I've built a couple of smitty sleds over the years. Makes a huge difference pulling in snow.
A couple of tips selecting skis. Downhill skis are better than cross country. The downhill are wider and float better. The cross country skis have a more pronounced hump which makes it harder to level the sled structure. They'll also sink deeper in the snow or slush making for a harder pull. Still, cross country would be better than nothing.
Try and get a ski length that'll fit in your vehicle. I go just a bit longer than I need to fit under my toboggan. The length is usually printed right on the ski. The longer the ski the harder to turn and manouver in the snow.
Here's a link for sizing.
https://skiisandbiikes.com/blogs/ski-gu ... ngth-chartDownhill skis also have a hump in the middle. If you cut off longer skis, it'll move the hump towards the rear making it a little more challenging to level your toboggan.
You want skis with a plastic bottom, if possible. Pull better and much more durable than wood.
Skis are laminated construction and will eventually delaminate at a cut, crack or hole. I seal all of these with epoxy for longer life.
Sources for skis are Kijiji, Facebook buy and sell, yard sales, or second hand stores. Don't pay too much. Lot's of people just want them gone.
As for the structure, I used wood. Easy to work with and I had enough scraps laying around. I used bungees and eyes to tie the toboggan to the sled.
I found that if you make your sled joints too snug the wood will swell in the wet and the sled won't fit together. I used super magnets from Lee Valley to hold the joints together. They have a screw hole in the middle and I countersnunk them into the joint. Works real well. I believed I used the 1" on a 2x4. Maybe 3/4".
https://www.youtube.com/watch?v=OCXKm3_ ... =TheDewarshttps://www.leevalley.com/en-ca/shop/ha ... em=99K3325Good luck with your project.