plenty vids on youtube pal other than that put plenty of salt on suck the moister out then scrape of the salt and rubish what comes with it then put a thin layer of salt back on works for me
i had one as a kid grate catapult i saw one on ebay not so long a go it was going prety cheep
some in the local gunshop for an alright price, guna pick one up the weekend i think!
ebay pal £3+£3