2 Answers

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One good thing is to do it in cooler weather, as it does attract many flies.  As with other hides, scrape, scrape, scrape the fat.  Salt will also dissolve fat, and you can store it between work sessions if rubbed with ample salt and rolled up.  The Alum method is a good one for tanning hides.  This can be purchased at some pharmacies, especially old fashion ones, not at strip mall types, however.  You may find good videos on You Tube to show the procedures, as a book can only tell you and you may miss technique.  It may be a good idea to start with a small animal hide first, if you have never done any before, it is better than ruining a full cow hide.  Good luck.