Gentlemen,

I am now able to repeatedly achieve at least a 15.3 sec period on my Lehman.
I am now using .020 music wire for the attachment from the boom to the lower
part of turnbuckle,  and .015 music wire from the upper part of turnbuckle
to the upper pivot on the pipe frame.  I am still using the 1/2" threaded
brass rod, sharpened to a point on the pivot end.  The point pivots on the
polished head of a Grade 8 hardened steel hex bolt.  This bolt head has no
dimple.  I found that the dimple was causing a LOT of friction.  I am quite
sure that with a little more fine tuning,  I will be able to easily achieve
a 20 sec. period.

Just my 2 cents.....

Jim Martin
New Haven, Indiana


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