[TowerTalk] (no subject)

[K7GCO@aol.com]

In a message dated 16.03.00 14:51:40 Pacific Standard Time, aa4lr@radio.org 
writes:
<< On 3/16/00 4:51 PM, K7GCO@aol.com wrote:
 
 >The above illustrates that aluminum rivets just do not have the 
 >strength to support the stresses of aluminum tubing in the wind 24 hrs a 
 >day. 
 
 Yeah, right! That's why they've been used almost exclusively on aircraft 
 since the DC-1!
  >>
The home use hollow "pop rivets" of soft aluminum are not the same as 
aircraft rivets which I've inspected thousands of.  The evidence is "POP 
RIVETS" are coming lose in antenna elements--NOT "AIRCRAFT RIVETS" which use 
a bucking bar.  These are not flat plates with many rivets to make it 
equivalent of being literally welded. Why are you defending the "Pop Rivets" 
that have been widely discussed in many many posts when they are not holding 
or maintaining low RF resistance?  Why has force 12 even switched to bolts in 
bracket areas?  Many others are saying the same thing.  When I retired I had 
a file of over 2000 pictures I took at Boeing of rivets, bolts and other 
related structural attachments for failure study and outside air smoothness.  
It was used to influence better design.  I had them of other airplanes--like 
in current use.  What have you got for the evidence of "Pop Rivet" use on 
antennas?  Voice your doubts to those who have the rivet problems.  Perhaps 
you should look at them.  I don't have them--I just observe their weaknesses 
in structural test jigs and antennas.  I do use lots of hollow soft pop 
rivets in SO-239s and other applications where they work just fine. 

Would you believe they are putting Gidean Bibles on the "Eagle Hardware 
Hollow Soft Aluminum 1/8" Pop Rivet Planes" you mentioned (I really believe 
they have the right rivets). That's so you can Cram for the Finals on the way 
down.  It's the Readers Digest Condensed Version of Flip Cards of the 10 
Commandments, 23rd Psalm and the other quickies.  That's all the time you 
got.  A parachute, inner tube, can of screw grease and shark repellent would 
also be useful as carry on luggage. The FAA can't do it all.  Rivets are fine 
if you use the right ones and plenty of them.     

Since I have a mill and lathe I'm thinking of making up Aluminum clamps like 
used in rifle scope mounts just to have the same metal but still grease them 
and a cleaner design in the effort to build a better design.  I have also 
made knurled and inside tapered threaded collars with a fine thread cut with 
a taper attachment copied after what was on the old Workshop Beams of the 
40's and still have--a great design.  I've made 4" long knurled handle no 
wrench collars to squeeze the tubing for portable antennas.  Since large 
diameter tubing often used is still .058" wall and available pipe tapered 
threads for that diameter are too course, I used a fine tapered thread for 
great compression leverage just by hand.  With Anit-Seize with aluminum 
particles on the threads it is very powerful squeeze and highly conductive.  

I got your first E-mail to me and TT and even the 2nd one to me and TT--2 
minutes later.  I bet you use 2 rivets in everything you build.  One E-mail 
to me directly would have been ample ample.
K7GCO

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