My current layout consists of two large loops with one at 'ground' level and the other approx 7 inches above it. I want to connect the two loops using a helix that I will build by breaking through the wall into the furnace room. Look at the pic attached that shows the levels of the tracks but note the 'break through' will be behind the breaker.
What grade can I safely use for this creation? I was targeting 2% but run some long coal trains that pull 10-12 die cast K-Line hoppers and want to be sure my MTH locos will handle the load.
I calculate that grade (2%) as needing 350 inches of track to work for 7 inches so almost 30 feet.
If I do a helix with two loops each would be 15 feet in circumference for a diameter of 5 feet. Is my math right?
What radius would that yield as I have O54 now to allow everything to run smoothly?
Any other suggestions/advice besides forgetting the whole idea and just running two separate loops.