using end grain of a chunk of FLAT hardwood for this anvil work.