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Stiff tuning capacitor


 

Mine used to turn freely throughout its range, but now, it’s gotten kind of stuff. Annoying. Maybe a shot of penetrating oil on the “bearings,” or what??


Richard
WB5NEN


 

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Dear Richard,

?

Sorry to hear of your difficulty with

a stiff-turning capacitor.

?

I had not seen any prior posts from you

describing the component, so I’m not sure

of exactly how to proceed.

?

If you are talking about an air-variable

there are bearings on the front and rear plates

that need to be lubricated.

?

WD-40 will temporarily free it up, but the

best solution is to use a small amount of

molybdenum disulphide grease on a thin, thin

screwdriver, then to follow with a drop or two

of engine oil on the dabs of grease, then

follow up with moving the cap through all

its motion. The moly grease is conductive

plus it will work its way into the bearings.

?

You will see wipers on both ends that need a bit

of lube as well.

?

If you are talking about a vacuum cap, the actuator

screw can be removed and a bit of lube on the

threads and around the steel thrust washer will

work well.

?

Hal Mandel

W4HBM


 

Thank you. Yes, air variable. I do not have the moly di grease, but my neighbor has everything. I’ll check with him to see if I can get a dollop.?


R


 

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Zoro.com sells tiny tubes of it….


 

Be careful with WD40. It's flammable. I've had good luck with 0w-20 FULL SYNTHETIC engine oil. It also works well for clocks, guns, etc.
Bob W4JFA?

On Thu, Oct 12, 2023, 10:44 AM HaL Mandel <hmandel@...> wrote:

Zoro.com sells tiny tubes of it….


 

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3-in-One oil ... one drop.

W4DNR

On 2023-10-12 7:42 am, Richard P via groups.io wrote:

Mine used to turn freely throughout its range, but now, it’s gotten kind of stuff. Annoying. Maybe a shot of penetrating oil on the “bearings,” or what??


Richard
WB5NEN


 

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Hi Don,

?

That’s exactly what Lt.Cmdr (Ret.) MSRN Atilla the Hun

advises me from time-to-time.

?

Hal

?


 

Well, I pulled out one of my blunt-needle syringes that I use for applying really small amounts of stuff, and hit both bearings of the air variable with a drop of Kroil, “The oil that creeps.” Love that stuff, but not cheap. Anyway, the cap is turning freely now. But I’m pretty sure this is a temporary fix. Time will tell. Prob need real lubricant in there.?

Richard
WB5NEN


 

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Where I used to work we referred to Kroil as ‘weasel piss’ and ‘millwright’s aftershave’!

?

Mod-U-Lator,

Mike(y)/W3SLK

?

?

?

From: [email protected] [mailto:[email protected]] On Behalf Of Richard P via groups.io
Sent: Thursday, October 12, 2023 4:50 PM
To: [email protected]
Subject: Re: [ham-amplifiers] Stiff tuning capacitor

?

Well, I pulled out one of my blunt-needle syringes that I use for applying really small amounts of stuff, and hit both bearings of the air variable with a drop of Kroil, “The oil that creeps.” Love that stuff, but not cheap. Anyway, the cap is turning freely now. But I’m pretty sure this is a temporary fix. Time will tell. Prob need real lubricant in there.?

Richard
WB5NEN


 

But it seems to work well!