Why did my crampon break?

[Umsaskis]

Today the front connector bar broke on my flexible crampons. They are Italian CAMP Premana crampons, very similar to SMC except that the hinge is between the heel and center, rather than between the center and front. In both kinds of crampon, though, the actual pivot point is the center bar. The connector bar between the center and front snapped in two. I wear a rubber-bottomed leather boot with them and assumed there was no problem with the flexible boot putting too much strain on the crampon since the crampon is hinged. I bought the crampons last year used. While it's possible that there was a crack or weakness from previous use, I'm more concerned that I caused the break by using the boots that I do. I noticed today (before it broke) that this hinge was bent a bit and thought I should check it out when I got back, but never got the chance.

I'm going to get a new crampon (probably have to get a pair), but I don't want to break that one too. Are some boots too flexible for hinged crampons, regardless of where the hinge is? I didn't think that was posssible, but my boots are pretty flexible, which is one of the reasons I like them. I certainly don't want to get new boots.

 

[Kevin Rooney]

Tough to beat the quality of Grivel or Black Diamond. If that happened to me, I'd get some Grivel G-10's or BD Contacts. If the Grivels, make sure the connector bar is set in flexible mode.

 

[jfb]

I think I may have a pair of those crampons and they are pretty rugged. They can be disassembled into three pieces, the front with 4 vertical points and two front points, the center bar with two vertical points and the heel with 4 vertical points. The center bar has the two hinged connector bars attached and the distance between the two points on the center bar is also adjustable. If your front connector bar broke, there's a chance it was because of metal fatigue from repeatedly straining the bar because the soles of your boots are flexible. It could also have failed because of previous damage or a manufacturing defect. You may be better off with a pair of crampons that have the hinge at the rear of the front piece, but then they might just break at a different place. On the other hand, stiffer boots would probably also be a wise choice to prevent breaking your new crampons.

 

[Umsaskis]

Well, I looked at them again this morning, and discovered that one of the teeth had also snapped off on the other crampon. Now, that would have nothing to do with strain, unless it was from mis-stepping on a rock and twisting the crampon, but I think they should have stood up to that. My only thought is that I usually put them in my pack next to my hot water bottle, then pull them out and dump them on the ice. Could that cause the metal to become brittle?

I think that having the hinge at the rear of the center bar does create more strain than having it at the front, so I'll make sure my next pair has the hinge at the front.

Any thoughts on why the tooth as well as the connector bar broke?

 

[Umsaskis]

Just flexible - one hinge. They are similar to the SMC Superblue (without the wavy frame and with the hinge at the back of the center bar rather than the front). I'm thinking I should have adjusted them so that the center bar (and thus the flex point) was closer to the front of my foot. I'll do that with the next pair. But any other thoughts would be welcome.

 

[Chip]

My only thought is that I usually put them in my pack next to my hot water bottle, then pull them out and dump them on the ice. Could that cause the metal to become brittle?

No

I think that having the hinge at the rear of the center bar does create more strain than having it at the front, so I'll make sure my next pair has the hinge at the front.

That design does not sound right to me either.

Any thoughts on why the tooth as well as the connector bar broke?

I think it's been a tough winter on crampons, lots of rock right under the ice and snow. I broke a tooth on my Grivel Air Tech Lights in the Catskills. These are light, but the metal seems soft, dulls quickly, then needs to be resharpened after each outing. I won't buy the Air Tech Lights again. Camps are a little less expensive, but I've heard there's virtually no customer service.

 

[Mike P.]

What kind of boot? They can be too flexible for hinged or any crampons, especially if out a lot. If you wore them once or twice a year you might get a few years out of them.

Many people wear flexible boots & get away with this but I don't think the folks at Grivel or BD endorse this practice.

I would think heat would have to be more than a bottle of hot water for heat. The one thing that you are not supposed to do is sharpen crampons with a grinding wheel (electric grinder)

 

[Umsaskis]

What kind of boot? They can be too flexible for hinged or any crampons, especially if out a lot. If you wore them once or twice a year you might get a few years out of them.

Many people wear flexible boots & get away with this but I don't think the folks at Grivel or BD endorse this practice.

So then my question is: What kind of boot is stiff enough to be able to get a lot of years out of your crampon? Would it need a shank? I hate to give up my oh-so comfortable Nor'Easters, but I may need to. Can I really use a typical Sorrel type boot, or is that too flexible?

 

[jbrown]

I thought I'd wait and see how this played out before throwing in my 2 pennies worth...

Having the hinge at the back of the spreader bar is exactly the problem.
The flexing of a boot occurs at the front of the sole just behind the ball of the foot. If the hinge was at the back of the bar, i.e. just in front of the heel, this would take the hinge out of play, put all the stress at the front of the bar and act as basically a rigid crampon. Flexible boot + rigid crampon = broken gear.

It sounds to me like either a design flaw, or user error. (PEBKAC!)

Here's an alternative for you: Kahtoola They're super flexible and made for any kind of footwear. The new steel model has 1" points. (I haven't used them, but have heard great stuff from people who own them.)

 

[bill bowden]

Breaking crampons/flexible boots

Sorrel type pac-boots have been used successfully with flexible crampons for many years but the marriage has always been an unpleasant one. The boot and crampon both flex, but in different places and occasionally the crampon gives way under the strain (especially if you are a large person).
What to do?
The old-fashioned solution was to buy an insulated steel-shanked insert from LL Bean and put it in the flexible boot which reduces boot flex and gives your foot much better support.
The alternative was to get a plastic double boot which did not flex and would take just about any correct-sized crampon, but could be very uncomfortable.
More nearly modern solutions are insulated leather boots with a stiff shank (some even have ridges to take a step-in crampon)
An even more modern and distinctly soft core solution is an insulated single boot which gives better comfort and foot and ankle support and will take Grivel G10 or 12 or AustrAlpina 12 point Crampons. The bindings are easier to fit than more traditional bindings.

If you want to hike with a flexible boot and a flexible crampon, it is pretty important to have the boot and crampon fit each other properly. Often a little carving on the sole is necessary to get the crampon to fit well. a properly fitted crampon will stay on the boot even before the straps and tightened. This minimizes flex in both boot and crampon.

sorry about the length of the post

 

[Remix]

FYI, here are some recalls involving Crampon Failures

 

[Umsaskis]

Having the hinge at the back of the spreader bar is exactly the problem. The flexing of a boot occurs at the front of the sole just behind the ball of the foot. If the hinge was at the back of the bar, i.e. just in front of the heel, this would take the hinge out of play, put all the stress at the front of the bar and act as basically a rigid crampon. Flexible boot + rigid crampon = broken gear.

No, the hinge is at the front of the bar, but this is the bar at the back of the instep points, rather than the bar at the front of the instep points. It still flexes at the instep, but back by about a half inch.

I'm guessing its the flexible boots, although they are pac-boots. They just have a somewhat softer sole than most other pac boots, which allows them to flex too much for the crampon. Since I love my boots so much, I think I'll search for one of those shank inserts rather than buy a new pair. That way I can retain the other values of the boot and not sacrifice their flexibility when I'm not using crampons.

 

[jbrown]

No, the hinge is at the front of the bar, but this is the bar at the back of the instep points, rather than the bar at the front of the instep points. It still flexes at the instep, but back by about a half inch.

Ahhhhh, the fog is lifting... I re-read your original post and checked out the SMC crampons. I see what you mean, and I agree with your assessment that the hinge placement on the center bar is instrumental in the compatibility with various footwear, especially super-flexible boots like pacs.

The only way you'd have to worry about heat making them brittle if they were heated up high enough to change the grain structure and ruin the temper. Getting them cherry red and quenching in water will make them brittle, and if they get hot while sharpening them on a grinding wheel (way overkill) and are allowed to air cool they'll more than likely be alot softer than they started out.

 

[Umsaskis]

The old-fashioned solution was to buy an insulated steel-shanked insert from LL Bean and put it in the flexible boot which reduces boot flex and gives your foot much better support.

Where can you get one of these shank inserts? I couldn't find them on the LLBean website.

 

[bill bowden]

Steel shanked wool insulated inserts

When I got mine there was no mention in any catalog either. I was reading some sort of expose' of LLBean exploiting the poor people of Maine and it was mentioned as being necessary to make the bean Maine Hunting Shoe fit properly.

I called them and the operator was familiar with the product. the expose also stated that Bean's used smaller markups than most mail order places so I kept buying there.

 

[ken]

Here's an alternative for you: Kahtoola They're super flexible and made for any kind of footwear. The new steel model has 1" points. (I haven't used them, but have heard great stuff from people who own them.)

a guy on one of the hikes i was leading once had the aluminum version of the kahtoolas - i liked them.
i now have the kahtoolas in the steel version (i wanted them to last better) - nicest crampons that i have ever seen or used (and the shorter points make them nicer to walk in when you have to wear them all day) i don't know if the weight savings make it worth getting the aluminums over the steel, i doubt if you would even notice it (the steel will take longer to get dull and are still very light).

 

[Mike P.]

I'd look at the Kahtoola's also. I know people who tested these orginally & was out in December with someone who had them, For general use on trails they seem to work fine.

I'm not sure how they would be on water ice or steep hard windpacked snow I'd want to be on steep terrain, say Watson Path, Star Lake Trail.

If your boots don't have a shank, the Crampon MFG's would say they are too soft. Also the recalls from CPSC were for full crampons with front bails. When I worked at EMS (now 7-9 years ago) the recalls then were for front bails too. The Newmatics & Hybrids (back bail only which is more like a ski binding - from someone who does not ski) don't seem to have any issue providing your boot has a back platform for the hybrids.

 

[DougPaul]

i now have the kahtoolas in the steel version (i wanted them to last better) - nicest crampons that i have ever seen or used (and the shorter points make them nicer to walk in when you have to wear them all day) i don't know if the weight savings make it worth getting the aluminums over the steel, i doubt if you would even notice it (the steel will take longer to get dull and are still very light).

If he broke a steel crampon, I suspect that an aluminum crampon will break even sooner.

Doug

 

[RoySwkr]

You may be better off with a pair of crampons that have the hinge at the rear of the front piece, but then they might just break at a different place.

I have a pair of non-adjustable SMC 10-point with the hinge at the front of the bar, except that one of them made its own hinge at the rear of the bar :-(

These crampons fit my boot so well that the front piece stayed in place even though it was no longer attached to the rear and I was able to walk out on them. (Without lateral stiffness the rear part rotated to the side.)

I now have G10s but feel they are greatly inferior to the SMCs that broke - the metal pieces are thinner and there are fewer attachment posts to hold them in place if something breaks. Since I basically use them only for walking on slippery stuff they are OK, but I can't imagine real climbing in them.

 

[ken]

If he broke a steel crampon, I suspect that an aluminum crampon will break even sooner.
Doug

that's why i recommended the steel ones saying:

i now have the kahtoolas in the steel version ..... i don't know if the weight savings make it worth getting the aluminums over the steel, i doubt if you would even notice it (the steel will take longer to get dull and are still very light).