using calipers as scribes?

[desbromilow]

G'Day,

maybe I'm off base here, but I always viewed my calipers (vernier or digital) as measuring instruments, but I see more and more videos of people using them as scribes ( like the way a jenny or odd leg divider is used) - I've seen several videos with people using the external jaws, or the internal jaws to scribe steel for distances, scribe circles, etc.

I know there is no rule which says people can't use a tool how they like, but I also wonder if the manufacturer ever built these to be used that way. Most of my calipers are steel (stainless or otherwise) - not tungsten - I suspect the points of the internal jaws would be ruined, and the corners of the externals would rub away over time.

Is what I'm seeing common? is it recommended use?
I see things like that, and I cringe at the idea of letting others near my tools if they were to think that was acceptable practice.

thoughts?
Des

[Crusty]

I use my $30 caliper for scribing but never my Mitutoyo.

If you first coat the surface with a black magic marker then when you scribe you're only going through ink and there's little wear, but my cheap caliper still has the duty.

[desbromilow]

I use my $30 caliper for scribing but never my Mitutoyo.

If you first coat the surface with a black magic marker then when you scribe you're only going through ink and there's little wear, but my cheap caliper still has the duty.

I can understand using the jaws of a cheap caliper for lines in marker fluid/ whiteboard marker - but when you see youtube videos of people cutting through rust to make a line, you know the tool is being doomed.

[mklotz]

If you're going to cut the metal to size with an angle grinder, you don't need to worry about the minor errors incurred by translating the caliper setting to a proper set of dividers or marking out tool, e.g.,...

Marking out tool

[Crusty]

If you're cutting to a scribed line then thousandths precision shouldn't be expected so tip wear of a cheap caliper puts the error in the acceptable range for a scribed line.

A caliper is really just an approximater anyway and if greater precision is required then a different measuring device is needed.

I regularly wear out end mills costing in the same ball park as cheap calipers and with no cutter grinder to resharpen them that's a fact of life that I understand and accept going in. For that matter everything in a machine shop is doomed eventually.

[Frank S]

Cheap or not I don't use Vernier calipers as scribes, I guess I never got into the practice. What I do when I need scribe something is to measure with the Vernier then use a scribe to make the mark

[Eaglewood]

I’ve been a tool maker,gun barrel maker and aerospace sheet metal fabricator for a total of almost 50 years and I use my calipers as a scrib and cringe every time. Just can’t kick the habit��
Dick

[saplin]

I have had the same thoughts myself, to use a precision instrument in this way is a sacrilege. There are tools made for everything you need to do. Right tool right job.

[ibdennyak]

My shop teacher would......(insert proper punishment). I was severely chastised for using a 12 inch adjustable as a hammer.

[Toolmaker51]

I don't scribe with calipers. Majority of my calipers don't have knife-edge jaws; actually misnomer they are reduced width for narrow grooves and ID's, scribing is not advertised as a feature. Only instances I've seen, are where they are using instruments supplied by crib, NOT when paid out of pocket. There are scribe equipped calipers, the point is replaceable, other jaw [left side] is solid. Once in awhile you see them used in videos by fabricators like us.

There is a proper work-around. Time was, all decent vernier calipers were marked on the back with a pair of prick punch reflecting identical [~ +/-] space to graduations on reverse, easily within .003 of true measure.
My most frequent scribing is circles or larger radii, as in construction of geometrics, marks are ideal for that.
Many people unaware of them. Convenient for buyers, lest sellers upcharge for a common feature. Not hard to find in online auctions.
Straight lines I opt for surface plate and height gauge.