Grind the flax in either a coffee grinder, or a high-powered blender. Stir in the salt, add water and stir. Please note that ground flax is highly absorptive and will stiffen up quickly, so you may have to add more water. Spread the mixture onto dehydrator trays with the Teflex sheet. Score the batter into cracker sized pieces. Dehydrate at 135 degrees for two hours, then flip the crackers off the Teflex sheets directly onto the dehydrator mesh trays. Continue to dehydrate for at least 12 hours at 115 degrees, more if you like them extra crispy.