Horizontal is how I roll 99% of the time. Easier on my back lifting logs than bending over for verticle splits believe it or not. I'll flip mine verticle to split 2' dia. logs in half though. I've always been the "grunt", while dad ran the lever ... we were a great team. Now I run it solo .... and from the wrong side

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Hey.... I'm a lefty ... we adapt to tools ... or die trying

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