Arbtalk.co.uk | Discussion Forum for Arborists

I have been experimenting with this device. It is essentially a modified roller chain, that acts as a collapsing compact rack, that is engaged by the integral eye to eye hitch when weighted. It has rollers where the climbing line enters and exits the rack and so acts like a hitch tender pulley when tending slack. I have a demo vid on youtube entitled "bulldog pulley/rack"

Interesting idea. That is the mankyist bit of hitch cord that i have seen in a while, that you are using in the vid.

Any idea of the breaking strain of the pully rack ?

Yea, the yellow hitch cord is glow in the dark too : )

The ANSI roller chain links are rated at 14,000 + lbs.

An online arborist sparked this idea also which works well for pulling the pulley rack up the climbing line on ascent, and for using it on a doubled line as well. He is giving it a try today.

Dammit, I had a vision of inventing that thing and it already exists! Looks intriguing, I'll check out the video

Here is Tony's review of the pulley/rack.

Tony you may want to try this shorter configuration, Just remove the bottom link, and two connecting side plates, and move the 5/8" roller to where the 7/16" roller now resides, This will leave you with 2 5/8" rollers on the same side as the hitch climber pulley.
It does not take as much friction this way below the hitch, as there is less roller chain length, but when releasing the hitch on a doubled rope it allows the hitch to bear a little more weigh rather than practically nothing at all. On a single line you have to work a little more to release the hitch but that is not nessecarily a bad thing.

Gordon

This all steel pulley/rack/hitch works well. the top rigid OAR arm added to the pulley rack makes a slight bend in the rope, which acts like a spring to engage the entire device. When weighted, the top arm swivels up and binds on the rope, sharing the friction with the rack below. It has little sit back, and tends slack nicely.

Here is a video of the hitchless pulley rack in action.

thought I would post this video of the hitchless pulley rack, which better explains how to install and use the device.

interesting... i'll be keeping my eye on developments