As they say, you get what you pay for but I just ordered one of these cheap gauges:



They are on sale here for $7.39:

http://www.newfrog.com/p/black...-pad-wear-58962.html

1" of travel, I am planning on gluing a magnet to it to measure travel. It'll be interesting to see if it works well.

Anyway, it is on sale for a couple of days so I thought I'd post it if anyone else might be interested. Just know it is less than $8 so if it turns out to be a true POS don't yell at me, you knew what you were getting in to LOL!

Ad says it's accurate to .0005 in. If it is truly accurate that's a helluva bargain. I'd likely get two.

Looks strangely similar to one of my Mitutoyo calipers. Heck $7 and free shipping- I'll give it a whirl..

Mark

ordered.. thanks, got an extra for a gift too.

FYI it's the same head as the Franklin (Midway) unit


rich

Yes you do get what you pay for. My first set of digital calipers were quite expensive Mitutoyo brand ones, same brand as my dial and standard vernier calipers, The digital set was excellent with perfect repeatability, max and min holds when measuring a number of same articles e.g. bullets, and ability to connect to a printer. Unfortunately one of my sons clown mates dropped them and broke the screen. Bought a cheap but well made set online and while they work good enough for simple measurements they are not as smooth for setting to a size and locking to enable measurement of say cartridge OAL etc.

The expensive set would allow travel in .0005" steps using the thumb wheel, the cheap set more like .050" and don't have a thumb wheel so it takes a bit of back and forward to set a specific jaw gap.

I pretty much thought of using it for fine measurement on my lathe saddle- not so much for absolute measure, but incremental measurement. As long as it doesn't stick or skip, it should work

quote:

Originally posted by Dulltool17:
I pretty much thought of using it for fine measurement on my lathe saddle- not so much for absolute measure, but incremental measurement. As long as it doesn't stick or skip, it should work

And that is the principal use for a tool of that claimed accuracy. Most folks don't remember for example that a 25" long piece of 4140 steel lengthens or shortens approximately .001" for every 5° of temp rise or fall. Makes .0005" accuracy almost meaningless for most folks unless they measure things in a carefully temperature controlled environment. And as life is seldom simple, the modulus of thermal expansion varies for different steel compositions and still more for some other metals.

Even then, to be accurate to .001", they need to know what the length was at a particular standard reference temp and then use the modulus of thermal expansion to correct the readings for other temperatures.

Of course, for most shooting applications, .001" has little meaning in daily life anyway.

But it does give us benchresters something to fuss about.