I love shaving horses and have made a few over the years. I love there simplicity and yet they are a highly efficient and usable tool, or as some of mine turn out to be, a work bench. In essence a shave horse is a quick release vice that you sit on, the cutting tool that is used with it is the drawknife.
Most of the time I like to work high, I have spent years on shaving horses that are to low for me and have suffered from shoulder and back ache.
The above photo was taken about 6 years ago, I still use it, but it is to low, especially for detailed work.
Made last year for a show where I only had a small space, designed for making fan birds on, hence the vice for holding the wood while I rive the feathers out.
A beast made from, ash, oak, Douglas fir and western red cedar. I have never finished it, but use it all the time in my workshop. The great thing about it is that is adjustable in almost every way. I was going to make a detachable chopping block that fits over the leg at the end. The dumb head is not fixed in any way and adjusts easily up and down, it wedges into place and a quick tap releases it so that it can be moved.
My most recent horse inspired by Ralph ( For Woodness sake), I first saw it on the paleoplant forum and then on the Bodgers forum. The seat is quickly adjustable up and down depending on what is being shaved. The dumbhead is easily adjustable, and apart from one piece, the horse was made using hand tools only. The seat was hewn from a large log of aspen and fixed using oak pegs into the seat supports.
These horses, on the whole, are for spoon making and fan birds, I can happily make chair legs and the likes on them, but some people may prefer something a bit more substantial.
I soon added a tool tray, not really a tray but a plank with holes drilled in it to hold:- chisels, axe, knife, drawknife and saws. This plank is held up with a peg near the seat and a small branch that comes out of the leg.
You may have also noticed that the red cedar block that I have put under the dumbhead does not come all the way to the end of the branch, this is because I like a little ledge to rest the fan birds on when carving the birds head or spoons with a knife.