Hi,
  I think that 1/2" or 3/4" thick aluminum base is gross overkill.  My
Lehman has a base 3/8" thick and is about 12" wide and 16" long.  I
think that this is plenty.

Bob Barns


Karl Cunningham wrote:
> 
> Jim --
> 
> Just to add a note to what Ted said...
> 
> As Ted said, the base should be pretty thick.  One of the things about
> Lehmans is the need to adjust the leveling of the base once in a while.
> You will undoubtedly have leveling screws in the corners of the base
> nearest the mass.  It is extremely sensitive to even slight turning of the
> leveling screws.  The sturdier the base the easier leveling will be, and
> the wider the base the finer the adjustment that can be made.
> 
> You may think this is overkill, but I'd try to find at least 1/2" thick
> aluminum, preferably 3/4" thick or more.  And it should be at least 8 to
> 10" wide.  The wider the better.  If you have room, make it 12" wide.
> 
> As Ted suggested, check surplus metal outlets for the aluminum plate.  If
> you can't find a piece the right size, they might cut it for you for a few
> dollars more.
> 
> Good luck on your project.  Be sure to post any questions you have to the
> list, and let us know of your progress.
> 
> Karl Cunningham
> La Mesa, CA.
> PSN Station #40
> karlc@.......
> 
> At 10:37 PM 12/29/1999 -0500, you wrote:
> >Gentlemen,
> >
> >My son and I are starting the process of building our first Lehman.  I have
> >visited numerous PSN web pages,  and would like to thank everyone who has
> >posted pictures and such relating to the construction.
> >
> >Would anyone out there care to supply me with just the basic dimensions of
> >the frame, boom, and base.  I will be using Larry Cochrane's electronics,
> >and would just like to get a little help so that we can get this project off
> >the ground.
> 
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