-The zinc plating on
the steel components
of Hammond organs sometimes can grow metallic fur or ''dendrites''
. I have no idea what the actual growth mechanism
is (if you know, please enlighten us!). Heat and humidity can tend to speed the growth
of dendrites
.
+The original HammondFaq identified
the MetallicFuzz which sometimes grows inside
of Hammonds as "Cadmium Dendrites"
. After much discussion it appears this fuzz
is actually composed
of Zinc not Cadmium
.
-Even scientist don't know the actual reasons for dendrite growth. The gravity induced convection makes it impossible to track the dendrite growth.
Therefore they made an experiment
, that flew with
the space shuttle:
-Isothermal Dendritic Growth Experiment (IDGE). One thing is known for sure: the solified zinc surface shows the dendrite structure already. And the fresh zinc surface is chemically active. If humidity is high, a zinc solute can occur, which leads to the growth. A way out
of this is to plate
the surfaces with chrome
to passify the zinc. A simple lacquer layer does the same
.
+Therefore, the contents
of the page have been moved
to ZincDendrites
.
-In any case, the ''dendrites'', being metallic and therefore ''conductive'' can cause all kinds of mischief in your organ. Dendrites are often the cause problems in the vibrato [Scanner], and the [Vibrato] switch assembly, where they cause MotorBoating, or choppy vibrato; and also in PercussionSwitchAssembly, and in the manuals, where they can cause the [Percussion] to misbehave, or can cause strange ''hums'', funny cross-talk like sounds and other wierd symptoms.
-Dendrites can also grow in/on the swell capacitor (where they'll cause terrible noises.)
--------
-!Zapping
-
-Many people claim they have successfully cured dendrite problems in all of these places by "''zapping''" --- putting enough current through the little whiskers to burn them out.
-
-Some people advocate the careful use of reasonably low voltages (''e.g.'' nine volt "transistor radio" batteries) to zap dendrites, while others swear by using the ''B+'' supply (a few hundred (__''!''__) volts) as a source of zap.
-
-__WARNING: ''Zapping can clearly be hazardous to the health of you organ. Please make sure you understand what you are doing, and appreciate the possible consequences before you attempt it.''__
-
-I, personally, am extremely leary of ''zapping''. I have used the nine volt battery approach to cure percussion problems which were caused by short in the upper manual. In my experience this is a temporary fix. The shorts tend to recur (usually after moving the organ).
-
-Also, see ManualZapping.
-
-------
-
-Clearly the ideal fix for dendrite problems is to open up whatever component has the dendrites a clean them out. (Compressed air, shop-vacs, and sticks covered with double-stick carpet tape have all been recommend as useful tools for this task.)
-
-
-See also HowToRebuildTheVibratoScanner
-Reportedly, cadmium and/or camium oxide is highly toxic and/or carcinogenic. Fortunately, however, it's also been reported that the whiskers which grow
in Hammond organs are zinc, not cadmium. I'm not 100% certain about any of this though, so you might want to be careful around that fuzz
. (If you know something more, add it here, please!)
+Reportedly, cadmium and/or camium oxide is highly toxic and/or carcinogenic. Fortunately, however, it seems there is no cadmium
in Hammond organs.
