Nov 11, 2008 at 5:16 pm #1231996
I've been working a few different designs over the last little while and just finished bending these ones up. Similar to the ULA ones…I think they were called Amigos?
I am still playing with the bend radius, and the metal actually failed in a few spots. I'll play around with heating it up and growing the rad to see what works best.
I'd like to make a version along the same lines as the microspikes but that will have to wait for some time off later next month.
They are made of 0.040" Ti 6AL-4V.
I do realize that for some of you, this would be somehwat useless for you, but for my neck of the woods it fits the bill perfect.
Weigh 62 grams (2.18 oz) each.
Cut the profile on the waterjet.
Crampon with straps.
Crampon and straps on scale.
Nov 11, 2008 at 5:32 pm #1458585
Steve, those look great!
Any plans for mass production?Nov 11, 2008 at 6:26 pm #1458599
> I am still playing with the bend radius, and the metal actually failed in a few spots. I'll play around with heating it up and growing the rad to see what works best.
I have done a fair bit of work with 6Al4V alloy. Heat it to a dull red or a bit hotter and it bends nicely. When it cools it is just as hard as ever! NO loss of temper.
But don't try to bend it cold: it WILL crack.
For further info read up on 'super-plastic flow' and titanium
CheersNov 11, 2008 at 6:28 pm #1458600
Suggestion: arrange for most of the strap under the foot to be between the metal and the foot. Otherwise the strap will abrade badly in the middle when you go over rock etc – and you will!
CheersNov 11, 2008 at 6:51 pm #1458604
@kennyhel77Locale: Scotts Valley CA via San Jose, CA
Judging by your photos, you should sell them!Nov 11, 2008 at 8:45 pm #1458623
Robert, no plans yet….I'm making 6 pairs for a few friends, but I learned a serious lesson with those ice axes. :)
Roger, thanks for the input, I was hoping you would reply.:) I remember you heated the ends of your snow stakes before bending the ends. I'll try heating it up later this week.
I had originally planned for the straps to end as soon as they entered the slots and then attach an anchor (plastic one maybe?) of some kind to lock them in place (think tying a knot in it so they no longer fit through the slot…so they only went around the foot, and into the slot but not underneath the crampon…I hope that makes sense?). After looking at how thin the straps were, and anticipating replacing them in the field if required, I though it would be best to have them run the circumference as they are now. I see your point, maybe I'll go back to my original idea, or add another slot to feed it through…
Ken, thanks for the compliment, but field testing should take place first! :)Nov 11, 2008 at 11:29 pm #1458638
@tallblokeLocale: DON'T LOOK DOWN!!
Nice piece of work Steve. I wonder if hard plastic grommets in the strap slots might save some wear and tear. Do the plates need to be 'full foot width' for a walking crampon? I'd have thought there would be less chance of spiking yourself or ripping overtrousers if the spikes were inboard a little way.
You have a PM.Nov 12, 2008 at 1:29 am #1458642
I would expect those to roll and yaw around the shoe quite easily.
Looking at your flat form, I would at least leave a bit of metal between the spikes and bend that up as you bend the spikes down.
To stop yaw you would need an upstand in each corner, which would mean rearranging your spikes.
The Kahtoolah's have the straps ending on these bent up tabs, that must be more secure.
I suspect that if you walk on ice uphill, as your foot drives off and the shoe flexes, at some point all the spikes will leave the ground and just at the end of each push off you will loose traction. Would it be better to make the front spikes a little longer? In one of your photos they do not touch the same flat surface as the side spikes sit on, perhaps they should?
Could you save weight by cutting a hole in each spike?Nov 12, 2008 at 1:39 am #1458644
> Looking at your flat form, I would at least leave a bit of metal between the spikes and bend that up as you bend the spikes down.
> To stop yaw you would need an upstand in each corner, which would mean rearranging your spikes.
Good points imho.
> The Kahtoolah's have the straps ending on these bent up tabs, that must be more secure.
Another variant has the bent-up tabs, with slots, and the webbing zigzag backs over the top – one long length. Fixed bail around the back – Tri_Glide maybe.
CheersNov 12, 2008 at 7:00 am #1458660
Further thoughts Steve,
I think the slots you have threaded your straps through are in such a place as to weaken the side spikes. I think you will get stresses emanating from the ends of the slots that may snap off a spike. I am thinking of twisting and turning on hard frozen surfaces or rock.Nov 12, 2008 at 8:20 am #1458670
@thomdarrahLocale: Southern Oregon
This looks very nice, you have done a great job – again. Your Ti Walking Crampon makes my modified summer crampon seem silly and very very heavy (see my "MYOG: Summer Crampon" post of 6/26/08 with pictures).
I had simply removed the binding/crampon from a pair of MSR snowshoes for use when crossing early season snow sections. My idea could be ligthened alot with some effort. The best feature of my idea was the shoe attachment being very secure and durable. I just modified the use of an existing great product and can not claim any originality.
Again, great job and keep up the good work.Nov 12, 2008 at 3:45 pm #1458721
@redleaderLocale: Luxury-Light Luke on the Llano Azul
Now you have a whole lot more friends.
Evans Ti Ca Ice Tool #18Nov 12, 2008 at 5:14 pm #1458736
any long term test results?Nov 12, 2008 at 6:08 pm #1458745
They look great. Now when you make my paircan you make a slight mod?
The triangle of solid Ti just inboard of the slot looks like it is just about big enough to form a tri-glide buckle. If you water-jet a border around it and an extra two slots I envision it bending up into a vertical upstand, when you bend the spike down. (does this make sense?) This mod should prevent some of the horizontal yawing/sliding of the shoe on the top plate AND eliminate the strap under the crampon. It would mean redesigning the central plate a little, and I'm pretty sure that you won't save any strap weight once you thread through both triglides.
Any chance of making mine in red? ;^)
RodNov 12, 2008 at 8:58 pm #1458781
Roger T, the strap setup will have to be changed if I want them to last. Some deburring may go a long way, but not a permanent fix IMO. Grommets would be nice to minimize abrasion. The plates are just slightly thinner then my shoe width. About 1/4" on each side. I was trying to get away without making these adjustable for different shoe widths and figured they would hold better if the straps contacted some of the sole.
Derek, you may be right, I haven't used them yet so we'll see. Perhaps a different strap configuration would hold better. I wanted to add some tabs bent up, but there were some complications with that. The first is that I would then have to make them adjustable, and the second is that I only have a simple sheet metal brake and it is only capable of simple bends.
I do agree that the kahtoola is a superior design, and I plan on making a more robust crampon, but it is overkill for my upcoming trip which consists of mostly icey trails. The short ups and downs I'll be dealing with wouldn't be worth carrying anything more – I'll just adjust the crampon to sit at the front of the shoe and adjust my walk accordingly.
That being said, I am already well on my way to working on the next version…adjustable with all tabs. I'll post pics when I get around to finishing them.
Regarding your thoughts about the slot causing some weakness, again we'll have to see. I know that the ULA ones were suffering from this problem, but they were aluminum. I chose the 0.04" thickness because I calculated that it would take a 200lb direct side load to snap it off. That gave me a good idea of where to start. If it ends up being a problem, I'll move the slot.
Thom, I saw your crampons when I was searching a while back. I like them. Heavier yes, but they work and if you could remove them in the field, that would awesome. Shoe attachment was very robust. I need to work on my…obviously.
lk, no long term results…in fact, I have no results as I haven't used them yet! Still waiting for the snow and ice.
Rod, thanks for the compliment. I think I understand what you mean, but I don't think it can be done easily (definitely not on my machine) but I'm not a sheet metal expert. Cutting the triglide right out of the crampon is a great idea though. I like it and it simplifies the amount of parts I need to use…you've got me thinking! As for the color red, I cut out anodizing any of these things after the terrible results on the early version of the ice axe. I can paint it if you like? :)
So, would everyone prefer to see a ti kahtoola style crampon at a heavier weight? Just shooting from the hip, I would think it would be roughly twice the material so maybe 4 to 4.5 oz each.Nov 12, 2008 at 10:07 pm #1458796
Regarding bent-up tabs:
I have some old Stubai crampons from the 60s. To some degree they are the same as what is being proposed here. Take a flat sheet, cut out holes everywhere, bend the crampon spikes downwards and the strap tabs upwards. At the top of the strap tabs there were rings through which one long tape went. No slew, easy to fit, single buckle, …
However … My memory is that the crampons were fitted to my boots with a torch! The design idea was that you adjust the width of the tabs to suit your boot – red hot. The steel would take it. Hum … But it worked great!
CheersNov 13, 2008 at 3:06 am #1458802
my ideal would be a titanium crampon lighter, more flexible but as grippy as Kahtoolahs with a removeable, swing into place and lock front point, which rigidified the crampon for front pointing. I imagine this extra point either: off all together, fixed to the crampon but swung back behind the heel, or forward in place. Whether such a versatile system is possible and practical I do not know.Nov 13, 2008 at 8:18 am #1458819
@thomdarrahLocale: Southern Oregon
The MSR crampon/binding is very simple to remove in the field and are easily reinstalled. Removal is via four (two on each binding)cotter pins, just be careful not to misplace these or carry extras. Rock or hard ice could damage the attachment point on the binding making reinstallation onto the snowshoe difficult. I removed the MSR binding from a retired set of MSR snowshoes, and having no plans to reinstall, this for me was not an issue. Your ti crampons are much nicer (and lighter), hopefully the binding/strap concerns can be addressed.Nov 13, 2008 at 7:30 pm #1458895
Roger, good to know. I was thinking one strap and a buckle could be a good setup.
Derek…anything can be done…not sure if I'm up for that quite yet. :)
I didn't realize you could take them on and off. Very neat! When i first received my NL backcountry rescues I was thinking of a system where the crampon would come out of the snowshoe for uphill travel and such.
I'm making some revisions and going to heat these guys up before bending…we'll see how it turns out!Nov 14, 2008 at 4:12 am #1458909
I would have thought such a crampon as I imagined was makeable and I can sort of see the design; but I would be interested in anything near as good as a Kahtoola and significantly lighter.Dec 5, 2008 at 7:51 am #1462305
Had to get these bent up outside of our place. Even with heat applied, the bends were not looking too good…they DID look much better, but not up to an acceptable standard IMO. I'm getting the straps sewn up this weekend (I've employed my mom to do this!) and we'll see how they handle some abuse.
The bends really did turn out great.
Dec 5, 2008 at 8:00 am #1462309
@dsmontgomeryLocale: one snowball away from big trouble
Nice! Is that sheet thicker than the original?Dec 5, 2008 at 8:08 am #1462315
Same thickness, just a bigger bend radius, and bent on a proper press. Preliminary testing (walking on concrete in my garage) leads me to believe I may have to move up in thickness a bit. But my plan is to get the straps finished and go for a jog down my street. :)Dec 10, 2008 at 9:32 pm #1463598
I finished up the straps and gave these guys a little test. Conditions were perfect as it was pretty wet this morning and then froze solid this evening.
First off, I ran out of material for the straps so I had to make due with some green polka dot strapping my mom had lying around her house (she sewed them for me). Also, I thought i took some good pics, but they all pretty much stink – sorry.
They were a little finicky to get on, but once on they were great to walk in. I didn't trust them at first, taking it easy on the ice, but they gripped nicely and dug right on on the softer stuff. As I got comfortable walking in them, I thought they would start flopping around and such but they held well. Keep in mind that this is flat ground and the ice was pretty much flat aswell.
Being convinced that they were going to hold up on snow and ice, I took a spin on some sidewalks around my park. They were really noisy and sparked like mad (picture firecrackers coming off your feet) from the friction. I didn't want to travel too far/long in case someone called the cops or something (it was a quiet and pleasant evening :)).
Here's the best pic I have…teeth dug in nicely over thin layer of ice strong enough to support me without breaking.Dec 11, 2008 at 12:08 am #1463612
Those are looking great! Could you reduce the amount of metal remaining in the flat underfoot section? Not that it would appreciably reduce weight, but it seems that most of your rigidity comes from the perimeter frame, especially with the larger radius.
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