[ARC5] Tuning Capacitor Removal - Help, please!

[Dennis Monticelli]

I have had good success by making a simple custom press block out of scrap
wood and then apply the steady controlled pressure via C clamps.  The custom
block puts the pressure just where you want it and not where you don't want
it.  The wood does not mar the aluminum.

As you say, think about where the bending pressure must have come from and
try apply the opposite force.

Dennis AE6C

On Sun, Mar 20, 2011 at 11:03 AM, Mike Hanz <aaf-radio-1 at aafradio.org>wrote:

> Good advice from Dave and Ken.
>
> On items like this, I always start out with the "equal but opposite"
> ploy, but it assumes you have some method that you can use to give slow,
> graduated pressure to whatever is bent.  A good example is in the top
> two photos at http://aafradio.org/garajmahal/BC-AA-191.htm where a steel
> strut needed to be straightened.  On the command receivers, the panel
> metal is very soft, as Ken noted, so it does make it a bit easier.  One
> technique that you may be able to accomplish is to clamp the receiver on
> the table of a drill press - upside down in your case - using soft
> protection between the receiver and the steel table.  Then chuck a long
> 1/2" bolt in the drill chuck.  You should then be able to preposition
> the head of the bolt at the tip of the bent down antenna post and begin
> to apply some pressure to it.  Then look at the metal surrounding the
> insulator.  If there are no ripples being formed in it, then move the
> downfeed lever a bit more.  You do risk breaking the ceramic insulator,
> but they are pretty resistant to steady pressure like this...it's impact
> that they don't like.  Just take your time and watch the area
> surrounding the insulator for distortion.  Once the insulator is
> completely horizontal again, you can make a determination if further
> work is needed to flatten the panel...aluminum is unfortunately a
> "stretchy" metal, so ripples are sometime unavoidable, but I would try
> the slow pressure approach first - you may be fortunate.  Another
> approach would be to clamp the receiver on the edge of a workbench and
> do something similar with a large C-clamp.  Once you get the antenna
> post straight again, you can decide whether you need to do more, which
> essentially says you will have to remove the capacitor per Dave and
> Ken's advice.  If you do have any ripples, then a bolt and nut with a
> couple of washers can be threaded through the insulator hole and used as
> a compression flattener.
>
> Let us know how it goes,
> Mike  KC4TOS
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