[pianotech] Build a Zapper

[Jeff Deutschle]

But, the more parts to the gadget the more fun it is!

When I saw the pictures I wondered what door bell needed a transformer
that size. A tube filament heater transformer makes sense. It is still
an applictaion of heat.

On Mon, Mar 30, 2009 at 7:45 PM, Delwin D Fandrich
<del at fandrichpiano.com> wrote:
> Before this thing becomes so technologically advanced it can't be put
> together without a built-in microcomputer chip let me remind folks that
> these things are supposed to be simple.
>
> Mine was built using a 6.3 vac filament transformer. Back in the day they
> were readily available just about anywhere really cheap. Now that vacuum
> tubes are no longer in common use it might be necessary to ask somebody at
> Radio Shack. Personally, I'd not go any higher than this in voltage.
> Remember these things are a short-circuit sort of device and using a lower
> voltage tends to hold the current down some. I put a simple push switch in
> so I could better time the application of current. An argument could be made
> that this is not strictly necessary but it also keeps the thing from
> shorting out when you lay the probe across the end of your screwdriver. The
> probe is made from an old set of tweezers broken apart and separated by a
> wood block of some sort. It ain't fancy. And it certainly ain't complicated!
>
> You don't really need any kind of indicator that current is flowing. You can
> kind of feel and hear the thing in operation.
>
> They are not, nor were they ever intended to be, a cure-all device. Nor are
> they the magical fix for the Dreaded Verdigris. They do one thing, and that
> only: they heat the center pin and dry out flange felt. In the process they
> tend to shrink and "iron" the felt some. Used correctly the effect is
> frequently long term.
>
> Like most tools it takes some getting used to. Yes, it is possible to burn
> the wood in the flange fork. But, using a 6.3 vas transformer, it does take
> some doing. I do remember encountering a few actions in which using the
> zapper did loosen the pin in the fork but these pins were already on the
> loose side and--though this is a guess on my part--I suspected the wood was
> a bit on the soft side. Not ever action builder used hard maple, you know.
>
> I stopped using it, not because it didn't work, but because I rarely, these
> days, work on actions with original action centers. If I come across an
> action with a bunch of sluggish action centers that needed a quick and cheap
> fix I'll probably start hollering at Ryan to get the thing back.
>
> ddf
>
> Delwin D Fandrich
> Piano Design & Manufacturing Consultant
> 620 South Tower Avenue
> Centralia, Washington 98531  USA
> Phone  360.736.7563
> Cell  360.388.6525
> Fax  360.736.5239
> E-mail 1: del at fandrichpiano.com
> E-mail 2: ddfandrich at gmail.com
>
>



-- 
Regards,
Jeff Deutschle

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