Digital Calipers

[Cory]

Originally Posted by EricH

Actually, the bolded portion is one purpose of a set of calipers. You're just supposed to use that function with Dykem on the part, though--the calipers scratch that away easily.

I use dial calipers myself--that's what I have. They don't need batteries to run.

Regardless of their ability to scribe lines, I'd be pissed off if I found someone using my $165 pair of dial calipers to scribe lines. It's poor practice to utilize a precision measuring tool as a cutting tool of sorts. If it was a $20 pair, sure go ahead. Something that expensive and nice you're generally not going to be using to do setup work as you want it to maintain it's level of precision.

[MrForbes]

Cory's talking about what students actually do with calipers, Eric is talking about what they should be doing with them. Not scribing lines, but making a small mark which you then make more pronounced with a real scribe.

[JD Mather]

I read part of this and didn't bother to read the rest.

Get digital - forget all other arguments.
Accuracy is same for all (undamaged instruments) for student work (if you need more accuracy than .001" or 0.025mm then you are using the wrong tool. (maybe micrometers instead?)

JD

Taught Machine Tool and CNC for 5 years.
Worked out on the shop floor for 8 years before that.
Certified Journeyman Machinist