Version A	Version B

Overview

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Version A
(#718)

Front View: Closed

Open for Rigging

Top View

Technical Details

The Flash Bar is a single roller mounted on a rod frame. The rod has one 1/4" roller side plates pressed and pinned to it. Each end of the rod is drilled to accept a 1/8" by 2" stainless steel split spring pin that serves as a harness attachment point.

The thick side plate has a 5/16" stainless steel rod pressed into it to serve as the pulley axle. It is pinned in place to prevent rotation. The 0.8" diameter nylon pulley and 1/8" thick aluminum side plate are held in place by a 1/8" by 3/4" stainless steel roll pin. The knob is turned aluminum, and is spring-loaded to engage two holes in the swinging side plate. When engaged, the side plate is held in the closed position. The knob can be pulled out to free the side plate, and when the side plate is swung, it holds the knob in the withdrawn position.

A small hole in the fixed side plate can be used to wire a pulley for double-bungee rigs.

I believe that all aluminum parts are 7075-T6, but this is from memory of a conversation held a couple years ago, so I may be mistaken.

Comments

The Flash Bar was designed by Benjamin von Cramon. He was trying to make an exceptionally light chest roller that still had a full-width bar, and he succeeded. The Flash Bar weighs only 36 grams more than a Simmons Roller, but the bar keeps the roller much closer to the chest, which improves climbing efficiency.

The down side of this device is the harness mounting. It takes some care to sew a harness that holds the flash bar properly, but this can be done (and commercial harnesses were available), so one shouldn't have too much trouble. Look at the Version B pictures for an example. Just make sure that the harness is designed so that puts the load on the main rod, not the small roll pins. They are for positioning only.

The Flash bar is good design, well executed.

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Version B
(#722)

Front View: Closed

Top View

Open for Rigging

Front View: Sewn to Harness

Technical Details

I acquired my double rope Flash Bar from Inner Mountain Outfitters in 1999. I acquired a second one from Bill Liebman at the 2017 Old Timer’s Reunion.

My double rope Flash Bar is 51 mm. long, 215 mm. wide, and 54 mm. high. The first one I acquired is attached to a commercial harness, so I'm not able to weigh it properly. The second one was missing the 1/8" by 2" stainless steel split spring pins. I added the proper pins, and it now weighs 150 g.

This Flash Bar is a double channel chest box consisting of a rod frame /w roll pins, a double roller, and side entry, pull-knob activated gates. Operation and dimensions are slimilar to the single rope flash bar.

There are no markings on my Flash Bars.

Comments

This is a double-roped version designed for Mitchell System climbers. Notice how the Flash Bar is sewn to the harness, especially how it puts the load on the main rod, not the small spring pins.

Some of my female caving friends have told me that this was the most comfortable chest box that they had tried.

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