You might try several nuts from each tree. I found that some trees are much easier to shell than others. As a form of efficiency, I would focus on the trees with the biggest nuts, and those that are the easiest to shell.
Couldn't find the video of the method i use to process the nuts (before shelling).
I'll try and describe it. I don't know of an black walnuts here in Montana to video the process:
I peel the husks off when they are still green (but soft enough to dent with your thumb), if possible. I've heard that the black stain from the rotting husk will leach into the nut and change the flavor. I mount a hacksaw blade upside down in a vise. This blade is sharp enough to cut through the husk easily, but not really sharp enough to get cut on. I spin the nut on the blade to create two hemispheres in the husk, which then twist easily off the nut. I throw the nuts into a 5 gallon bucket that is 3/4 full of water. I use a homemade paint mixing paddle that i mount in a drill. It spins all of the nuts around and as they bang against each other, they rub the pulp off of each other. Any pulp should not be attached at this point and will fall off as they dry. If there is a lot in your drying pile, you might try a second quick rinse. Then i dump them out and dry them for a couple of weeks before putting in storage, or eating. I put them some where with good airflow, but out of the sun. If they are stacked too deep they won't dry very well. Every couple of days, i would stir the pile a little.
I never used gloves, and it takes about two weeks for the stained skin to be replaced. (having stained hands starts lots good conversations about local food)
The master cracker is the best cracker for black walnuts, it is American made and has more adjustments then the rest. I have a Hunts cracker and the Master cracker my friends have works better. If you don't have a cracker around you can use a shop vise, it works pretty good.
We have an Amish made cracker that came from Lehman's Hardware many years ago. We've found a couple of tricks to cracking black walnuts and hickory nuts.
1. Don't crack until the nuts are over 1 year old. The nuts keep fine in the shell in a cool dry place and will crack easier in their second year (the nutmeats shrink ever so slightly from the shell). In the wild, nuts will often not germinate until their second year so the nut is well suited for extended storage.
2. Sift out the fines with an 1/8" screen. Sort cracked nuts into 3 piles: nutmeats, empty shells, and shells with nut pieces left to remove. You need good lighting to make quick work of this task. We dump the cracked nuts onto a table and slide the pieces into the appropriate pile. This is faster than trying to pick up the pieces. No matter what method you use to crack the shells, sorting will be the slowest part of the process.
3. Don't recrack the large shell fragments. Use a wire cutting snips instead to make a few strategic cuts in the shell to release the nut meats without crushing or digging at them with a nut pick.
Black walnuts are quick and easy compared to hickory in terms of volume of nuts shelled out per time spent on the task.
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