I'll see if I can find a few pictures, if not I'll take a few next winter, and some SWT videos as well.
Ok I found a few pictures of our sleds.
But I only have one picture of our wood hauling sleigh, and not a very good one.
First you can see my brother working at skinning a log, as we were building a small porch for the cabin. The sleigh looks smaller than it really is. As I said, it is a 4 skis design, and most of the time we have this plywood box on top of it to carry logs. The box is 10ft long. The front skis are regular snowmobile metal skis with leaf suspension from the '70s era. The rear skis came from a old Ski-Boose, which had much longer skis, like 4ft long. Crossed chains links the front and rear skis and allow the sleigh to turn pretty tight. We can adjust the length of the chains for longer logs when we don't use the box. We use automotive style ball and coupler, and the tow bar is attached right at the tip of the front skis so the front end doesn't get caught if we hit a stump or something, the angle in he tow bar makes it slide away.
Next is our 'all-purpose" sleigh. We use it for pretty much anything, carry our stuff, ride around, haul water and wood.
Note that the tow bar is attached to the sleigh almost near the center of it. This allows the sleigh total freedom to ride the bumps without pulling up and down on the rear of the snowmobile, so you don't really feel it when towing.
It is mostly made of maple and oak that was steamed and bent. It has metal reinforcements where needed (all painted blue), the bottom is a 3/8" plywood, and we have a removable "seat" we can put in to carry a passenger (not shown).
Finally our 3rd sleigh is the one we use in the spring during the maple season. You can see it with the 45gal plastic drum we use to collect the maple sap.
Made of steamed and bent oak and maple, the one is very sturdy, and somewhat heavy for it's size. It has this little box in front where we carry pails, tools, etc. We also have a larger plywood box that we can install instead of the plastic drum, so we can use the sleigh to carry wood or whatever. The runners are slightly bent upward at the rear also, to make it easier to back it up. Sometimes in the spring the snow is bad, the sleigh gets heavy when the drum is full, so we need the ability to back up easily in case we get stuck.
Like I said, quite often at the end of the maple season there isn't much snow left, and there is a lot of mud, rocks and gravel in the trail. We needed the sleigh to withstand this, so the whole underside and runners are capped with a sheet of stainless steel.
Carl