Hi Folks,   This is the basic process I use to adj. a Lehman.
1.  I assembly everything and level everything.    Once this is =
completed the vertical part of the frame is plumb.   The boom, and frame =
are parallel with the earth and the boom is resting on the centerline.
2.  I time the period and start raising the front adjusting leg, =
tweaking the side adj. legs as necessary to maintain the boom on the =
center line.  When I get a stable 20 second period I am finished.

These are my questions:    When I perform this set up, the vertical =
frame member is now tilting backward, and the mass end of the boom has =
be raised.  Now the boom is no longer parallel to the earth.

1.  "What would happen" if I extended the wire support, lowering the =
boom back to parallel to the earth, but not changing the vertical =
member.   To my knowledge I have never done this, I just leave the boom =
with mass end raised via the front adj. leg.

2.  Should I make this adjustment, returning the boom to parallel, by =
lengthen the support wire?

I have tried it, but the adjustments are so small I can't measure the =
results.








Hi Folks,   This is the basic =
process I=20
use to adj. a Lehman.
1.  I assembly everything and =
level=20
everything.    Once this is completed the vertical part =
of the=20
frame is plumb.   The boom, and frame are parallel =
with the=20
earth and the boom is resting on the centerline.
2.  I time the period and start =
raising the=20
front adjusting leg, tweaking the side adj. legs as necessary to =
maintain the=20
boom on the center line.  When I get a stable 20 second period I am =

finished.
 
These are my =
questions:    When=20
I perform this set up, the vertical frame member is now tilting =
backward, and=20
the mass end of the boom has be raised.  Now the boom is no =
longer=20
parallel to the earth.
 
1.  "What would happen" if I =
extended the wire=20
support, lowering the boom back to parallel to the earth, but not =
changing the=20
vertical member.   To my knowledge I have never done this, I =
just=20
leave the boom with mass end raised via the front adj. leg.
 
2.  Should I make this adjustment, =
returning=20
the boom to parallel, by lengthen the support wire?
 
I have tried it, but the adjustments =
are so small I=20
can't measure the results.
 
Thanks, Ted