[R-390] R-390 Knobology Question

[Flowertime01 at wmconnect.com]

Barry,

One school house idea was the knob shape let you get a hold of it even while 
wearing gloves. I have seen R390/A operated in Korea where it was done with 
gloves and you did not put no head phones on your bear ears.

The MC knob could take some massive (R390 Wrist) force to move over an over 
set detent. Set screws would will not give you enough friction and would be 
forever failing. 

I have on occasion had to file / burnish a burr on the MC and KC shafts to 
get a front panel off. The idea was that the clamp knob would not put burrs on 
the shaft like a set screw will.

Die cast knobs in the 1950 era were cheaper that Bakelite or plastic. The die 
cast was also expected to be resistant to known life forms. Further the die 
cast was expected to freeze and vibrate in shipping without failure. Most of 
the design was driven from lessons learned the hard way out of WW II. 

The tax payer wanted cheep stuff. But the stuff was not supposed to kill our 
own fellows.


You are right there were lots of other good designed knobs in production. Why 
not just go with common parts? I just retired out of Raytheon after 20 years. 
Every day I was working with young engineers that acted like the world was 
created just this morning by themselves. They had no clue what's in use and 
production. Sur get me a new NATO Stock Number for these stainless steel 10 x 32 x 
1 inch fasteners for the parts manual. What! you mean I can buy these from Mc 
Master Carr and still list them in the parts manual with someone else's NSN 
and not actually buy NSN parts for the assemblies? 

Have some ever had the chance to look at NSN Micro Fitch and see how many 
times common hardware (and electronic parts) have been duplicated in the 
inventory system.


> Roger KC6TRU
>