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Recall on the Dragon Camming Device Size 6

ajfclark

24-Jul-2010
7:41:05 AM

Not a good start

From http://www.dmmclimbing.com/news.asp?ngroup=2&nid=315 :

Recall on the Dragon Camming Device Size 6 23/7/2010

DMM International has identified a raw material problem that may affect the strength on certain models of the Dragon Cam in size 6 (Product Code A7056A).

This recall only involves the Dragon Cam in size 6 and no other sizes of Dragon Cam are involved.

The problem originates from a structural defect in a raw material that is uniquely used to make a single component on the size 6 Dragon.

The raw material involved is used to make the aluminium axle boss on the Dragon Cam in size 6. 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.

More information is available here.
The more info link goes here http://www.dmmclimbing.com/dragonrecall.asp but returns a 500 error at the moment.

ajfclark

25-Jul-2010
9:27:06 AM

I found some more details in this image:

turtlespit

26-Jul-2010
7:04:33 PM

Not great news, but at least they seem to have been upfront and timely with the recall.

Hopefully they'll handle the replacement units quickly.

Chockstone Moderator

26-Jul-2010
8:53:08 PM

[Second thread on the same topic is now deleted, with the post it contained copied to here, by Chockstone Moderator].

On 26/07/2010 desk monkey wrote:
>I just spotted this, if you’ve got some shiny new Dragons then you’d better
>check the codes
>
>http://www.ukclimbing.com/gear/news.php?id=2905
>

ajfclark

27-Jul-2010
10:27:27 AM

Speaking of duplication, does anyone else think it might be useful to keep a central store of recalls with just a collection of links to threads about recalled products?

IdratherbeclimbingM9

27-Jul-2010
12:19:56 PM

On 27/07/2010 ajfclark wrote:
>Speaking of duplication, does anyone else think it might be useful to keep
>a central store of recalls with just a collection of links to threads about
>recalled products?

Not a bad idea.
~> Possibly could be put on the Links page under a 'Recalled gear' heading near the 'Gear' links?
... ~> but then again, may be too obscure/lost there??

For historical reasons it would be easy to look them up if all the links are found in one place, but for practical needs maybe the issue is adequately dealt with by having a topical thread such as this one at the time of recall; ... as once the recall has stood for a while then the deed has been done?

Maybe as top of that page suggests, contact Chockstone author by the email link with the suggestion for inclusion / link to this thread?

ajfclark

27-Jul-2010
12:56:42 PM

I just think a sticky thread called "Recalls" would jump out at people as something they should read if it came up green. I mean, DeskMonkey missed my post about this and that was only a few days later...

ajfclark

27-Jul-2010
12:58:03 PM

For those that don't click through to the ukclimbing link, here's the new info from there:
Addendum – Full Background on the Dragon 6 Recall

On Tuesday the 20th 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 aluminum axle boss on the Dragon 6 is a unique component that is CNCed from 50mm 7075-T6 aluminum bar. DMM only use 50mm bar for this unique product component.

We have made 1148 size 6 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.

There are 304 size 6 Dragons with bosses made from the second batch of poor material in the market worldwide. We are however issuing a full recall of all 604 units that have been shipped from our warehouse in case of any cross-contamination of components and to avoid confusion amongst consumers.

We believe the mechanism that is causing the cracks to appear in the axle boss is as follows:

• The axle boss is machined from the defective 50mm aluminum bar and are then rumbled, heat treated and anodised. These bosses can contain serious grain irregularities and irregular grain boundaries, but visually seem perfect. Thus they pass pre-assembly inspection and go into preassembly stores. The axle bosses are tested by trying to pull them apart with the axle rods inserted – all bosses tested have made over 22kN.

• The cam stem is then press fitted into the axle boss – at this time and from now on the boss is under stress as the stem is a compression fit.

• If the internal structure of the aluminum material used to make the axle boss contains areas of weakness then it may be unable to resist the expansion forces generated by the stem being in compression and cracks can gradually initiate. These cracks are initially microscopic and not visible, but then over time grow and propagate until they are easily visible.

• Every safety critical product we manufacture is 100% inspected after final assembly, however because this problem develops over a period of time the units appeared perfect and were passed into the finished goods warehouse. The completed sub-assemblies were tested to failure at over 16kN

• We are still investigating the factors and timelines involved in cracking process, but it seems to take a period of between 3-4 weeks for cracks become visible.

We have checked stock sitting in the WH and can see very small cracks have started to appear in about 15% of units that are about 1 month old. Units with very small cracks like this are still making over 14kn in destruction testing, however we anticipate that units with larger cracks will break well below their rated strength.

We have received back the unit with the full crack in the boss and will destruction test this once we have concluded the non-destructive testing.

We will, of course, continue to investigate this further and implement all and any procedures necessary to stop this type of incident happening again in the future.

gfdonc

27-Jul-2010
1:30:55 PM

Pretty good response - I applaud DMM for the follow-up, this issue is only a week old!

FWIW I used one of these cams on the weekend, first impressions were good. (It wasn't a size 6).

Desk Monkey

27-Jul-2010
7:23:54 PM

On 27/07/2010 ajfclark wrote:
>I just think a sticky thread called "Recalls" would jump out at people
>as something they should read if it came up green. I mean, DeskMonkey
>missed my post about this and that was only a few days later...

Yup, I totally missed the first thread and thought it was an important thing to post.

Mike Bee

27-Jul-2010
11:23:36 PM

Some of the recalled #6 Dragons have been shipped to Australia.
If you have purchased one, (or work in a shop selling them), check the serial number carefully.

ajfclark

15-Oct-2010
8:00:32 AM

They've redesigned the faulty part, it's now hot forged instead of being CNC milled: http://www.dmmclimbing.com/news.asp?ngroup=2&nid=332

DMM is pleased to announce that the issue affecting some size 6 Dragon Cams resulting in a recall notice has been resolved. A brand new replacement unit will be going out this week to everyone who returned their size 6 Dragon cams.

The units have been modified by the previously CNC aluminium axle boss / termination being replaced by a hot forged component. Explaining the change, DMM Technical Director, Fred Hall, said: "The change to a hot forging process has resolved the issue of predictability in manufacturing the axle block."

"Modified units will instantly be recognisable as the new termination is very different in appearance to the original. From a manufacturing efficiency point of view it is logical for us to do the same for sizes 4 and 5 in the future so we have a suite of components."

Since the Dragon Cam sizes 1, 2 and 3 are manufactured from 316 stainless steel they are totally unaffected. DMM Brand Manager, Chris Rowlands, said: "Once again I'd like to thank all our customers and retailers who were affected by the recall for their patience and understanding."

And they've recalled all of the old model:

http://www.dmmclimbing.com/news.asp?ngroup=2&nid=333

The original recall notice was issued on 23/07/10, and since then we have received the majority of the Dragons back either from Individuals, Retailers or Distributors. However we wish to speed up the process, and also do everything possible to ensure we get 100% of the affected units accounted for as soon as possible. The response from all our customers to date has been very supportive and helpful in passing on the information in order to try to contact the largest number of end users as possible. Thank you to everybody who has helped us with this process so far.

We are therefore repeating our request for anybody in possession of a DMM Dragon Cam size six to either return it direct to us for a replacement unit, or to the point of sale if you require a credit. Customers from outside the UK should return the units to the point of sale, or the Distributor. Please note that only customers based in the UK should use the online form to arrange for a replacement.

For completeness if for any reason you are in a posession of a Dragon size six with a different serial number to those previously posted please also discontinue use and return to us as per the instructions above. If the details listed here and in the original recall notice are unclear please contact us direct:

Phone +44 (0)1286 872222 or email post@dmmwales.com

We are confident that we will be in a position to replace all the recalled units by early October, and free stock of the size six will be available shortly after. Again we offer our apologies to all our customers for any inconveniences caused by this recall, and we are continuing to work hard to rectify the matter.

damon

9-Nov-2010
7:08:04 PM

Well finally got one of these puppies delivered and check out the condition it came in!
Clip is missing from the side of the unit with the cam detached.
Not Happy DMM.

http://www.facebook.com/photo.php?fbid=452554502342&set=a.452554497342.246477.550622342

dave

9-Nov-2010
7:26:42 PM

Thats disgraceful. Good that the packaging directly above where the cam lobe should be says 'Maximum Strength'!

ajfclark

30-Jan-2011
5:27:16 PM

Brief update from DMM: http://www.dmmclimbing.com/news.asp?ngroup=2&nid=358

There are 15 messages in this topic.