Front	Rear

Left	Right	Open for Rigging

Technical Details

I acquired this CMI Lock Pulley from CMI in 2023.

My CMI Lock Pulley is 77 mm. long, 135 mm. wide, 51 mm. high, and weighs 332 g. The rope channel is 18 mm. wide. The cam radius increases from 41 to 57 mm. over an angle of 42°, giving a 25° cam angle. The tooth pattern is (4.3)^5(4).

This ascender is milled from the same shape extrusion as the CMI UltrAscender. The cam safety is similar to the one on my Modified CMI UltrAscenders. CMI attached a pulley assembly to the back of the ascender. The sheave is 38 mm. in diameter with a 13 mm. wide, 5.6 mm. deep U-shaped rope groove.

Comments

The Lock Pulley is not a Hauling Pulley per se, nor does it function well when used as one in the traditional sense.

I showed CMI my modified safety design in 2017. Now that they are using it on something, I hope that they make it available on the UltrAscenders. CMI1 describes it as follows:

Never rappel again without a Lock Pulley. When using a hook adjustable positioning lanyard assembly to rappel down it can be very difficult to pull yourself up to your original position. Using Lock Pulley you can easily and quickly hoist yourself up with ease. Lock Pulley features a cam that locks on to your rope to ensure you don’t slide down while using the attached pulley to climb back up. The open ended design can attach quickly and easily to your rope at any point, sliding up easily without the need to release the cam from the rope and allowing one-handed operation. Lock Pulley makes it easy for any climber to lift themselves to their original position after rappelling down, no matter where they are hanging from.

This implies that the Lock Pulley is designed for industrial uses that are outside of my normal needs. I'll leave its evaluation to the RATs.

1 Retrieved 2023-03-05 from https://cmigearusa.com/collections/frontpage-new-products/products/lock-pulley.