Ultralight camalot replacement interval

^^^^touche

I should say I buy a new rope every year... I got a plie of old(ish) ropes

So a friend of mine is selling his ultralight rack.  The stems/slings are dated from 2016.  The thing is these cams are maybe used twice.  And never whipped on.  They are in new condition and have been stored in a plastic sealed container for the past 6 years.  Wondering if younthink it's worth the purchase.  He's offering 500$ for a .5 to #4 (#4 is not an ultralight)   

Would you buy? Or price should be cheeper or the lifespan is too short?  Or get them and go play and not give a shit about the slings.

alpinist 47wrote:

I personally replace my entire rack every 10 years

Ropes yearly

Peace of mind 

I wish I had the money for this

Alex Ghiggeriwrote:

So a friend of mine is selling his ultralight rack.  The stems/slings are dated from 2016.  The thing is these cams are maybe used twice.  And never whipped on.  They are in new condition and have been stored in a plastic sealed container for the past 6 years.  Wondering if younthink it's worth the purchase.  He's offering 500$ for a .5 to #4 (#4 is not an ultralight)   

Would you buy? Or price should be cheeper or the lifespan is too short?  Or get them and go play and not give a shit about the slings.

* Unless you are already at the extreme end of weight savings, I wouldn't recommend buying UL .5 and maybe not even .75 (not a whole lot of weight saved for the price tag).  Similarly, I would recommend an UL#4 before any other UL cams.  So IMO, this isn't a great "ultralight rack" even if it were brand new.

* Even if you wanted exactly those cams, by my math this is only a 25% discount over retail.   You can buy these cams at 25% several times per year; so it is basically no discount off the routine sale price.   You'd be doing your friend a favor to pay that much for those cams if they were brand new, never mind used and six years old.

* Buying anything from a friend could potentially impair your relationship in the future.  You'll always wonder if you overpaid and they'll always wonder if they left money on the table.  And that's setting aside the possibility that you could get hurt due to equipment failure.

Alex Ghiggeriwrote:

So a friend of mine is selling his ultralight rack.  The stems/slings are dated from 2016.  The thing is these cams are maybe used twice.  And never whipped on.  They are in new condition and have been stored in a plastic sealed container for the past 6 years.  Wondering if younthink it's worth the purchase.  He's offering 500$ for a .5 to #4 (#4 is not an ultralight)   

Would you buy? Or price should be cheeper or the lifespan is too short?  Or get them and go play and not give a shit about the slings.

Why would you rely on another person's opinion to buy these cams?

I wouldn't purchase these cams but that's just me. I don't buy used gear, ever.  Personally, I don't put much stock in the due dates on soft goods. I give it my personal test of, is it fuzzy, dry or bleached and call it as I see it.

Ask yourself,
'Am I going to freak out in 4 years when the due date on the stem expires?' If yes then the cams are way way overpriced.
'How many trad pitches per year do I climb?' The more the better because they do have a life span and I'd put it at slightly more than the clipping sling. Only because it's shielded by a plastic cover.

Brand new, full price this set is $670 and I sure if you looked hard enough you could get it for $600 or slightly less but that would require patience and work.

Jim Tittwrote:

Fundamentally it is all just a guess, there are no set criteria. At a major cam manufacturer I was involved with we decided over a few beers 10 years was the lifespan, science didn't come into it. The theory being the customer had had their moneys worth from what is effectively a disposable item. For my products (bolts) it's worse so we just give best case (forever) and worst case (one use).

That mirrors what I see as often being the decision-making making in the real world for comparable issues. It's a marketing/legal/economical process, much more than an engineering one (as long as one respects engineering realities).

I find it funny that people seem to expect to get "the real answer" or "the real number" for questions such as this. On the one hand, it's incredibly hard to actually get solid data to certify that some cam will actually still meet MBS up to, say, 30 years of storage without significant usage (30 years being the out of my %?$# guesstimate at a real value for this). On the other hand, you can know for sure that 10 years will work, and what you're really trying to achieve (as a company/manufacturer) is give guidelines to customers and avoid lawsuits. So the process described by Jim makes a lot more sense, unless you're manufacturing pacemakers or space telescopes.

I also find it somewhat funny to discuss the durability of a product which fundamentally is design to trade off durability, in favor of weight-saving. If I ever buy ultralights, it means I'll be climbing pretty hard trad routes where the weight difference may actually matter in my performance. Thus I expect to fall on them (e.g. why exactly would I use UL for some casual, slabby 10- finger crack?). I wouldn't expect the UL to stand up as well to repeated falls and wouldn't be surprised to see lobes deformation much earlier than with standard models. Hence my guess is that my main concern about the lifespan of that product isn't so much aging but just the simple fact that it's not meant to stand to abuse.

J Bwrote:

The stem of ultralight camalots is made of Dyneema, which is a brand name for UHMWPE yarn. UHMWPE yarns are also used in medical devices and body armour for soldiers, so America's National Institute of Standards has been studying their lifetime. Here's one such study where they used elevated temperatures to expedite the aging process: https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=916161

On page 47 they state:

Note that this test only accounts for the impact of aging and does not consider the impacts of mechanical loading.

This sort of literature is likely what Black Diamond engineers used to come up with the (likely conservative) ten year lifespan estimate in the marketing materials. Only those engineers will know what math they did to justify those estimates. Perhaps they did the math based on a 10% derating with the worst case scenario for the cam storage conditions?

Perhaps we can get the how not to highline crew to pull test the stem on an ultralight cam in isolation so that we can see just how strong the stems are compared to the cam's stated MBS. That will give us some insight into just how conservative Black Diamond was when they listed these lifetime figures.

I was trying to figure out when to replace the BD ULs in my rack and I read this post and want to say, thank you for taking the time to write this. Doesn’t answer the question at hand but frames the question well. Much appreciated. 

I'd replace slings every 5 years at the least.  Dyneema. . .maybe more often.

How many falls have you taken on the cams?  How do the springs look, and the rest of the cam too?  You been lubing it regularly?

Link to HowNOT2's UL Testing.

https://www.youtube.com/watch?v=vQf0T-J2H44&t=11s