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Analyzing Slide
Trouble
There are so many causes of slide
trouble that it is valuable to know how to analyze the cause quickly and
eliminate the trouble. Correct diagnosis of the trouble is half the battle,
just as in correct diagnosis of auto or radio trouble. Usually the trouble
is minor but if you tinker and experiment blindly you'll have a major repair
job before you're through.
If the slides work well when dry but
begin to drag after oiling, look into the following:
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Maybe grinding powder used by
manufacturer when he ground the slides in has become loosened by the oil
and is acting as an abrasive. This fine grinding powder sometimes becomes
imbedded in the inside surface of the outside slides. As long as it stays
in the tiny pockets in which it has become imbedded, you have no trouble
with it. But when oil is applied, the particles are flushed out onto the
slides and trouble starts. The only remedy is to oil and clean, oil and
clean, until all the particles are removed. This may take weeks but
usually it will clear up in time.
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The other cause has been touched on
under "Cleaning Cork Barrel," above. Sometimes the original grinding
powder has not been well cleaned out by the manufacturer, or sometimes
dirt accumulates in the cork barrel. When the instrument is dry, the dirt
is not dislodged and causes no trouble. But when oil is applied to the
sides, the outside slides push oil up into the cork barrel and then pull
the loosened dirt out, coating the inside of the slides. This dirt spreads
over the slides gradually. At first you have trouble only with sixth
position, then you feel it in fifth, and so on up, until the inside of the
outside slide is entirely fouled, as well as the stocking on the inside
slide. The remedy is to clean out the cork barrel and keep it clean.
If your trombone works all right at first
after cleaning and oiling but begins to drag and bind after awhile,
investigate these possibilities:
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First hold your hand slides up to the
light and sight down their length. You'll probably be amazed at the dents
and dinges revealed. When the slides are inspected in the ordinary way,
you cannot see these dents, but when you sight down the slides they loom
up. The chances are that one or more of these dents are the source of your
trouble.
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Remember there is only about .003"
(three thousandths of an inch) clearance on a side between the stocking of
the inside slide and the inside of the outside slide. The dent may extend
only .001" to .002" (one to two thousandths of an inch) on the inside of
the outside slide. This may not give you any trouble when you start
playing. But as the trombone becomes warm it expands. The dent which gave
no trouble when the trombone was cool begins to drag when the trombone
becomes warm and expands. If you'll lay the trombone away until it becomes
cool, it may play all right again for awhile. Then, when it becomes warm
through playing, you experience the same trouble. The only remedy is to
have the dents and dinges removed. A repairman can run a ball down the
slide and locate the dent. This ball will be the diameter of the slide and
will rub or bind when it reaches a dent.
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More difficult to locate is another
source of trouble of the same nature. Slides become slightly sprung out of
parallel. Often this has been caused by dropping the hand slides on the
slide crook. The drop may have been slight, and when you picked the slides
up and worked them you may have concluded that no damage was done. But
when you get the slides warmed through playing, the slightest springing
out of parallel becomes more pronounced and the slides begin to drag and
bind. The only remedy here is to send the slides to a good repairman who
has the necessary precision tools to check the slides. If your repairman
does not have the necessary precision tools, the trombone should be sent
to the factory.
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