[R-390] subchassis mounting nuts Q

[Roy Morgan]

On May 5, 2009, at 8:29 PM, Larry Snyder wrote:

> ...My 390A ('58 Motorola + possible mongrel-ism) has
> a couple of apparently stripped nuts in the deck where the back end
> of the AF chassis attaches.  Is there a decent fix for this,

Larry,

I assume that they are PEM nuts - specially formed nuts that are  
pressed into the chassis plate. Google PEM Nuts for details and  
drawings.

The problem is that to get a stripped nut out, you have to deform the  
aluminum that is holding it in, and any replacement nut will not  
clinch properly. The hole diameter for them to work right is  
critical.  You may be able to add a piece of aluminum below the hole  
to hole a new PEM nut, but likely there is something below there to  
prevent that.

Roy


Roy Morgan
k1lky at earthlink.net
529 Cobb St.
Groton NY, 13073