[roadranger]

Fred, that trailer is great! You ought to market that one!

Couple/three things;

One of the advantages of side dumps is that you can dump them while moving, to windrow the material. Like when laying down road base gravel. You spread it along so that a motor grader can work on it easier than a big pile.

I watched the 2nd video, and saw the difference between models and real world.
One thing you NEVER do in a side dump is dump them without the tractor being straight in line with the trailer - NOT jacked around to one side. The 5th wheel hinge will pivot with the weight transfer when you dump, and roll the whole rig over.

When dumping large boulders or rip-rap, you've got to control the dump slowly so that the boulders don't all spill out at once, and tip you over. Or pile up and smash back into the wheels and fenders. You drop some on the ground first, then drop the rest across the top of them and out away from the trailer. Looks like you've got real good control of the dump action on your trailer.

Well done!