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The current way of making perforated angle is fairly time consuming: print, cut, puncture and attach labels, saw long angle into pieces, and then center punch the pieces from which lables will be removed - for example, those that will be used as linear rails. Most printers do not print the labels to exact dimensions, forcing to resort to cheats and workarounds. Then there is also drilling, however the current approach is to drill holes on demand.

My thoughts on improving the angle preparation process went mostly in two directions - a) build a contraption for center punching the angle (with 6 or 12 automatic center punches), or b) go traditional manufacturing route and get lots of angle drilled on large CNC machine, which would probably be optimal for large volume. To investigate the possibility of punching contraption, I ordered a couple of automatic center punches. On the picture below, center punch on the left costs $4 while the other one costs $30. Indeed, you get what you pay for. The $4 punch doesn't strike 9 times out of 10 (approximately), while the Starrett 819 punch reliably strikes every time. However, the force required to trigger the punches is significant in either case, to the point that I'm wondering whether the motor with leadscrew drive will have enough juice to trigger just one, let alone multiple center punches. 

The neat thing about the Starrett 819 automatic center punch is that it has a self centering sleeve around the pin, 5/16" in diameter, tapered at the end. This makes it very convenient to punch the blank angle using a template made from perforated angle - see the pics above. The accuracy is acceptable if center punch is held perpendicular to the punched surface. Only three 24" perforated angles are needed to quickly make lots of center punched angle blanks 24" long - see the pictures.

Because new UHMWPE sliding element pads are more sensitive to burrs, I need to figure out how to quickly deburr the holes (maybe with a countersink bit or by using unibit to drill); then I'll update the perforated angle section in the docs.