David: I have attached another video showing a Hunslet rake and a 201 with 6 Mk3’s using the helix. Using the helix demands having all the factors right, a Diesel Locomotive, carriages with good wheels, good couplings (I can see why Anthony uses Kedee's resulting in every coupling being the same and at the same height). Speed up the helix is something which I need to prefect, too slow and the Loco can lose traction, to fast and you have the risk of derailing.
Josefstadt: When I was building the helix I used a Jeep and it pulled 3 carriages up the helix. It is DC and has yet to be converted to DCC so I have not been able to try it out again. However the Experts would suggest helix’s are not for Steam Locomotives.