zeroing an indicator

can anyone help me get the indicator to point north onto zero?
it's a starrett 25-341


thanks

Rob

It looks correct to me.

AGD Specs stipulate that the hand rest at the 9 o'clock position.

http://longislandindicator.com/p2.html

If you want to zero it, loosen the knob that keeps the bezel from turning and turn it until it is where you want.

Rob the knurled nut at about where the 20 is will loosen the bezel and alow you to twist the bezel to "Zero" the indicator.-matt

Dial-type indicators are made this way so that you can start at zero with some pre-load already in the movement. It would be very hard to accurately set an indicator to zero if it didn't have some preload already on the stem.

Rob Mueller said:

can anyone help me get the indicator to point north onto zero?
it's a starrett 25-341


thanks

Rob

Click to expand...

Sure. Place indicator tip against surface to be indicated; adjust crosslide/quill/indicator stand until pointer is at zero. The pointer isn't supposed to be on zero, when the indicator is 'at rest'.

RAS

Rob,

As others have noted, your needle should be at 9 o'clock with no contact (that's the way they are designed to work best), but if you look inside the indicator thing you will quickly figure out that by loosening things and slipping one or more teeth on the spindle rack that you could get the 9 oclock setting several ways. For example, you could have the big hand at 9, and the little (tenths) hand on 0, or .1, or .2, etc. The fact that your tenths dial seems to be correct (about 27 thousandths shy of 0, same as your big hand) indicates to me that you have a correctly adjusted indicator.

Your indications should not be too accurate and repeatable for the first 5 thousandths or so (from 9 to 10 oclock) as the spindle comes off the rest(this is normal!), but thereafter I think you will find that this is a very durable and accurate indicator if it's kept clean.

Jim

OK, OK. I bow to the consensus. I'll leave it where it is.

thanks to all.