Well, you have this flat stock that needs some holes drilled. How do you lay them out without spending too much time? If it needs to be really accurate, you probably want a good height gauge or surface gauge and a surface plate, not to mention an equally precise way to make the holes...
A fast and reasonably accurate way for less exacting work is to set and lock your calipers, scribe away, whack a dimple in there and drill. The downside is that the caliper tips wear away. If they´re your Mitutoyo ones, and your measuring tools arent free of charge, it sure isnt a wise way to scribe lines. You can sharpen the tips only so many times before they are ruined. Even if your tools where free, you´d upset the balance in the universe if you abused your tools like that. Dangerous...
Solution? Buy, steal (no, I don´t mean that!) or borrow a pair of these:
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| Vernier scribe - Nikon D200, 18-200 VR AF-S, built in flash |
They are pretty accurate with a verier scale and all. Carbide scribing pin, with plenty of stock for resharpenings. The roller is a bit cheap but it works with a drop of oil every now and then.
They actually cut a fine groove in the workpiece, so you can "click" down a prick punch where lines intersect. Then its easy to whack down an accurate center punch mark.
The scribers are really handy for laying out lines parallell to edges, to mark weld lines, to find centers of round or square stock, to mark keyway lengths, all those things you might be tempted to abuse your calipers for. Just the fact that the carbide tip holds up so well makes them worth having. If you make knife blades they are perfect for laying out the blade grind.
Since the distance is set between the inside edge of the pin and the roller, you can use them for outside measurements too. Its takes just seconds to measure, mentally divide, set and scribe center lines with the same tool.
What they don´t do very well is to replace odd leg (hermaphrodite) dividers for those times when you need them, mostly inside work.
They are quite useful for scribing wood, the sharp tip leaves a nicely cut line to guide your chisels.
Caliper abuser? Oh yes sir I certainly am, but I don´t use them for scribing lines. I have a proper tool for that!
Now where is my bottle opener? Never mind, I´ll just use my cal….
