Yes, apparently combination of brass and aluminum is OK if properly stored in dry conditions or used away from moisture and hygrosocpic material such as dust.  The after-market copies of the mil. spec. spin knobs are cool, but as you say, not acceptable for military use.  Still wondering where they came from.  Mke, W6MAB (occasional lathe operating goober)

On November 1, 2021 at 2:09 AM Mike Feher <[email protected]> wrote:

Under normal circumstances there is no problem. Probably would not be approved for mil gear. For corrosion to set in an electrolyte needs to be introduced. It could be as simple as water. 73 – Mike

 

Mike B. Feher, N4FS

89 Arnold Blvd.

Howell NJ 07731

848-245-9115

 

-----Original Message-----
From: [email protected] <[email protected]> On Behalf Of MICHAEL BITTNER
Sent: Monday, November 1, 2021 12:32 AM
To: Michael Hanz <[email protected]>; Brian Clarke <[email protected]>; Adam Castellani <[email protected]>; [email protected]
Subject: Re: [ARC5] Tuning Knob

 

I picked up this Cardwell var cap at the TRW swap meet yesterday.  Note all the Brass-on-Aluminum faying surfaces.  No signs of corrosion on this decades old component.  So how does Cardwell get away with what "no chemist or physicist would do"?  Mike, W6MAB

 

> On October 31, 2021 at 9:54 PM Michael Hanz <[email protected]> wrote:

>

>

> Agree.  Nicely made, but....

>

> On 10/31/2021 9:33 PM, Brian Clarke wrote:

> > No chemist / physicist would put brass and aluminium together;

> > hence, not a production item.

> > So, probably after market, home made. Possibly a once-off.

> > 73 de Brian, VK2GCE