One of the easiest ways to build something like that is go look at a commercially built unit and get their best ideas then add your own touches to suit you. I bought a Tractor Supply 35 ton splitter this winter after using my home made 3pt tractor splitter that I made probably 23 or 24 years ago (it kept being borrowed so much it was never around and I thought, you know, twenty some years of service ought to be good enough, I'm just going to get me a new one). Boy that new TSC splitter works GOOD. Doesn't use much gas, splits anything I ever need to split. Check one out at the TSC store and build like it because it works good. Two things are cheesy on it. The little wheels with ball bearings are just waiting to go out and the tongue is flimsy but adequate. Someday those two parts will get my special touch as they fail, but the splitter part works awesome. Whatever you do, make it so it will split in the vertical position. I did that with the 3pt unit I built long ago before vertical splitters were cool and it is the only way to go as far as I am concerned (the TSC will split in either horizontal or vertical). With vertical splitting I can roll up a 2 or 3 foot diameter piece of wood, tip it on to the splitting foot, and split pieces of wood no way I could ever lift. With a horizontal splitter you pick the wood up and split it once and it falls on the ground, you pick the wood up to split it again and it falls on the ground. You have to pick the wood up every time you make a split. With a vertical splitter big logs just need to be rotated to the next splitting position. It is the only way to go if you split anything of size at all.

John