[CQ-Contest] Aluminum fatigue cracks and scratches - treatment?

[K3BU at aol.com]

In a message dated 8/5/04 6:13:52 PM Eastern Daylight Time,  
andersen at simnet.is writes:

Sanding  down the crack sure makes it disappear, but at the same time
I would be  thinning the wall of the tube a little in this place.   Any
comments?





Depends what kind of crack it is. If it is from the stress by fatigue, it  
would propagate, will get bigger and eventually fail. Fatigue crack is usually  
caused by the vibration. In that case you need to remove "resonance" by guying 
 in different place or inserting dampening rope inside the element. It would 
be  advisable to put the brace around the area with crack. If possible use 
aluminum  welder and weld/fill the crack and area around it. 
Sanding would help if the crack was just on the surface, but most likely it  
would be across the thickness of the tubing, in which case is too late. Use 
the  brace or weld or use aluminum solder to fill it.
 
Yuri, K3BU.us
_www.computeradio.us_ (http://www.computeradio.us)