Yeah, the ties would be grooved about 1/4" to accept the rail. I was going to use a thick epoxy, like JB Weld, to hold the rail in the groove in addition to the friction. I think the composite board would be ok since its engineered to be outside in the sun. I'll do a few sections and leave them outside this summer to see how they react. I've seen a lot of homemade aluminum track, just no homemade stainless. Was just wondering if there was a reason for that.