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DMM Revolvers seized. Anybody successfuly repaired them?

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daualset 29 Oct 2012
DMM revolvers must be some of the best gear I have ever owned...

I use them to reduce drag on trad routes but above all on the cruxes of sport routes. Falls are just that much smoother and the rope hardly gets any wear.

The thing is my Revolvers rarely last more than a year.

The rope rubs against the side of the carabiner next to the pulley (opposite the wirelock)and only comes into contact with half the pulley. After being used numerous times the pulley starts wearing down along it´s axis and develops play. Once this happens it normally seizes up and can no longer be used. This isn´t just because it no longer turns but often because the side of the pulley is exposed and is sharp enough to make one hesitant about using them.

I sent an email to dmm and they replied saying they sold no replacement parts and also asked what use they had seen during there lifetime. They were also kind enough to send me a user guide... I´m still waiting for a reply to my second email.

I was wondering if anybody on this forum has had any luck repairing them and if that is not the case maybe enough people would like to share their experiences with Revolvers and in this way we might be able to encourage them to sell a repair kit.

Here are some photos of my revolvers:

http://img338.imageshack.us/img338/84/photo1rd.jpg
http://imageshack.us/a/img525/3503/photo4jm.jpg
http://imageshack.us/a/img248/6759/photo3of.jpg
http://imageshack.us/a/img703/6910/photo2brv.jpg
http://imageshack.us/a/img543/6707/photo5yq.jpg

 biscuit 29 Oct 2012
In reply to daualset:

How old are they/what use have they had ?

To me the wear looks the same as the equivalent on a normal draw, it's just on the pulley instead of in the corner between the back bar and the bottom.

I guess they are made of the same materials as normal draws and will wear as quickly.

I take your point about the wear being on one side instead of totally on the pulley ( which i guess would negate the normal wear and tear in the corner ) but the wear is in the place where it normally would be on a draw as that is the strongest part. Maybe that's just how it has to be.

Have they lasted as long as a normal draw ? If so i reckon fair enough. If not i would be a bit miffed as well.

BTW how many do you have and have you won the lottery ?
 Ally Smith 29 Oct 2012
In reply to daualset: That's some pretty massive wear you're showing there.

My revolvers are 5+ years old and don't have anything wrong with them.

The photo background seems to show some gritty looking ground. If your rope is picking up that shit its not surprising you're wearing kit out quickly.

You could try washing your rope a bit more often and using a rope bag?
 AJM 29 Oct 2012
In reply to ally smith:

Ditto, not sure what I've been doing right to avoid that sort of wear!!!
daualset 29 Oct 2012
The revolvers are between two and one year old. I take good care of my gear and my ropes are always clean.

One is a beal tiger which has lasted me a good two years. I give a lot of credit to the revolvers for the rope lasting so long, and by far makes up for the extra quid they cost, or so I thought until they started wearing prematurely.

I sport climb at least twice a week and use the revolvers on places where I reckon I´ll fall and if there are any left I use them on the anchor to lower down (never for toproping). One of revolvers greatest assets is that the rope gets no wear whatsoever when you´re pulling yourself back up to the quickdraw after a fall.

I also use petzl spirits and wild country nitros and their wear is minimal compared with the revolvers
 jon 29 Oct 2012
In reply to daualset:

I've never used Revolvers so have no experience of them. That's a strange wear pattern. Why does it extend so far to one side (always the same side) of the roller? Is your rope really old/thick/furry? Does the rubber gizmo hold the krab in the wrong position on the sling? It looks that way on your photos, but I'd imagine once the krab was loaded it'd pull into the correct orientation. I'd love to hear DMM's explanation.
 Kevster 29 Oct 2012
In reply to daualset:

From memory, mine have a similar pattern of wear, they have yet to seize.

I use mine for trad and sport, they aren't unusually abused or over used. I guess 3 yrs old.

I only have 2 though.

Good luck, Kev
daualset 29 Oct 2012
I´ve used them with a 10mm beal tiger, a 9,7mm tendon and an 8,5mm edelweiss.
All pretty thin ropes.

The carabiners pictured are paired with petzl spirit slings. As you mention the carabiner looks as though it sit incorrectly but once loaded they move into the same position as they wood with any other sling
daualset 29 Oct 2012
Lots of my mates use revolvers and are also experiencing the same problems with a wide variety of slings. I´ll try and get them to post photos or at least send them to me so I can post them.
 jjclarke70 29 Oct 2012
In reply to daualset: It seems to me from the pics that the rubber petzl 'string' maybe holding the krab in slightly the wrong orientation meaning that the pulley wheel is not at the lowest point
 itsThere 29 Oct 2012
In reply to daualset: are you pulling the rope through with weight on them, i would make a gess at that causing the damage.
 wilkie14c 30 Oct 2012
In reply to itsThere: I'd agree, the wear is caused by the crab being loaded from falls, lowering off, resting and hauling yourself back up to crux moves. The force and weight on the roller being pushed sideways looks like the roller is wearing against the side of the crab. I think its fair to say that revolvers were really never designed for sport climbing but for the trad/winter climber to carry a couple for use on slings and stuff to reduce drag. Bet DMM never saw this sort of wear when they designed them, I'd be very surprised if they didn't want to examine these though.
Its only my view of it but this sort of wear wouldn't happen for years on trad use. I've 2 on 60cm slings that I use regularly and mine are 5 years old and there is no detectable wear to the rollers, I've just checked. The roller and side of the crab rubbing when used in a trad set up would never wear with no load to them but in sport, with 15 stone of climber loading that roller frequently I see the roller being pulled in one direction or another, only a mil either way, but the roller will comtact the crab and a huge amount of friction will be generated as its such a small surface area.
Only my view as I said though. Interesting thread.
 TobyA 30 Oct 2012
In reply to blanchie14c: My two revolvers are also I reckon 6+ years old and have no problems but I think I probably use mine only a tiny amount in comparison to the OP.

daualset - you say you sport climb with them a lot, particularly on cruxes - so I guess they're just getting very heavy wear? I have fallen onto mine but I think only a handful of times over those years, I normally use mine ice climbing and trad climbing.
 elsewhere 30 Oct 2012
Naturally they'll be fully rated as caribiners for load but the bearings aren't rated to rotate under that full load. Bearings rated to reduce rope drag & as a pulley only, lock up under higher load of a fall?
 thedatastream 30 Oct 2012
In reply to elsewhere:
> Naturally they'll be fully rated as caribiners for load but the bearings aren't rated to rotate under that full load. Bearings rated to reduce rope drag & as a pulley only, lock up under higher load of a fall?

I asked this question of DMM a while back and got a good reply - http://www.ukclimbing.com/forums/t.php?t=500875

"The pulley stops rotating at around 11.5kN. At this point the Revolver acts as a full strength carabiner..."

There is also some interesting discussion about the effectivness of the pulley further down the linked thread.
 AJM 30 Oct 2012
In reply to elsewhere:

A quick google suggests a number of websites like Needlesports and other online vendors saying the pulley still rotates under 11kn of load, which presumably has come from dmm although their website page on the revolver doesn't seem to mention it.

I use mine quite regularly on the bottom draw on sport routes to help give a more dynamic fall so the pulleys get loaded, albeit not by a full fall load, each time I then lower off.
 jimtitt 30 Oct 2012
In reply to daualset:
Surely dogging routes and using them as a lower-off is a bit outside of anyones realistic expectations for a product designed (and marketed) to reduce rope drag and as an emergency pulley?
And the chances of anyone selling repair kits for karabiners is nil one would think!
 elsewhere 30 Oct 2012
In reply to AJM & datastream:
11kN is a big number, that's pretty much the strength of a medium/large nut so in theory the pulley should lock up as often as a medium/large nut breaks (ie pretty much never).
 Fraser 30 Oct 2012
In reply to daualset:

I have a couple of Revolvers which get used very regularly, mostly on sport routes rather than trad. They also have the Petzl rubber band holders. I'd need to check but I'm pretty sure neither are displaying wear anywhere near as bad as yours are.

The other poster's comment about your rope posible pickig up bits of grit from the ground might be correct. Out of curiosity how worn are your regular crabs?

I'd agree with Jim above, there's simply no way anyone's going to sell repair parts for such a piece of kit.
 IainAM 30 Oct 2012
In reply to daualset:

The slings you are using are far too wide for the revolver, having the carabiner sitting at an angle like that isn't good and will repeatedly load the revolver in an off-centre position. Combined with how hard you work them it's not really surprising that they're getting damaged in the way your pictures show.

imho using them on every draw is overkill, good rope management should solve most drag issues trad or sport, and a bit of friction in the system helps your belayer, especially if you're working a sport route. For me using them falls into marginal gains territory, I've never had trouble on a route because I didn't have revolver draws.
My revolver's only ever been used on the first draw or where there's a big change in angle.
 Fraser 30 Oct 2012
In reply to daualset:

Looking again at the photos (at least the first few), it does seem like the rubber band is off-centre, which might encourage the crab sit sit slightly squint. When it's repeatedly loaded in such orientation, it's maybe unsurprising the wear is similarly eccentric.

The last photo however shows the rubber more centrally located, and the wear seems to be central. Perhaps this is the cause of the problem after all
 IainAM 30 Oct 2012
In reply to IainAM:

To clarify, the width of the spirit slings is too wide to sit in the narrow head on the revolver draw, the crab will inevitably rotate so the sling sits along the beam and loading will usually be off-centre. If you want to stop that use narrow slings with the revolvers, 11mm ones work with mine.
 jkarran 30 Oct 2012
In reply to daualset:

> I sport climb at least twice a week and use the revolvers on places where I reckon I´ll fall and if there are any left I use them on the anchor to lower down (never for toproping). One of revolvers greatest assets is that the rope gets no wear whatsoever when you´re pulling yourself back up to the quickdraw after a fall.

I think that (lowering) combined with a gritty environment is likely to be your problem. The notches in the krab body suggest your rope is more abrasive than you might think, Ally's suggestion of washing it then keeping it off the floor is a good one.

It's odd though, I don't take any real care of my kit and it doesn't suffer like this. Where do you climb?

jk
 jon 30 Oct 2012
In reply to daualset:

Thinking about this a bit more... You say that using one of these when working a route greatly reduces wear on your rope. Maybe this is true - but all that energy has to go somewhere, and in this case it's the karabiner/roller that's suffering. I'd also think that in repeatedly pulling yourself back up, you are probably pulling the rope at an angle some way off the centre of the roller. This could at first cause an uneven wear on the bearing/bush which could then lead to a permanent situation where the rope just wouldn't stay on the roller, and would automatically slip to the side, regardless of where that particular draw was being used. I'd say that maybe a good old fashioned large diameter krab would probably be a good compromise for sport climbing.

I've recently binned my old lightweight quick draws that were getting badly worn and bought a new set. I'm not going to use them for sport climbing - or at least not for routes that may need lots of working - and I've dug out a complete rack of old quick draws with big chunky krabs just for that.
 itsThere 30 Oct 2012
In reply to thedatastream: bearings dont last forever, maybe they could use harder bearings but then it may damage the axel. which might not be as useful since that could cause the roller to move and the rope could be pinched.
 Morgan Woods 30 Oct 2012
In reply to daualset: Can't comment specifically on the wear but when I have seen people use them for working routes they use one below the crux move AND on on the first bolt in order to make the fall softer...is this your approach?
 nniff 30 Oct 2012
In reply to daualset:

> I sport climb at least twice a week and use the revolvers on places where I reckon I´ll fall and if there are any left I use them on the anchor to lower down (never for toproping).


I think that statement sums it up - they are subjected to more wear than the others and therefore it is entirely reasonable that they should wear faster. If you used a standard krab in such a way, you wouldn't be surprised - it would be your 'old, knackered, falling and lowering off' krab.

Be reasonable.

Alternatively, you could argue that you are using it in entirely the wrong way - as a 'drag reducing' krab it should be used on all the bolts where you don't think you're going to fall. As for a lower off, more resistance on the lower off krab means reduced load for your belayer and belay device. Off course, then your rope would take more of a beating.

All that energy has got to go somewhere.


daualset 30 Oct 2012
Copied form the user guide:

“Major axis gate closed strength is 24kN but note the integrity of the roller and bearing can be damaged at loads of 11kN or
greater. This however is uncommon under normal climbing usage.
The Revolver is NOT designed for use on zip wires, Tyrolean traverse, top roping or other situations where prolonged use
could cause damaging build up of heat
13.1. WARNING The Revolver is designed as the rope clipping biner in a quick draw set. The rollers surface can be damaged
if the Revolver is clipped to wires, bolts and pegs. This in turn could cause damage to a rope. Always ensure the Revolver is
clipped in the correct orientation (refer to pictograms).
13.2. Incorrect clipping as described above will however not affect the integrity or strength of the Revolver.
13.3. All reasonable steps should be taken in use to avoid excessive contact with dirt, sand, grit etc i.e avoid dropping or
discarding the product in areas where the above are prevalent
 nniff 30 Oct 2012
In reply to daualset:

So, in this context, what's the difference between lowering off and top-roping? You say you don't use them for top roping but do habitually use them for lowering off.

daualset 30 Oct 2012
Thanks THEDATASTREAM for the thread you provided... It looks like other people have found that the load doesn´t fall completely on the pulley.

BLANCHIE14C thanks for summing up in different/better words what is happening to the carabiners.

"The roller and side of the crab rubbing when used in a trad set up would never wear with no load to them but in sport, with 15 stone of climber loading that roller frequently I see the roller being pulled in one direction or another, only a mil either way, but the roller will comtact the crab and a huge amount of friction will be generated as its such a small surface area"

In my opinion it isn´t the bearings that fail by themselves but the fact that the rollers diameter reduces due to friction thus exposing them which then leads to seizure.

In regards to how I use the carabiners:
Crux bolts: I try to use a revolver on cruxes where I might fall so as to reduce rope wear when falling and pulling up
First Bolt: I sometimes use a revolver if the climbing to the second bolt is safe and it´s a route where the belayer would want to move away from the base of the cliff
Big direction changes: Under roofs or before and after traverses
Anchor: If I have any revolvers left i leave one on the belay
daualset 30 Oct 2012
In reply to nniff: That´s a difficult one... Dmm refers to prolonged use and heat build up. I guess when top roping once you've finished the route you're only hanging from one point. On the other hand if you lead a route andf then lower off you´re hanging form one point but still have all of the friction created by the rope running thorugh all of the other draws in the route. I suppose a lot more heat build up when lowering in the first case than in the second
daualset 30 Oct 2012
In reply to the sling diameter commented by various forum members I found this in the user guide:

"All connectors are tested using steel pins of diameter 12mm, if in doubt check compatibility of mating parts before use.
Care must be taken if this connector is likely to be loaded using wide straps (>12mm wide) as this may reduce the strength of
the connector if loading occurs. If in doubt please consult your supplier or DMM."

I´ll have to measure the Spirit slings and see how the carabiner loads in comparison to an 11mm sling.

Photo2brv is of a revolver which was used on a narrow sling (the one that comes with WC heliums) and still has the same problem so it can´t be the only factor.

 jon 30 Oct 2012
In reply to daualset:

I'd say that lowering someone 35m off an overhanging sport climb is going to warm the krab up a bit.
daualset 30 Oct 2012
In reply to nniff:

That would be true if I only had one revolver but I have five (or at least I had five... now only 3 work) so the work load gets pretty evenly spread between them.

I use them to reduce drag... on falls. I guess they´re rated to 11kn for the roller and 24kn for such a purpose
daualset 30 Oct 2012
In reply to jon: I suppose that depends on the amount of friction in the pulley which in turn is conditioned by the amount of friction in the whole rope/draw system up until the belay
 jon 30 Oct 2012
 biscuit 30 Oct 2012
In reply to daualset:

And if there is very little total friction in the rest of the system, due to the Revolvers below the anchors, then more of the energy of the lowering climber will go through that top lowering draw(s) than normal.

They are made to reduce friction and take the odd fall not take 10-15 secs of bodyweight lowering i suppose. It could be this that is causing it. You do seem to be using them slightly differently than others/intended.
 Monk 30 Oct 2012
 nniff 30 Oct 2012
In reply to daualset:

So, having slung a shovelful of mud at DMM, are you going to concede that general opinion is that the wear that you have noted is a result of misuse and not poor design? There's nothing wrong with misuse, mind, indeed 'creative misuse' is often a good thing. However, you need to recognise that there are consequences.
daualset 30 Oct 2012
In reply to nniff:

Sorry but when dig I sling a shovelful of mud at DMM? As I said revolvers are some of the best gear I have ever owned.

I only created this post because my revolvers haven´t lasted very long and I wanted other forum members to share their experiences and how they use revolvers.

Above all they are carabiners. In my understanding they should do what other carabiners do with the added benefit of reducing drag. In no part of the user guide is it written that these carabiners can´t be fallen on or used to lower-off a route. I might be in the wrong for using a couple of them on petzl spirit slings which are 15mm wide but I have other revolvers which I use on 10mm wide slings which show the same wear.

So am I misusing them? I don´t know... I don´t think so. Hopefuly somebody from DMM will appear on this post and help clarify these concepts.

P.S. I got a second reply from DMM expressing there interest in examining them. Nothing was mentioned about misuse
 Jon Ratcliffe 30 Oct 2012
In reply to daualset:
"I use them to reduce drag... on falls."

Why would you want to do that? Doing this you're increasing the force of the fall on you and your belayer. I would hate to belay you lobbing off all the time..

Clearly the Revolvers weren't meant to be hammered like this, yes they're brilliant on big trad pitches and possibly even for the odd draw on a long meandery sport route but there's a reason everyone I have ever met sport climbing, including all those sponsored by DMM, all use 'normal' crabs for sport quickdraws...because they are the most suitable for the job.
DMM even say talk about only having "a couple" on your rack, and then refer to a 'trad' rack.

Yes you can use them in any way you like but there are limitations and best uses for all hardwear.

My advice would be to invest in a nice set of actual sport climbing quickdraws like the Petzl Spirit or DMM Alpha Sport with nice smooth and wide rope baskets...basically designed for the job, and about half the price!
daualset 30 Oct 2012
In reply to Jon Ratcliffe:

I also wonder why none of the sponsered athletes use them... Falling on revolvers is like having the plushest rope ever, it´s almost impossible to get a hard catch. Pulling up after the fall is easier on the climber and the belayer. You avoid also avoid both core and sheath damage to your rope.

As I mentioned before I only use them on the first bolt when a fall is pretty much impossible and then I use them at my discretion above the 4th bolt.
 nniff 30 Oct 2012
In reply to daualset:

Well, your very opening gambit is DMM Revolvers. D..... F....

So, seeing as the internet never forgets, if you now google DMM d... f.....s it's the #1 hit. Seeing you have yet to establish anything of the sort, I'd say that more than a bit off. I'd say they have every right to be a bit hacked off. Small manufacturers like DMM put a lot of effort into building and maintaining well-deserved good reputations and baseless allegations of this sort are unwarranted.



daualset 30 Oct 2012
In reply to nniff:

Thanks for bringing that to my attention. I have asked the moderator to modify the title of this post. I never intended to be derrogative towards DMM as they have my greatest respect.
 Jon Ratcliffe 30 Oct 2012
In reply to daualset: You don't seem to understand the part that friction in the system plays in the force of a fall...I can only presume you get such a soft catch because your belayer is flung so hard through the air...

Any wear saved on your rope is bound to be put onto something else, in this case it's your Revover's.

Anyways, you obviously know more than those at DMM and those climbers sponsored by DMM and the vast majority of people who go sport climbing regularly so I'll leave you to it.
daualset 30 Oct 2012
In reply to Jon Ratcliffe:

Pretty much all of my friends have bought at least one revolver since trying them out sport climbing. It´s amazing how well they work.

Have you fallen on one?

Friction isn´t magically erased but is reduced a fraction. Don´t think that all of my belayers have to unstick themselves form the first bolt... More than the actual fall I find the benefits to be in pulling yourself back up.



 wilkie14c 30 Oct 2012
In reply to daualset:
> Friction isn´t magically erased but is reduced a fraction.

The effect of friction felt by the climber falling is reduced but as you say, it isn't magically erased, its still there but transfered to somewhere else, in this case to the side of the roller/crab. I think the only way to reduce this wear is for the crab to be redesigned with a roller bearing in the roller/pulley and more importantly, thrust bearings between the crab and roller sides. This of course would render the crab too heavy, too bulky and too expensive to be practical.
 jkarran 30 Oct 2012
In reply to daualset:

> P.S. I got a second reply from DMM expressing there interest in examining them. Nothing was mentioned about misuse

So send them back, see what they say. It looks to me like they've had a lot of hard use in the presence of something quite abrasive.

jk
 itsThere 30 Oct 2012
In reply to daualset: man up and climb back up. instead of pulling yourself up and if your get that much rope drag then you are doing something wrong.

also as previously pointed out reducing the friction through the draws will increase the force on the rope, so youve got your self a nice false economy in terms of wear and tear on the rope. plus the cost of revolvers.
 Jon Ratcliffe 30 Oct 2012
In reply to daualset: Yes, I have one on my sport rack and one on my trad rack....from what you were saying earlier in your thread it sounds like you use quite a few when sport climbing and always use one for the first clip...and you wonder why they have worn relatively quickly...anyways you do seem to change the context of use and reasons why throughout this thread depending on how people have responded to what you have previously said!

And yes, I have fallen on one.
daualset 30 Oct 2012
In reply to itsThere:

You´ve got me there... Xd. I didn´t mean to imply that there was drag just that the repeated process of falling then pulling oneself up in the same spot is in my opinion one of the most contributing factors to rope wear.

I understand that the forces are distributed more evenly along the use of the rope with pulleys. The period between cutting the end of my ropes seems to collaborate this fact. On the other hand I might be very wrong...

 itsThere 30 Oct 2012
In reply to daualset: i could be wrong too, i didnt think about the distribution of force, because there isnt that much friction. so i thought the peak force would be the problem. be interesting to see what DMM say.
daualset 30 Oct 2012
In reply to Jon Ratcliffe:

Copied from a previous post:

In regards to how I use the carabiners:
Crux bolts: I try to use a revolver on cruxes where I might fall so as to reduce rope wear when falling and pulling up
First Bolt: I sometimes use a revolver if the climbing to the second bolt is safe and it´s a route where the belayer would want to move away from the base of the cliff
Big direction changes: Under roofs or before and after traverses
Anchor: If I have any revolvers left i leave one on the belay

I also mentioned before that at the most I have used 5 revolvers. Just because I have 5 revolvers doesn't mean I always use all 5.

Please refer to where in this post I have changed the context of use!

I'm trying to give as broad a picture as possible regarding my use of this piece of gear so people can compare it with their own and the results they have had with Revolvers
 deepsoup 30 Oct 2012
In reply to daualset:
> I have asked the moderator to modify the title of this post.

Cool. The new title is much better, nice one. :O)
daualset 30 Oct 2012
In reply to jkarran:

I´m sending them back next week... I´ll be sure to let you know what they say.

Regarding the abrasion. Do you say that because of damaged surface of a couple of carabaniers? That´s what coarse sandstone does to your gear...

 AJM 30 Oct 2012
In reply to Jon Ratcliffe:
> Why would you want to do that? Doing this you're increasing the force of the fall on you and your belayer. I would hate to belay you lobbing off all the time..

They allow more of the rope to stretch fully and mean you as the climber experience a lower fall force than without one - hence why falling onto one is such a smooth experience. It also makes it harder for inexperienced belayers (those who don't know how to dynamic belay properly, which usually seems to involve lots of moving round anyway) to give you a hard catch.

In terms of the use of revolvers on the first bolt, again it makes it easier for your belayer to deliver a dynamic catch - I certainly picked this up from a well known sponsored name (not by dmm though I don't think, so they liked them so much they might have even had to pay for them!) and have found it a useful trick.

But then as I said above somewhere, mine aren't worn like this, so it's clearly load they are more than able to take. I sometimes put them on lower offs too, because I've usually got one left on my harness at the top if the route is a fairly straight line.

 jkarran 30 Oct 2012
In reply to daualset:

> I´m sending them back next week... I´ll be sure to let you know what they say.

Cool, that'll be interesting.

> Regarding the abrasion. Do you say that because of damaged surface of a couple of carabaniers? That´s what coarse sandstone does to your gear...

No, because the ones with really bad axial play look like the roller has been eaten away rather than deformed. If it was clean aluminium on aluminium wear I'd be surprised to see so much material removed.

I wonder if the rollers are heat treated?

jk
daualset 31 Oct 2012
In reply to AJM:

It´s good to hear that someone else on this forum uses revolvers in pretty much the same way.

Maybe you could post a couple of pictures of your revolvers and mention what slings you use.

Cheers
 AJM 31 Oct 2012
In reply to daualset:

They either live on dyneema 60cm slings (probably 12mm or so?) with those little rubber keepers if they're being used for trad, or on the fat petzl sport tapes, again with keepers, if being used for sport.
Simon Marsh 31 Oct 2012
In reply to jkarran:

JK - The rollers are solution treated / aged 7075 - the same material as used for the back bar.

In terms of clarity this was part of a mail sent to the OP yesterday along with a request to get the biners back for examination:

"I would just say that I have never seen wear like this on a Revolver before. It looks as is one side of the pulley wheel has been ground away in the worst case image.

The 16mm rubber retainer is too wide to sit correctly in the top apex of the Revolver and might cause offset loading as mentioned in other replies to your post on UKC – if this is combined with dusty/gritty conditions and long lowers it might be possible to get serious abrasion of the pulley roller.

- Grit gets in the space between the back bar and pulley wheel
- The rubber retainer – especially with a stiff QD tape - stops the Revolver from sitting correctly and the Revolver is held at an angle.
- Thus on being loaded the roller is forced - on the end which is lower – against one side of the pulley recess in the back bar.
- On rotation abrasion will likely occur between the side of the pulley and the side of the recess that are being pushed together – this will be under load and potentially at speed aggravating any possible wear..

Pure speculation, but potentially an explanation."

Our new indoors test tower is now up and running and I'll try to get some simulated tests going

Regards

Simon Marsh

DMM International





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