The technique of ripping a full length slot in a "coupler" piece 18" to 36"
in length is a well established method I used in joining 12 and 15 ft lengths
of 3" material. The assembly technique was to slot the coupler creating a
3/8" wide slot. Using large hose clamps this piece was compressed and
inserted half way into one side. Release the clamp and drill through the boom
into
the coupler along the line of the slot, and secure with #12 stainless sheet
metal screws (for the moment only along one edge). Tightening the clamp again
the other end can be inserted (liberally coated with WD-40)positioned, remove
the clamp, tap the boom together and proceed to drill holes on the second
side. On a 36" splice (30 ft boom) at least 4 screws on either side of the
slot,
and on each side of the boom should be sufficient.
If the "coupler" material is the same as the boom material (diameter and
wall thickness) one must be careful in compressing the cylinder as it may not
uniformly shrink in diameter. I used 3" x 0.087 wall boom material, and
2.875"
x 0.087 coupler material. I believe coupler material of this size is
available from Cubex / Tennadyne.
================================================
Message: 2
Date: Tue, 17 Mar 2009 14:07:12 EDT
From: Cqtestk4xs@aol.com
Subject: Re: [TowerTalk] splicing 3 inch boom material
In a message dated 3/17/2009 5:29:07 PM Greenwich Standard Time,
w5xz@att.net writes:
I am considering just ripping a full length slot, lengthwise of course, in
a
couple of 2 or 3 ft pieces of 3 inch, and stuffing one inside and wrapping
the other
outside with hose clamps, very snug, pop in a few rivets, and roll.
I did just that back in 90s with copies of the old KLM 5 el 20. It worked
really well. Just don't expect to be able to take the boom apart ever
again.
Bill KH7XS/K4XS
Regards,
Norm W4QN
**************Feeling the pinch at the grocery store? Make meals for Under
$10. (http://food.aol.com/frugal-feasts?ncid=emlcntusfood00000002)
_______________________________________________
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
|