All of them now, Define "hard"? it does/can be fairly physical. Heres some pics of the start of a "step by step" Ive been working on.
http://montanafreetrappers.net/6.html Im starting three more elk this eve.....
i would definaly say start small, something along the lines of a coon badger yote, mink squirlls, ect and learn hair on first not much differant but a few less steps, make a few then start on true leathers hair off ect.
ask around your local hunting population and gather some deer hides, you might be able to "scavange" some local road kills for hides, check with your warden and see....
Mat richards deerskins to buckskins series is pretty good esp the dvd over the book, but the book has a lot of recipies that are not covered in the dvd, another great source is home tanning simplfied by kathy kellog, a lot of great beginer recipies there as well and it also covers just about every type of fur/leather there is from sheep to snakes
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