Hi,
Just to ask you which aerosol spray you would recommend for scratchy sliders?
I do a residency with an installed Numark mixer (you know the type, unmaintained, beer stained with no plastic knobs on the slider stalks) which has the annoying habit of passing through "dead" zones as the sliders are moved.
Any suggestions?

Thanks, Clive.

Hmmm its really time for a new mixer, or at least a good overhaul.

Switch/Contact cleaners offer a quick fix - the first time that they're applied they might well keep the faders crackle-free for say, a further 1000 hours usage - but they leave a residue - and of course dont remove the the dirt, dust, coating of theatrical haze/smoke...they just move it away from the contacts (a tiny bit)

Then, however, the crackling returns - you can apply contact cleaner again to temporarily resolve the problem, but this time, expect the "quick-fix" to only last maybe 950 hours, and so on...

I've heard guesses as to why the time that the fault stays away reduces each time, and the most plausable is the "High tide" idea. Which goes something like this: (Bare with me...its a graphic thing...)

Have you ever walked along a beach at low tide? You can see where the high tide mark is, as theres a load of seaweed stranded at the hightide mark. Now, imagine on your mixer circuit board that the first time that you spray in the contact cleaner all the dirt gets pushed away from the sliders in all directions - giving you an oval high-tide mark of shifted and slightly raised dirt (combined with residue from the contact cleaner).

The next time your faders go crackly and you apply more cleaner...this time the "fresh" dirt cant go as far as it did last time, it just makes the previous high-tide mark a bit thicker, a bit closer to the faders...

And the next time your faders go crackly and you apply more cleaner...again the "fresh" dirt cant go as far as it did last time, and again, it just makes the previous high-tide mark thicker still, still closer to the faders...

Until, eventually, the dirt can be moved away from the faders with contact cleaner.


Its feasable, even with so called "Low residue" cleaner, but I've never seen it proven - although everyone I've spoken to always agrees that switch cleaner/contact cleaner never offers anything more than a temporary fix.

CHEAP MIXER FROM EBAY!!

Hi Gang,
thanks for that.
Just to make it clear it ain't my mixer it is the clubs and I bet they would have a fit if I told them that their top of the range mixer that they bought ONLY ten years ago needed replacing....
I'm gonna get that contact cleaner and bill the club - they WOULD swallow that cost but not the cost of a new mixer.
Cheers,
Clive.

you mean you cant use wd40 on everything on the planet that needs fixing.

Halfords Silver

Many club mixers need their faders replacing after less than 2 years!! That includes Denon, Allen and Heath, Mackie..etc..quality. (not just cheapies.)

Most faders sound scratchy because the carbon film has worn away on the track. Spraying will usually work very briefly indeed and usually washes away the 'kilopoise' lubricant which they use to give the slider that silky feel. If a mixer is well-used in an installation then chances are, the faders are worn and need replacing. Numark use Alps and Taiwan-Alpha pots which need changing regularly.

A slider on a mixer which has been in storage for a few months may crackle due to dirt or dried beer and then you can bring out the servisol spray sparingly.

Actually, I was going to recommend WD-40! Trust me, works wonders - it really does!

You could try compressed air? If you think it's dust that is...