CMC Rescue Rack
I acquired this rack from CMC in 2007.
The rack frame is made from 9.6 mm. stainless steel. The frame is 352 mm. high and has a 32 mm. internal width. The open leg is 210 mm. long above the lock nut. The welded eye has a teardrop shape and is 26.4 mm. wide internally. The lower portion of the rack looks like it was sandblasted after welding.
The rack has six black hard-anodized aluminum brake bars.All six bars have a 12.6 mm. central hole extending the length of the bar. The first 14 mm. of the holes on the fixed-frame side are enlarged to 18.5 mm. This allows moving the bars so that they pivot on the fixed side of the frame.
The top bar is a 25.4 mm. diameter, 89 mm. long hyperbar. The hyperbar is a solid 4.8 mm. stainless steel pin set 25 mm. from the rack frame. The pin is press fit into a blind hole drilled in the top of the bar.The pin extends 21.7 mm. above the top of the bar. The closure slot is angled to latch the bar.
The second bar is also 25.4 mm. in diameter. It has a straight slot. The top two bars have single precut rope grooves. The remaining bars are 22.3 mm. diameter bars with angled slots and no grooves. All six bars are offset so that the bar centerline is roughly tangent to the circumference of the frame.
The unloaded side of the top bar is marked with "CMC Rescue Rack," "MEETS NFPA 1983(06ED.)," "LOT No. 4104,", the Underwriters Laboratories Classified seal, and "5F04." The unloaded side of the second bar is marked with "Ø9.5-11.5mm, L 13.5 kN MBS" and "Ø11.5-13mm, G 13.5 kN MBS."
This rack is very well made. The hard anodizing should limit break bar wear when used on clean ropes. The central holes lighten the rack, but one should be sure to replace the brake bars before they wear through to the hole. The enlarged hole at the one end is a nice way to modify the bars so that they will pass over the top of the rack and pivot on the fixed side of the frame, where they belong. At the same time, this saves weight in the bars. The top two bars are larger than the others, showing that CMC recognizes that these bars heat more than the others.
This rack's weight is about average for J-frame racks, meaning that it is light for a full-sized rack. The axial holes in the brake bars provide significant weight savings. Eliminating the hyperbar would save some weight without sacrificing any utility in caving environments. Some rescuers like the hyperbars more than saving weight, it's a personal decision.
I would have made the free end of the frame 30 to 40 mm longer to allow more bar motion for reducing friction on longer drops.
The rope guides are a nice touch. The one on the second bar is in exactly the right place. The one on the top bar works fine where it is, but I would have moved it down about 30 to 45° to where the main wear will occur.
In the strength markings on the top bar, "L" means "Light Use" and "G" means "General Use." I suspect that the strengths listed involve rope failure since the rack probably isn't stupid enough to become weaker when used on thin ropes.
Overall, I think this is an excellent rack, so I give it a
star.
JRack1028.html/070318
©2007, Gary D. Storrick