Valley Giants

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cavemonkey

Ice climber
ak
Jun 30, 2017 - 12:22am PT
Truly spectacular having these two fine men making wide cams for us timid folks
cavemonkey

Ice climber
ak
Jun 30, 2017 - 12:25am PT
That scabfest on abracadeaver turned in to a one arm pull-up contest
nah000

climber
now/here
Jun 30, 2017 - 12:36am PT
Tom wrote:

But, for the same price, the Merlin does not provide the same strength as a Valley Giant. But, then again, maybe today, with sticky rubber, ultra-thin lead ropes, microlight carabiners, and a climbing culture weaned on stories about free solos of Half Dome and El Capitan, the strength of a gear placement is no longer relevant.

So, just in case anyone out there wants a "high school shop project" that isn't just a pusher piece, but can actually hold a fall, or be used as a hauling or rescue anchor, and that has over fifteen years of proven use, I will have some more Valley Giant cams ready soon.

There is nothing wrong with pusher-piece cams, as long as people recognize them as such.

Passive-aggressive insinuation that the Merlin is a "pusher-piece" is spot on.

Simply scaling a cam from small to large is analogous to building a skyscraper using the technology of a three-story building.



i don't know if you care... but in the case that you might, your statements above lack professionalism.

they lack professionalism, as in each case they contain statements and/or insinuations that are, given the merlin cams current dearth of testing, simply not knowable.

while you have every right to ask for more testing, to use the language that you are using, when you also build large cams, is to step on some interesting ground.

if this was a bigger market, and there was real money at stake, you would have already received or would shortly be receiving a letter from a good lawyer.

you may not care, and that's your deal.

but you, by all accounts, make a damn good cam, and all you are doing as of your last few posts is dragging your own name through the mud [to at least this observer].



i do hope the merlin cams get more rigorous testing, at some point... but at the end of the day, until they do, buyers will just have to accept the unknowns for what they are...

name calling; unproven insinuations; and aspersions cast on the design process, theoretical modelling and testing that has been done, only makes the person casting stones look less in the eyes of those who understand and accept that the new cam is a bootstrapped project that has only had limited modes of testing.
JoeSimo

Trad climber
Bay Area, CA
Jun 30, 2017 - 10:22am PT
I won't be satisfied until someone makes a #100 cam. THINK OF THE CLIMBING POSSIBILITIES!
SomebodyAnybody

Big Wall climber
Torrance
Jun 30, 2017 - 10:52am PT
I'll add a data point: I've taken repeated whippers onto a VG #9, up to 20ft. I'd guess I took that same fall 7-8 times and have taken a few more up to 15' on other routes. I still climb on that cam and it looks no worse for the wear.

As others pointed out, the pics I posted were from a MtnProj thread, I've bent a C4 lobe similarly from a whipper where some nubbins inside the crack prevented the cam from orienting itself into the direction of fall, causing torquing of the lobe at the axle connection and bending the crap out of it.

Testing in a lab rig unfortunately does not simulate real world conditions. Torqueing at the axle is, in my opinion anyway, a real concern on something with that long of a lever-arm. I look at the lobes on that Merlin cam and immediately think "this would probably not hold up very well to significant torque at the axle/lobe interface". So I won't buy one. Simple. YMMV and all that. Go take some big whippers on it, with nothing else between you and a ledgefall or the deck and let us know how it works out. If you're not willing to go do that, then your opinion doesn't really carry any weight for me.
fivethirty

Ice climber
CA
Jun 30, 2017 - 11:09am PT
fwiw nah000 explained much better what i was being sarcastic about upthread.

tom you make a sweet cam. the only thing you gain by dragging the merlin through the mud is looking unprofessional while also giving the merlin cam a bunch of free advertising and legitimizing it as competitor to your own. focus on why your cams are objectively good, not why they are relatively good to the merlin, etc.

or that's what i would do were i running a business. regardless, thanks for all you work making the VG. it's a pretty niche market and we're lucky to have your product.
SomebodyAnybody

Big Wall climber
Torrance
Jun 30, 2017 - 11:23am PT
You guys that think Tom is doing this to "run a business" are funny. I see it much more as a selfless service to the climbing community. You do understand that its not his "real job", and after all is said and done they probably make him less than min wage for the time/materials invested?

I get it, you want to stick up for your buddy, and probably think it's a really good product. Good for you, and good on him for trying to advance the gear. But Tom is not raising specious concerns out of some desire to denigrate the competition, he's raising the same concerns others identify at first glance. And no, I don't know Tom, have never met him, and only communicated once by email to see if he had any #9s in inventory (he didn't, I bought a used one from a friend).

Late Starter

Social climber
NA
Jun 30, 2017 - 12:21pm PT
Tom...Sent you a message!
blahblah

Gym climber
Boulder
Jun 30, 2017 - 12:35pm PT
if this was a bigger market, and there was real money at stake, you would have already received or would shortly be receiving a letter from a good lawyer.

Real-life laywer here (although a terrible one, as I've learned from ST feedback).
If I were designing, hand-making and selling equipment on which people's lives depended, I think "recieving a letter from a good lawyer" [relating to something like false advertising / product disparagement, I presume?] would be pretty far down on my list of legal concerns.
Jon Beck

Trad climber
Oceanside
Jun 30, 2017 - 12:44pm PT
talking shlt is legal, as long as the talker is offering opinion, regardless of the validity. Promoting false facts is a different story.

Tom only said he would not trust a Merlin to take a fall. It becomes a problem if Tom falsely said "I took a short fall on a Merlin and it failed".

Great discussion on large cams, thanks to both the builders, I look forward to getting my pusher piece :)

God damn, the pusher
God damn, I say the pusher
I said God damn, God damn the pusher man

fivethirty

Ice climber
CA
Jun 30, 2017 - 12:52pm PT
I get it, you want to stick up for your buddy.

I've never met the other guy. Or Tom for that matter.

It's not that talking sh#t is a problem, it's that not mentioning your competitors product by name especially when said competitor is an upstart is pretty much marketing 101. Tom has nothing to prove -- he makes a great product. Merlin guy has everything to prove. By mentioning the Merlin cam, even to express concern about it, only legitimizes the Merlin cam as an alternative.

But like you said maybe Tom doesn't care about running a business.
SomebodyAnybody

Big Wall climber
Torrance
Jun 30, 2017 - 12:54pm PT
Then I was wrong about your motive.

Sounds like the other white knighters in here are friends with the person, and I mistakenly assumed you were the same. My larger point stands.
Alexey

climber
San Jose, CA
Jun 30, 2017 - 02:18pm PT
it is very annoying to read smart ass lengthy passive-agressive lecturing about Tom's professionalism.
back to the subject. I have VG #9 for 5 years, using it [ rare]on some flares in Yos and Moab for free climbing. I never really had a fall which can be qualify as fall , but felt [ subjective] that VG#9 is stable piece because how it design [ proportions size to width] and mentally OK to fell .

I get Merlin#8 because on some routs it nice to have 2#9. The design is slick and light. It felt really light and nice looking. trigger lock was hard to get for me, but Erick help with video. It still not straight forward and hard to make trigger lock with both hands without table . If you go for multi pitch flare [ I don't] not sure you can lock it after first use. I compared Merlin vs VG side by side and Merlin is much more narrow.
I tried Merlin once on route which is wired for me and did not feel the piece is stable as VG because of it width [ subjective feeling] but I will use it again and probably will feel differently.
Anyway, I am satisfy with both Merlin#8 and VG and think it nice to have both of them for diversity.
nah000

climber
now/here
Jun 30, 2017 - 07:49pm PT
fivethirty already made most of my follow up point for me... but to mostly duplicate:

nope. i've never met either cam maker, either.

as small scale makers, i have the deepest respect for what both guys are accomplishing. it is no small feat.

and Tom is of course free to say whatever he wants, however he wants... not that it matters, but i even appreciate Tom's concerns and am in agreement that those concerns, given the current stage of testing for the merlin cams, are entirely legit.

however, i'm also just being direct, that the way he is recently going about his questioning [by calling them pusher pieces and making comments about the design principles that may or may not have been involved] only makes me lose respect for him and his position...

but i get those same comments don't bother a bunch of you and that's all good too...

just don't, necessarily, expect me to shut my yap, just 'cause you find my opinion annoying...

[and Alexey, if you're referring to my post as passive aggressive, i don't think you know what those words mean: i said exactly what i think directly to Tom...]
karabin museum

Trad climber
phoenix, az
Jun 30, 2017 - 08:27pm PT

JoeSimo - here is a #36 cam. Actually named a Mastadon 000

Credit: karabin museum
Display at the Phoenix Rock Gym
Display at the Phoenix Rock Gym
Credit: karabin museum


edavidso

Trad climber
Oakland, CA
Jun 30, 2017 - 09:59pm PT
Tom raises some good points and I think I've already addressed most of them in this thread already - see posts #85, 89, 184, and 186 if interested (and cam pull testing in #211). Unfortunately, I do not have any additional testing data to add at this time.

As far as I know, all cams are rated only for the direction of pull along the axis of the stem. All cams (except maybe some micros) will fail at a much lower load than rated if loaded off-axis and not allowed to rotate. The pamphlet that comes with cams admonishes you not to do this but doesn't give an off-axis load rating. Clint pointed out that link cams are notoriously bad for off-axis loading, for example. As pointed out, larger cams are more susceptible to off-axis loading. Have VG's been tested in a load frame in an off-axis condition? How was this accomplished and what were the results? It is not an easy test to perform or standardize since you actually have to trap and prevent the cam from rotating into its preferred orientation. I think this is very rarely done on even commercially produced cams. Key takeaway - if you want to prevent off-axis loading, please take care to place cams so that they are either aligned in the direction of pull or can rotate to that position.

I am not trying to compete with VG's on strength. When I originally designed these cams, I wanted them to have a strength similar to that of commercially available cams, have the greatest range possible, lightest achievable weight, and be easy to use. The trigger lock was an added feature. As a result, they have about the same strength as a commercial cam, are 65% the weight of a VG9, have an entire extra inch of range vs a VG9, and operate like a smaller cam (single stem with narrow, two-finger trigger). Hopefully they will also stand up to the test of time. The one area where the Merlin #8 will also certainly be stronger and safer than a VG9 is in the crack range from 9-10 inches. I am sure Tom makes a great product and has been doing so for years. Everyone can make their own choice.
Tom

Big Wall climber
San Luis Obispo CA
Jul 1, 2017 - 01:31pm PT
Thanks for posting up Erick.


I have not been talking about off-axis loading of incorrectly placed cams. The buckling failure of the lobes occurs even if the cam is perfectly placed in a perfect testing frame, and is perfectly loaded in the ideal direction.

A big cam under load experiences surprisingly large lateral forces on the lobes, which will deflect and eventually bend them sideways (if the sling, stem and axles don't fail first). No off-axis loading of the cam is required for the lobes to deflect, bend sideways and buckle.

The reason is that the lobes are loaded in compression between the point of contact and the axle. When the lobes deflect to one side slightly, because the cam is not 100% rigid, the compressive force has a lateral component, perpendicular to the contact point-to-axle line. As the force on the lobe increases, the lobe deflects more and bends, which increases the perpendicular force component, which bends the lobe even more, which increases the perpendicular force even more, which bends it more, and so on.

To put it another way, even under proper orientation and proper loading of a big cam, the lobes will buckle under the high compression forces. This is analogous to a long, thin column loaded axially, which will deflect sideways near the middle. No off-axis loading is necessary to buckle the thin column, and no off-axis loading is necessary to buckle the lobes of a big cam.

In the real world, irregular crack surfaces will induce higher lateral force components, compared to a testing frame. A testing frame presents the ideal environment to minimize the lateral forces on the cam lobes; any deviation from that environment will increase the lateral forces, and cause the cam lobes to buckle at a lower load.


Again, no off-axis loading is required for a big cam's lobes to fold sideways and buckle. And no off-axis loading is necessary for a big cam to fail at a load that is considerably less than what is obtained in a laboratory using a testing frame.


EDIT:

Earlier when I spoke of off-axis loading of the lobes, I was talking about the out-of-plane, lateral loads that are perpendicular to the contact point-to-axle line. Those out-of-plane loads are components of the compression forces in the lobes, and are not due to incorrectly placing or loading the cam. They occur no matter how carefully the cam is placed and loaded.

I apologize for not being more clear, regarding the nomenclature.

edavidso

Trad climber
Oakland, CA
Jul 2, 2017 - 10:46pm PT
Tom, thanks for clearing up what you were talking about. I figured you were talking about off-axis loads since those were the terms you were using. Buckling, is indeed a different failure mode though the end result looks the same. I have also mentioned buckling as a failure mode in my previous posts. Buckling is as you've described - the sudden, catastrophic failure of a compression member subjected to nothing but axial loading. The critical buckling load will be lower if subject to eccentric loading (e.g. axial load is applied at edge of lobe instead of center of lobe and therefore causes a small bending moment) or any off-axis force that causes a bending moment (I believe these would be the lateral loads you talk about).

I have designed these cams specifically to resist buckling. They are not the same as the Camalot design where the lobes have a fair amount of play out-of-plane. In the Merlin design on each side there are two lobes that sit right next to each other separated by small spacer washers. The other lobes are trapped on the outside by the dogbone shaped endcap and the inner lobes are trapped on the inside by a step in the axles or control horns. This architecture is not possible with the Camalots because the springs get in the way; the springs on the Merlin are all internal to the sets of lobes. So there is very little play in the Merlin lobes out-of-plane. What further resists buckling is the double axle design since the lobes are trapped in their plane on both axles. This has the effect of reducing the "length" of the compression member. This helps quite a bit since buckling load goes as the inverse square of length.

My load frame, itself, does nothing to resist buckling. When I do fail a cam in buckling, which I expect to be the first failure mode in a 9" crack, I will post the video and results. I'm probably not far from buckling one in the 8" crack either at a load at or above 12 kN. I agree that real world loading conditions are rarely ideal as they are in a load frame but this is how all cams are tested and rated. I believe the main culprit in cams failing earlier than they should is off-axis loads. These cannot always be avoided but good placements can prevent the worst of the off-axis loads.
Tom

Big Wall climber
San Luis Obispo CA
Jul 3, 2017 - 02:39am PT
Erick,

You are right on it.

That dog-bone that rides along the cam lobe, which will suppress outward lateral deflection of the lobes, is brilliant.

But, inward deflection needs to be addressed.

Test.


JUST DO IT.



Break one, in a wide testing frame, and see what happens. Don't use a webbing sling. JUST DO IT.


Load a Merlin cam until the lobes bend, buckle and fold sideways, and report the results.


And, then it will be easier for people to decide if they want a VG piece that can pull a truck out of the mud, or Merlin piece that is strong enough for a great rock climbing experience.

Matt's

climber
Jul 3, 2017 - 08:14am PT
And, then it will be easier for people to decide if they want a VG piece that can pull a truck out of the mud, or Merlin piece that is strong enough for a great rock climbing experience.

Tom, you really are backing yourself into a corner here!!
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