if the plastic is ABS mould, it'll be fine to use alcohol, assuming it's isopropyl. (or the lesser of the evil, sugical spirits and methylated spirits.)
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@
op.
if the pad works electronically fine, but it's gunked up, strip the pad down carefully (youtube has vids if searched) and clean ALL parts that have the sticky shit on it, just don't dowse the fucker like a salem witch trial.
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a clean cotton rag and solution to hand should sort it.
have another clean rag for buffing.