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Thread: Sharpening crampons

  1. #1
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    Sharpening crampons

    Anyone have first hand experience doing this? After losing 40 pounds and two years of use, my G10's are now losing traction on smooth glaze ice sheets with an incline > 20 degrees.

    Is there a good guideline for how sharp they should be for general mountaineering, and will an outdoor shop do it for you for a reasonable fee?

  2. #2
    Senior Member sierra's Avatar
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    file

    Use a file and do it by hand to avoid overheating the metal. A grinder would produce to much heat resulting in metal fatigue and failure in the field. Also dont over sharpen as some do, there is no need to have a knife type point, they will only dull faster.I always file towards the point end in one direction only. Hope that helps works for me.

  3. #3
    Senior Member DougPaul's Avatar
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    Ice climbers sharpen their crampons frequently, so any ice climber should be able to help you.

    To sharpen, use a bastard mill (hand) file (available at most hardware stores). Do not use a power grinder--it will overheat the metal and destroy the temper.

    Ice climbers may sharpen their points razor sharp, but a hiker need not keep them as sharp. Sharpness similar to the point of a ball point pen should be plenty for a hiker. You don't need them so sharp that they are at high risk of cutting or tearing your pants legs.

    Just looked up a picture of the G10 on the web--it is made of bent sheet metal. Sharpen the bottom points by filing on the edges of the sheet metal. Do not thin the sheet metal. (For the point under the ball of your foot, file the thin forward and backward surfaces, not the broad left and right sides.) This will shorten the triangle-shaped point slightly.

    I'm having difficulty finding a good image of the front points. If they come to points similar to the bottom points, sharpen them the same way (I think this is correct for the G10). Some crampons have a flat front point with the end shaped like a wood chisel. If this is the case, sharpen by filing the slant surface as when sharpening wood a chisel. The front points are less important than the bottom points for a hiker. (If you are on low angle ice, you should be "flat footing" rather than "front pointing".)

    For all your points, you might want to debur the points with the file. (This might dull them slightly.) Burrs tend to catch in fabric tearing one's pants legs or gaiters.

    Never heard of a shop sharpening crampons, but I suppose they could. If anything isn't clear about my description, you should be able to get advice from someone at a shop, or, of course, any half-way competent ice climber.

    Doug
    Last edited by DougPaul; 02-05-2005 at 01:39 PM.

  4. #4
    Senior Member Jasonst's Avatar
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    I sharpened my aluminum ones on a wheel. I am skeptical as to whether grinding steel crampons will alter the temper (if anything it should make the points harder and less likely to wear) Definitely leave a slight radius on the point.

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    Moderator Peakbagr's Avatar
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    I've been told by machinists and gunsmiths that the heat generated by a grinding wheel or Dremel will ruin the temper on almost any sort of steel. That will definitely make it easier to sharpen the next time, and ruin the ability of the steel to hold the point long.

  6. #6
    Senior Member giggy's Avatar
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    I just did my front points becuase I was climbing vertical ice this weekend and last weekend I beat the hell out them on mt washington with the rocks.

    This is my first year ice climbing so it was never really an issue when I was climbing moderate snow/ice - (ie hiking trails).

    what sierra said - is right on with what petzl told me.

    I called Petzl (who makes mine) and they said simply take a 6 to 8 bastard file for metal inch and go - They also said to file down (not up) the points in one direction - I hope that makes sense - its tough to explain.

    I have also heard from many people - do not ever use a grinding wheel or anything mechanical as the temperture will get way too hot and may damage the points. I think someone above said they use one - I wouldn't - better to be safe than sorry.

    Worked great - had no problems on the vertical ice - so must have worked. Took me about 15 minutes for the 4 front points.

    hope this helps. If you would like to phone me on how I did mine - PM me and I will give you my phone number. Probably easier to explain in words.
    Last edited by giggy; 02-07-2005 at 05:46 PM.

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    Jethro,

    I have just the solution. You should switch crampons with the Starchild. He is looking for shorter crampons and you are looking for sharper crampons. If you both switch, it might work out perfect.

    John

  8. #8
    Paul Skelly
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    Cool idea Johnnycakes!

    I am intrigued by this post... Would chrome-moly steel crampons, embrittled by poorly temperature-managed processing (AKA grinding) FAIL on the mountain?
    Unfortunately I couldn't say for sure either way. I've been surprised both ways in the past...

    First of all, in college, a friend and myself machined our own chain rings for our mountain bikes. We grinded into the wee-hours of the morning to get the profile necessary for smooth gear shifting on our respective rigs. The chain ring is still on my current bike.

    On the other hand, a well-respected welder in Pennsylvania assembled my Eastern Woods Research mountain bike frame in 1996. The frame failed at one particular weld bead that had been discolored by overheating during the assemblage.

    I am a little hesitant to believe that even a heavily embrittled steel crampon point would fail on the mountain. The loading isn't that great while hiking. But, as a scientist and amateur machinist, I would follow a process of sharpening a few points at a time, over several weeks and hikes, paying attention to the points when I get home, looking for cracks.

    Has anyone on VFTT had a crampon point shear off while hiking? I'm curious.

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    Senior Member DougPaul's Avatar
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    Steel crampons have been known to fail. They are frequently put down on uneven rock and a point may get caught in a crack and torqued. The metal can fatigue from the constant loading and unloading. Points can also be bent. Ideally, one puts the crampon down flat on relatively flat rock/ice.

    Destroying the temper by overheating the metal will just make a failure more likely.

    Flexible boots are particularly hard on crampons--rigid boots are best, but are harder to walk in. There was a recent report here or on the AMC BBS of a rigid connecting bar breaking (flexible connecting bars were available for the model in question). IIRC, the crampons were used with flexible boots.

    Doug

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    I had a front point break off while climbing Damnation gully. Fortunately, the climb was all snow that day and I didn't even notice until I got to the top of the climb. They were a pair of old Salewa crampons and had developed fatigue cracks underneath the bend where the front points attach to the frame.

    As far as temper and fatigue goes, it's obvious that there are no metallurgists in this crowd. Grinding crampon points will cause the metal to heat up locally but if done a little at a time the heat will be absorbed by the mass of the metal and you won't ruin the temper. You need to get the metal temperature up to several hundred degrees to ruin temper. If you do ruin the temper, that's called annealing and that doesn't cause the crampon to fail, but the metal will be softer and the points won't stay sharp as long after sharpening. If you heat up the front points way too much, they may bend if you're climbing vertical ice. In any case, it doesn't take more than a few strokes with a file to sharpen each point. It's quite a bit easier than sharpening a chainsaw. You should be able to look at the points of a crampon and see which surfaces have been previously sharpened at the factory. Just keep the same angle as the original when sharpening.

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    Quote Originally Posted by Jasonst
    I sharpened my aluminum ones on a wheel. I am skeptical as to whether grinding steel crampons will alter the temper (if anything it should make the points harder and less likely to wear) Definitely leave a slight radius on the point.
    This is bad advice.
    You should NEVER sharpen aluminum on a grinding wheel because it results is small pieces of aluminum getting stuck in the wheel. As the wheel wears (its ionly stone) the aluminum will tend to grab the piece of metal being ground and rip it for your hands. I got this lesson from a professional machinist when I was caught grinding aluminum on his grinder.

    And temper is most definitely affected by the heat of grinding. It is easy to get the sharp tip over 500F as it can easily get red hot in the grinding process at the thin tip. I'm not talking razor thin. This can happen if the metal is ground with a 45 degree angle and held on the wheel too long. For me, when I made this mistake, the tip wore down very (after 5 hikes) quickly.

    And by the way, there may very well be metalurgist in this crowd!

    Goes to show you that anyone qualified or not can post.
    "I've been kicked by the wind, robbed by the sleet, had my head snowed in, and I'm still on my feet, and I'm still,...willin"

  12. #12
    Senior Member Jasonst's Avatar
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    Quote Originally Posted by John H Swanson
    This is bad advice.
    You should NEVER sharpen aluminum on a grinding wheel because it results is small pieces of aluminum getting stuck in the wheel.

    Goes to show you that anyone qualified or not can post.
    Not sure if this was a shot at me, but I never said that I used a GRINDING wheel. Infact, I didn't - I used an abrasive sanding wheel. You do have to be careful as to not overheat the metal, thus affecting temper (softening). For most, it would be easier to just use a file.

    BTW, as far as little aluminum pieces getting "stuck in the wheel" - that's why you "dress" the wheel. I work at a machine shop with professional machinists - FYI.

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    Senior Member spencer's Avatar
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    I love a good pissing match over qualifications! What fun...

    spencer

  14. #14
    Senior Member Jasonst's Avatar
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    Quote Originally Posted by spencer
    I love a good pissing match over qualifications! What fun...

    spencer
    Sorry all, wasn't meant to be a pissing match. I just consulted with my mechanical engineer brother in law and he said the odds of distempering aluminum crampons on a sanding wheel are slim to none. The fact is, that the wheel doesn't generate much heat, and you are basically "touching" the metal to the wheel and not leaving the points in extended contact with the wheel. To truly "distemper" you need to be up around 600 degrees, in which case the points would just bend and become malliable. I think I have effectively beaten this horse!

  15. #15
    Senior Member sierra's Avatar
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    breakage`

    jfb,
    I used to own for many years Salewa crampons as well. I was helping litter someone down the Shelburne trail once and broke 2 of the points as well, I think they where ready to break anyway but all that weight seemed to be to much. To bad they where great crampons for many years, now I use Peztel and seem to love those as much, the front points have a foward curviture(sp) which really aids in steep hard snow.

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