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Hulling walnuts, removing the husk, can be a difficult and messy task. The indelible dye from the husk stains hands, clothes, tools and work surfaces. If you are working with dry nuts, the husk can be removed by applying pressure to the ends of the nut. This can be done by pounding side to side with a hammer, of course while wearing safety glasses.A cement mixer just to get some nuts? Sounds like Thorny Guy needs a new tool!
The husks can also be softened in a container filled with a slurry of three parts nuts to one part water and a handful of gravel. Stir the mixture vigorously. It may take more than one attempt to completely remove the husks.
If you are hulling a large quantity of nuts, the slurry can be used in a small portable cement mixer. An old-fashioned corn sheller will also be useful in hulling black walnuts.