Front View: Closed	Rear View: Closed
Front View: Open for Rigging	Rear View: Open for Rigging

Technical Details

I acquired this ascender from Artyom Babin (Артём Бабин) in 2024

This ascender is 181 mm. tall, 93 mm. wide, 31 mm. thick, and weighs 216 g. The shell is a tall irregular shaped stamping made from 3.9 mm. aluminum alloy sheet metal. A 16 mm. rope channel is formed in the upper portion of one side and a smaller cam channel lies opposite the first. A hole drilled through both sides of the cam channel accepts a 6 mm. semi-tubular rivet. The cam and cam spring are mounted on this rivet. The cam axle is centered 51 mm. from the inside of the rope channel.

The handle is molded from red plastic. The handle front side of the handle does not extend as far up the front strap as the rear does. This is to provide cam clearance. A 14.7 mm. sling attachment hole is punched below the handle opening. A 14.3 mm. hole through both sides of the rope channel provides an attachment point just above the cam.

The cam is milled from steel plate and then plated. The cam radius, measured from the axle axis, increases from 39 to 54 mm. over an angle of 39°, giving a 25° cam angle. The teeth are pyramidal, formed by criss-crossing v-shaped cuts. The tooth pattern is (3.4)(5.4)^12(3). There are two v-shaped notches on the rear side of the cam and one on the front. These appear to be for mud relief.

A spring-loaded manual safety bar is mounted on the bottom of the cam with a steel semi-tubular rivet. The normal action of the spring holds the safety against the cam. When the cam is opened, the shell interferes with the safety bar, thus preventing opening the cam. If the safety bar is moved away from the cam (opposing the spring), it will clear the shell and the cam will open. At full open the safety can be released and the spring will hold the safety against the back of the shell. This provides a means of locking the cam open. A knob on the safety bar assists in operating the safety mechanism.

There are no markings on this ascender.

Comments

This ascender is very well made for its time.

The cam is unusual. Steel cams wear better than aluminum. Milling avoids the complexity and expense of casting steel (or stainless steel) for low-volume production. The plating is effective, as there is no rust on this ascender's cam

I find opening the ascender with the right hand to be reasonably easy, but getting the safety to latch afterward is difficult. Opening with the opposite hand is far more difficult.

History

We have no information on this ascender's history other than it was made in the USSR in the 1970s or 1980s.