BD Laser Hard Ice Modification

I've been messing around with modifying a few BD Laser picks. The thought came to me when I tried my friends All Mountain tools with the ice pick. His picks sported a much smaller cross section so I tried to incorporate that into my picks. I even thinned the pick and that worked well too.

Basically I came to this profile and a 2.8mm thick pick. They go in like butter, similar to the Cassin pick and much better than the Petzl pick. The removal has improved dramatically too. None broken and I've hit rock plenty of times.

The height goes from 11mm to 9.5mm and thickness is thinned to 2.8mm.
The yellow is what is machine away.

That's awesome! Now if someone can fix the new Petzl Ice pick!

hitting rock isn't what breaks picks...

Keenan Waeschle wrote:hitting rock isn't what breaks picks...

Seconded. Metal fatigue breaks picks. You aren't likely to personally break one, but you also have no way of assessing how much additional risk of breaking you have added by removing that much metal.

I'll pass.

20% metal removed that's not huge but the performance is way better. Plus the added bonus of the picks not getting stuck.

rocknice2 wrote:20% metal removed that's not huge

It may not sound like 20% is a big difference, but you have zero engineering knowledge and your testing consists of actually climbing on it.

You used the term "machined" in your original post which leads me to believe that you aren't doing this by hand. Just be aware that the heat created by machining your pick down can alter the properties of the metal.

Rockandice2 is a experienced machinist. He knows what heat can do

my question is why not just use Cassin tools?

will archer wrote: Just be aware that the heat created by machining your pick down can alter the properties of the metal.

No heat to speak of. They come out barely lukewarm.

"Why not just use Cassin tools?"
Because I own Cobras and Fusions ..... and a machine shop.

Why not adapt the Cassin picks?

rocknice2 wrote: "Why not just use Cassin tools?" Because I own Cobras and Fusions ..... and a machine shop.

There's a For Sale thread on MP. Just kidding

rocknice2 wrote:20% metal removed that's not huge but the performance is way better. Plus the added bonus of the picks not getting stuck.

I beg to differ. 20% is a lot of metal, particularly when you consider that the stock picks are already highly engineered to make a pick as high performance as possible at a given level of robustness. Even then picks break.

Again, you have no way of assessing the validity of your stance that the metal removed does not substantially increase the probability of breaking a pick. For all you know (I certainly have no clue), removing just 10% of the metal halves the fatigue cycle life of a pick. You simply don't have the statistical power to make any claim to that.

Considering the consequences involved, I would caution people against making such an extreme mod.

Edit to add: I have also been known to make mods to my picks to change angles, add weights, etc. There is no way I would do what you are doing.

Double edit to add: You also seem to be assuming that the material used in the Cassin and BD picks are the same. Do you know that for sure? They could be a different alloy, treated differently, who knows.

It's a shame the OP is so invested in BD tools. Their V slot, one bolt pick mounting design makes it hard to use other brands of picks. A simpler two bolt design is so much more versatile. I have been playing around with CAMP Awax, 1st Gen Quark, and Trango Raptor picks lately, and with a bit of drilling and other MINOR alterations, these picks are interchangeable. Pretty cool to fit an adze or hammer to the Raptor, for example. One local hardman was known to run Awax picks in his Nomics.

Gunkiemike wrote: One local hardman was known to run Awax picks in his Nomics.

Heard that story too. Im was surprised that Petzl didn't let him design stuff. Petzls loss is another company's gain.

About different metals.. I did hear that Cassin picks are made of from ore mined outta some spot in Italy. That the Cassin steel is stronger than other brands. Its hearsay and I got blasted for writing that last year cause I couldn't give proof.

I have been making similar modifications to my BD tools. I can tell you that penetration and removal improved considerably compared to stock.

Now, before you all start typing "you're gonna die!", consider this:

1. Sure, reducing the height of the cross section results in rapid increase in bending stress (stress will increase as the square of the height of the cross section, i.e. a 20% reduction in height of the cross section will result in a 40% increase in bending stress) (and yes, I am an engineer)

2. Picks do break. They break from fatigue. I have personally broken about 7 of them over the years (all BD's... I've never broken any other brand). They all broke from the same process: a crack that starts growing in the 4th notch until it's deep enough to induce
brittle failure of the remaining metal. I have not broken a modified one yet (and yes, that does not prove anything; purely anecdotal). And the testing is now over, because I have now switched to Petzl tools.

3. Ask yourselves what produces tensile stress at the bottom of you picks... three things:
3a. hanging from them of course, but also, and in my opinion more significantly,
3b. yanking on the tools to remove them from the ice, and finally (and this is specific to BD laser picks),
3c. the downward impact of the flat bottom of the tip onto the bottom of the hole in the ice as the tool is driven in, which results from the curvature of the upper edge of the tip which is unique to BD (this is a bit hard to explain, but hopefully you can see this).

4. because of 3c above, I have been removing that curvature of the upper edge of the tip from BD picks, to give them a square leading edge like all other brands. I think that also makes them penetrate better, which would confirm my theory about downward impact.

5. Fatigue cracks generally need a seed, such as poor surface finish in the notches (look at your BD picks), and/or tensile stress at the surface of the part (BD picks are laser cut, which induces tensile stresses at the surface of the cut).

6. Based on 3, 4, and 5, here's why I think the modification suggested may actually improve fatigue life:
6a. if done with care, it removes the surface layer in the notches and produces a nice smooth finish (unlike the jagged BD finish and its tensile surface layer)
6b. it reduces the energy required to penetrate the ice AND the effort required to remove the tool, both of which reduce bending stresses (refer back to #3c)

And yes, I wrote "may" because of course, reducing the height of the cross section does increase bending stresses. Which effect dominates the other is anyone's guess, or could only be evaluated with considerable detail about the exact geometry, temperature, loading situations, and specific material properties. So, of course, I certainly don't recommend anyone should modify their picks in any way... 'cause you're gonna die!

As long as the hole on the Cassin picks is at the appropriate distance from the tip it wouldn't be to hard to modify.

There is always a trade off between performance and durability. This isn't the first thing I've modified. Some of you seem to be under the impression that everything is engineered to the ragged edge. I traded durability for performance but did it in stages. At one point I was using a 10mm tall x 2.4mm thick pick. This didn't break either. I'm not delicate with my tools neither.

What would be an acceptable durability? Perhaps BD's dura/perf ratio is different from mine and mine from yours. All I can say is they work great for me in hard ice.

This mod is not for everyone but if your comfortable modding your tools and not satisfied with the performance of your BD picks then this may be a goal to work to. Do it in stages to see what your comfortable with.

If your a total brute and snapping your stock picks now DON'T DO THIS MOD.
If your worried about micro fractures DEFINITELY DON'T DO THIS MOD!

Here's what my neighbor (Black Diamond) says about ice picks (other QA questions/answers can be found on their site, inc. one warning about switching picks to other tools). I'm not taking a position on this...well, I guess I am...I'd never switch picks from one brand of ice tools for another for reasons BD explains in another section of the one below:

http://blackdiamondequipment.com/en/qc-lab-gear-doesnt-last-forever-part-i--ice-picks.html

Eric and Lucie, can you post a derivation of your section height and stress relationship?

Pete Wilk wrote:Eric and Lucie, can you post a derivation of your section height and stress relationship?

Assuming you exert a fixed amount of force on your shaft (thereby inducing a fixed amount of bending moment in the pick, M) when you remove your tool, regardless of the design of the pick (Note: this is a BIG assumption, since a better pick design should require less removal force... but thickness and detailed tooth design probably affect removal effort more than height), then the peak bending stress in your pick is:
s = M * (h/2) / (t*h^3 / 12) = (6*M)/(t*h^2),
where M is the maximum bending moment applied to your pick when removing your tool, t is the thickness of the pick at the location where the moment is maximum, and h is the height of the pick at that location.
(look up beam bending stress on Wikipedia if you want a reference)

Eric and Lucie wrote: Assuming you exert a fixed amount of force on your shaft (thereby inducing a fixed amount of bending moment in the pick, M) when you remove your tool, regardless of the design of the pick (Note: this is a BIG assumption, since a better pick design should require less removal force... but thickness and detailed tooth design probably affect removal effort more than height), then the peak bending stress in your pick is: s = M * (h/2) / (t*h^3 / 12) = (6*M)/(t*h^2), where M is the maximum bending moment applied to your pick when removing your tool, t is the thickness of the pick at the location where the moment is maximum, and h is the height of the pick at that location. (look up beam bending stress on Wikipedia if you want a reference)

I have tried to follow this issue over the years and for many reasons. Looking at ice pick failure is of particular interest (I am not an engineer....another type of scientist).

Questions:

1. You are speaking of lateral and not vertical bending moments correct? (Can't recall exactly....apologies.....but stress fractures are introduced...or are starting....in vertical bending, is that correct? Example: when a climber is moving the tool up and down repeatedly to clear it, there MAY be metal fatigue beginning due to this movement? (As a corollary, it may be X times before the pick actually breaks and at an undeterminable point (partly because the fulcrum of various removal attempts would change, all of which are unpredictable (except in perhaps a lab study). Am I way off base (which is usually the case).

2. You say "regardless of the design of the pick". Surely BD Titans (or any dry tool pick) can withstand greater bending moments in both the vertical and lateral planes?
Go out on the edge here and comment on 'torque' use of picks & bending moments (as in try tooling). Thoughts?

3. You sort of answered my Q above re: pick design, however, how/whether the pick is tuned post-market -- would this have an effect on bending moments (in either or both planes)?

4. If "M" is the "maximum bending moment applied to your pick when removing your tool" this seems you are referring to vertical removal and not lateral (in an ideal physics world).

5. #5 makes sense, however you say: "it is the thickness of the pick at the location where the moment is maximum, and h is the height of the pick at that location."

As a practical matter, this would be almost impossible to determine due to many factors (ice conditions, how deep the pick was driven, PRIOR attempts (successful or not), would it not? Seems to me that the only way to solve the equation would be under laboratory conditions, which of course have great value. At least you could get a range of bending moments? Thoughts?

_____________________

Of primary interest to me is the overall metal fatigue in picks inexorably induced by repeated vertical/lateral/twisting of removal attempts.

On various occasions, I've spoken with Petzl, BD, E-Climb, CAMP and Cassin engineers about this very thing. Of course, their answer has been (same one I'd give as a scientist) "it depends". There seems to be no standardized testing for ice picks (such as helmet failure, etc.) Again, thoughts?

(There is nothing proprietary nor patented by any manufacturer of ice picks; quite sure of that but stand to be corrected. This does NOT mean they are made of the exactly the same stuff (basically, probably), just different ratios but maybe a dash of this and that".)

I've been told that careful inspection with an optical instrument that does this sort of thing (not a fully tricked out spectrophotometer) will actually reveal the beginning of stress points, a markedly obvious stress fracture (but that can't be seen with the naked eye) or stress that can, in theory say: "throw away your pick".

Any experience or thoughts re: this? I think most climbers wonder about the life of their picks. (Smart ones - that leaves me out - will always have a spare with them). Certainly, climbers aren't going to visit their local shop & pay $X to have their picks X-rayed (although it may reveal something (besides a reduction in your bank account)). I believe X-raying a representative sample of metal pieces (but mostly aluminum) used by climbing manufacturers such as carabiners (pre-and post loading) is done but I could be way off base here. I know it used to be done on dropped carabiners (but only to determine a range; X-rays should show cracks (I think), if they exist).

But X-raying CrMo (depending on SAE grades) is a different beast altogether, right, and that the technique would not reveal bending moment fatigue, esp. cumulative metal stress??? But to be redundant, would a spectrophotometer be a better approach? Or neither?

I appreciate your post and the time you obviously put into it -- tough stuff to figure out I think.

Eric & Lucie;
I'm not looking for answers other than easy ones, i.e., you may know the answer(s) given your expertise. Please do not spend much, if any time on my Qs.

I know how to clear picks.....that's not my interest, rather, your comments on other stress factors that may be....or are likely to become problems.

Thanks much,

Warbonnet

Warbonnet wrote: Questions: 1. You are speaking of lateral and not vertical bending moments correct? (Can't recall exactly....apologies.....but stress fractures are introduced...or are starting....in vertical bending, is that correct? Example: when a climber is moving the tool up and down repeatedly to clear it, there MAY be metal fatigue beginning due to this movement? (As a corollary, it may be X times before the pick actually breaks and at an undeterminable point (partly because the fulcrum of various removal attempts would change, all of which are unpredictable (except in perhaps a lab study). Am I way off base (which is usually the case). 2. You say "regardless of the design of the pick". Surely BD Titans (or any dry tool pick) can withstand greater bending moments in both the vertical and lateral planes? Go out on the edge here and comment on 'torque' use of picks & bending moments (as in try tooling). Thoughts? 3. You sort of answered my Q above re: pick design, however, how/whether the pick is tuned post-market -- would this have an effect on bending moments (in either or both planes)? 4. If "M" is the "maximum bending moment applied to your pick when removing your tool" this seems you are referring to vertical removal and not lateral (in an ideal physics world). 5. #5 makes sense, however you say: "it is the thickness of the pick at the location where the moment is maximum, and h is the height of the pick at that location." As a practical matter, this would be almost impossible to determine due to many factors (ice conditions, how deep the pick was driven, PRIOR attempts (successful or not), would it not? Seems to me that the only way to solve the equation would be under laboratory conditions, which of course have great value. At least you could get a range of bending moments? Thoughts? _____________________ Of primary interest to me is the overall metal fatigue in picks inexorably induced by repeated vertical/lateral/twisting of removal attempts. On various occasions, I've spoken with Petzl, BD, E-Climb, CAMP and Cassin engineers about this very thing. Of course, their answer has been (same one I'd give as a scientist) "it depends". There seems to be no standardized testing for ice picks (such as helmet failure, etc.) Again, thoughts? (There is nothing proprietary nor patented by any manufacturer of ice picks; quite sure of that but stand to be corrected. This does NOT mean they are made of the exactly the same stuff (basically, probably), just different ratios but maybe a dash of this and that".) I've been told that careful inspection with an optical instrument that does this sort of thing (not a fully tricked out spectrophotometer) will actually reveal the beginning of stress points, a markedly obvious stress fracture (but that can't be seen with the naked eye) or stress that can, in theory say: "throw away your pick". Any experience or thoughts re: this? I think most climbers wonder about the life of their picks. (Smart ones - that leaves me out - will always have a spare with them). Certainly, climbers aren't going to visit their local shop & pay $X to have their picks X-rayed (although it may reveal something (besides a reduction in your bank account)). I believe X-raying a representative sample of metal pieces (but mostly aluminum) used by climbing manufacturers such as carabiners (pre-and post loading) is done but I could be way off base here. I know it used to be done on dropped carabiners (but only to determine a range; X-rays should show cracks (I think), if they exist). But X-raying CrMo (depending on SAE grades) is a different beast altogether, right, and that the technique would not reveal bending moment fatigue, esp. cumulative metal stress??? But to be redundant, would a spectrophotometer be a better approach? Or neither? I appreciate your post and the time you obviously put into it -- tough stuff to figure out I think.

Hi there: I am afraid you're not understanding the problem very clearly... let me try to answer your questions one by one...
1. No, I am speaking of "vertical" moments, i.e. bending that occurs within the plane of the tool ("vertical" plane) when you remove your tool by alternately pulling the shaft away from the ice and pushing in toward the ice. Yes, it is this repeated action that can cause fatigue failure of the pick, typically starting at the neck of a tooth due to stress concentration there.
2. That is what I wrote: different picks can withstand different levels of bending moment, depending on their design.
3. The magnitude of the moment applied by the climber is not dependent on the pick, but simply on how much force the climber is using to remove his picks. However, as I mentioned, the effort required to remove a tool would in reality likely be a function of the thickness of the pick, among other factors. I am not going into twisting issues: proper pick removal from ice does not involve twisting, and I am not about to consider mixed climbing.
4. Yes
5. Sure, it would be extremely difficult and probably pointless to try and estimate the inputs to the equation I provided. Its only value in this context is in estimating the effect of modifying the pick, all other things being equal.

Yes, you can often see the short cracks emanating from the neck of the teeth, well before they result in catastrophic pick failure. If you polish your pick and examine it in good light with a magnifier, you may be able to see them (if they're there...). A common industrial technique for revealing such cracks is dye penetration inspection. It is cheap and relatively easy to do. Look it up. XRaying and the like are not very sensitive techniques to reveal extremely small, closed cracks.