[Bazz4CQJ]

There has been an enormous push towards using water-based cleaners over the last 30 years and while some are very effective, the risk of corrosion lurks in the background. Quite a lot of the products are fairly alkaline. Others, while apparently pH-neutral could encourage corrosion if dissimilar metals are present, especially if you start pushing up the temperature.

I used ultrasonic baths a lot at work, but the weirdest result I ever saw was at home when I put a salvaged B7G valve base in to a neutral aqueous cleaning solution. Leaving it for ~15 minutes, I returned to find it had turned in to a "right mess".

I imagine that an AR88 gearbox is quite a valuable object, probably made of a number of different materials. Immersion in an aqueous solution is probably not the safest way to go. I wonder if a paint brush and a drop of paraffin might be a simpler and safer approach? You can bet that the gear box was not ultrasonically cleaned at the point of manufacture.

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