NEW Black diamond Z4

Harumpfster Boondoggle wrote:

I'll suspend judgment until you present actual evidence as you seem to presume every small cam is placed behind an expanding flake.

I am absolutely not making that presumption.  What many people don't understand is that metal is flexible and can be compressed, so when you put a force on small metal parts (the axle and the lobes of the cam) you bend the axle and compress the lobes of the cam.  Obviously, increasing that force compresses the lobes and bends the axle more.  Small cams have very little room for expansion to account for these changes in cam geometry and can therefor pull out without any expansion of the crack itself.  

Matt Castelli wrote: David k/ others - anybody have links to various brand/model cam angles? The way back machine link didn’t work.  Metolius, bd, wc, dmm, totem etc would be an interesting comparison, particularly any different cam angles between single/double axle cams of the same manufacturer ( or totem totem vs regular) (I looked and didn’t find good info)

Still getting a lot of value out of this thread, so thanks for the info

Hm, it looks like MountainProject is mangling WaybackMachine links. I fixed it by wrapping it in a TinyURL. See here.

This is only a measurement of a single Black Diamond C4 Camalot #3, though.

Ken Noyce wrote:

The funny thing here though is the fact that micro-cams popping typically do so due to the smaller range, and not because of not having enough holding power.  In the case of small cams, more holding power actually translates into more force on the small axle making the placement more likely to rip and not less likely.

Hm, do you have a source for this? The only way I can think that higher force on the axle would cause a placement to rip is if the higher force causes the axle to deform, which would be fairly easily fixed with a thicker/stronger axle.

David K wrote:

Hm, do you have a source for this? The only way I can think that higher force on the axle would cause a placement to rip is if the higher force causes the axle to deform, which would be fairly easily fixed with a thicker/stronger axle.

One thing that you should always take into consideration is the friction between the lobe and the axle...........

Ken Noyce wrote:

I am absolutely not making that presumption.  What many people don't understand is that metal is flexible and can be compressed, so when you put a force on small metal parts (the axle and the lobes of the cam) you bend the axle and compress the lobes of the cam.  Obviously, increasing that force compresses the lobes and bends the axle more.  Small cams have very little room for expansion to account for these changes in cam geometry and can therefor pull out without any expansion of the crack itself.  

Still not remotely convinced this is a thing.

Jim Titt wrote:

One thing that you should always take into consideration is the friction between the lobe and the axle...........

I'll speculate that this would be less on totem cams because their design would have lower forces on the axle.

Jim Titt wrote:

One thing that you should always take into consideration is the friction between the lobe and the axle...........

Oh, yeah. Didn't think of that! Is there a potential tradeoff of having a thicker axle (for strength) and a thinner axle (for lower friction)? It seems like this could be a limiting factor.

David K wrote:

Oh, yeah. Didn't think of that! Is there a potential tradeoff of having a thicker axle (for strength) and a thinner axle (for lower friction)? It seems like this could be a limiting factor.

I was kind-of intimating that before one discusses the coeff. of friction of rock and the niceties of 0.5 degrees cam angle some consideration should be given to other parts in a cam......

About time someone mentioned that. Maybe there is a little more to the story than "holding power" or we would have all flocked to Metolius long ago.

By the logic of a couple degrees of camming angle/holding power trumps all else, aliens with their mushy lobes and high camming angle should be leaping out of cracks at the slightest hint of tension on the rope. Clearly that is not the case.

Kolin Powick fondling some Z4’s for 15 minutes straight for you gear nerds out there.

https://youtu.be/rMEa6errAUY

Good info on the new z4 here:

Damn were the ultralights really announced in 2015? 

Life goes so fast... ;-)

"Mechanically expanding climbing aid"?  Uh-oh, Camalots are aid...

Gold Plated Rocket Pony wrote: Good info on the new z4 here:

The .75 x4 XL edition. The Ron Jeremy of cams....

Foy O wrote: They are for sell now at REI and backcountry among other stores.

EDIT: for pre-order, not immediate purchase

Do we still hate backcountry?   Also didn't see them on there. 

Brad Johnson wrote:

Do we still hate backcountry?   Also didn't see them on there. 

Us Americans always say, if it saves a dollar, then who cares if they're evil (see United Airlines, Uber, etc.)

The green is not available for pre-order yet

Ordered myself a .1 to sample from REI
If it's good maybe these will replace my Totem Basics. Or my master cams. I haven't decided.