the wall walking rig #2 –
The harness used came from from the same company that made the flying rig for the broadway play Peter Pan. It holds a wire on either side (or both). A simple push of the pin and u are free or connected.
I think the company was called Z rigs (or something similar). The wire used was black air craft cable. I built it all to hold 500 pounds just to be sure.
-Instead of using a barndoor, use a small metal rod about 12 inches long. Weld the two wheel brackes to this bar drill a hole through the bar or weld a metal ring to hold the cable.
The track is not too expensive. the don't look like they support much, but if you have a barn, you know those suckers can hold up a lot of weight. The wire is not a bad expense either. The harness put us back about $5,000. But it was worth it for safety.
Hope that helps.
If any other haunters are interested in the more advanced track rig and willing to make one, send me an email.