Kong-Bonaiti

Technical details

I acquired this bobbin from Inner Mountain Outfitters in 1994.

The two side plates are made of 35 by 3.7 mm. aluminum. The lower ends of the side plates are bent to converge at the attachment point, which consists of a 13.5 mm. wide oval hole in each side plate. An 8 mm. post is attached to the top of the fixed (red) side plate, and two 35.5 mm. bollards are attached below. The blue side plate pivots on the lower bollard bolt to allow threading the rope. The bollards are turned aluminum with a milled slot to keep them from rotating on the fixed (red) side plate. The bollards are drilled and tapped then bolted to the fixed side plate with 7 mm. A2 bolts. Shoulder nuts lock the bollards in place and also retain the pivoting side plate. The pivoting side plate has a slot to allow clearing the upper nut and a second slot to engage the post. Both bollards have U-shaped grooves with about a 7 mm. radius. The bollards are not centered on the side plates. The upper one is offset about 7.5 mm. and the lower about 2.5 mm. The plastic gate safety is spring-loaded and riveted to the swinging side plate. Like many of Kong's plastic components, this one is phosphorescent.

The side plates are stamped with icons illustrating how the descender is threaded. Since the bobbins are off-center, there are two possible ways to rig the traditional bobbin "S." The blue side plate shows the normal rigging, and is stamped "LOW-SPEED" and "LENTO." The red side plate shows a faster rigging method. It is stamped "HIGH SPEED" and "VELOCE." The blue side plate is also stamped KONG_BONAITI," "ITALY," ,"<-.KG.2200->" and "ø rope mm 9-12." The bolt heads are marked "VIBO" and "A2.70."

Comments

Since both bollards have U-shaped grooves, this bobbin tends to be faster than the Petzl bobbins. The offset upper bobbin helps by increasing friction somewhat. I can't imagine someone my size using the high-speed rigging on a clean rope, let alone the "C" rigging some bobbin proponents suggest. The plastic gate will not cause corrosion like the metal Petzl gates will.

The bollard bolts are about 1.5 mm. too short to extend through the shoulder nuts, so I recommend checking them carefully before each use.