Calibrating a Starrett 98-4 Level
 

Just got a used Starrett 98-4 precision level which is accurate to
..005" per foot. How do I calibrate the level? It has a screw on one
end that holds one end of the level and a threaded stud on the other
that hold the other end of the level. The level is held captive on the
stud in between the nuts on the threaded stud. Mine was loose when I
got it and I need to know how to get it back in trim and check it for
accuracy. Thanks, Steve

In article ,
Steve wrote:
Just got a used Starrett 98-4 precision level which is accurate to
.005" per foot. How do I calibrate the level? It has a screw on one
end that holds one end of the level and a threaded stud on the other
that hold the other end of the level. The level is held captive on the
stud in between the nuts on the threaded stud. Mine was loose when I
got it and I need to know how to get it back in trim and check it for
accuracy. Thanks, Steve

Not really "calibration", but more "zeroing".

What you do is find a good stable flat surface (a surface plate
would be nice) and set up a reference stop for one edge of the level to
be against so your angle is repeatable.

Then place the level against the stop, and note how many lines
it is off of center. Then reverse the level end for end, and check
again. It should be the same number of lines off for each orientation.
Make your adjustment until you have that consistent. Once that is done.
you can be assured that if the bubble is in the center, the surface is
level (at least, within the capabilities of that particular instrument).

Note that there are far more sensitive levels. Starrett's
"Master Precision Level" (No. 199) is 0.0005"/foot, and thus is much
more touchy to adjust.

Good Luck,
DoN.
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Hi,
Find a flat, stable surface that is reasonably level. A surface plate or
smooth machine table will work. Place level on the surface and mark location
or place some heavy parallels around it so you can remove the level and put it
back in the same exact location. Adjust the level until the bubble is
reasonable centered. Reverse the level (swap ends.) Continue to refine the
adjustment until the bubble reads the same when the level is reversed. Really
does not take too long.

Mill

Subject: Calibrating a Starrett 98-4 Level
From: (Steve)
Date: 8/19/2004 1:28 PM Eastern Daylight Time
Message-id:

Just got a used Starrett 98-4 precision level which is accurate to
.005" per foot. How do I calibrate the level? It has a screw on one
end that holds one end of the level and a threaded stud on the other
that hold the other end of the level. The level is held captive on the
stud in between the nuts on the threaded stud. Mine was loose when I
got it and I need to know how to get it back in trim and check it for
accuracy. Thanks, Steve