A close-up of the area of the cam affected. Photo: DMM International
Llanberis-based climbing gear manufacturer DMM has warned climbers to stop using one of its cams that could develop cracks in its metal.
The recall notice only concerns size-six Dragon camming devices made between 28 April and the 30 June this year. It has identified 604 of the units that may be on sale or in use, which are affected by defective raw material.
Climbers are advised to stop using the cams in question and return them to where they were bought or to DMM for an exchange or credit. The company stresses no other size of Dragon cams are affected.
A statement by the company said: “The raw material involved is used to make the aluminium axle boss on the Dragon Cam in size six. DMM International has discovered that the components made out of this defective material can develop cracks and that these cracks can grow and propagate with time. This could cause the units to fail below their rated strength.
“We would also ask that any affected Dragon Cam 6 be returned to the point of purchase or to DMM International so that it can be replaced or credited. We predict we will have replacement units available for despatch by the middle of September. We fully understand that customers may not wish to wait this long and we will honour all requests for credit. If you would like a credit please return the Dragon 6 via the retail outlet where it was bought.”
DMM explained how the fault came to light: “On Tuesday 20 July, DMM International received a phone call from a retailer in the UK. The retailer had received a Dragon Cam 6 from a customer which had a severe crack in the axle boss.
“On receiving a photograph of the cracked axle boss we immediately started an internal investigation looking at possible causes for how the crack had occurred. We looked at all aspects of the product: material, design and processes.
“The aluminium axle boss on the Dragon 6 is a unique component that is CNCed from 50mm 7075-T6 aluminium bar. DMM only use 50mm bar for this unique product component.
“We have made 1,148 size-six Dragons to date. The axle bosses on these cams have been made from two separate deliveries of 50mm bar. The axle bosses made from the initial delivery of bar are structurally sound, do not develop cracks and are built to our normal high standards.
“However it seems that the most recent delivery of 50mm bar contains sections of bar that have an irregular grain structure and irregular grain boundaries. It is these serious internal grain irregularities that are causing cracks to appear and grow over time. We are currently not certain what proportion of the bar that was delivered is defective, but the raw material, all components made from it and all finished units have been isolated and quarantined. Samples of the bar have gone for independent analysis and we are talking to the mill that supplied the bar about the material.”
Details of the serial numbers of the cams affected by the recall are on the DMM website.
The Dragon is a dual-axle spring-loaded cam used by jamming into rock cracks as protection when climbing and, like all climbing protection, its function is critical in saving climbers from injury and death in the event of a fall.
