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What size magnets should I use when I go to magnetize my fexes arms and weapons?
I use these K&J Magnetics - Products for the body and larger, heavier claws and weapons (the big scything talons, and crushing claws). Then I use these K&J Magnetics - Products for the smaller limbs and guns. Be sure to fill the inside of the body of the carnie with epoxy, so when you drill you've got something to drill against. It's very easy to drill right through the body.
Farseer Faolain of Craftworld Tuathana
Overlord of Hive Fleet Shoggoth
See my projects and tutorials at: http://awakeningynnead.blogspot.com