project - crampons

DIY mountaineering crampons. Rough sketch, solidworks 3d design to get it laser cut out of Hardox 450 steel. Parts hand bent at the forge, manually hand filed for precision fit. Drilled and pinned using brass rod.

DIY step breakdown:

sketch out assembly, develop 3D CAD model for lasercutting
Heat to orange heat in the forge, bend all parts as needed, check level, upper support twists for webbing ring alignment
drill holes for brass pins
drill inner chamfer as needed for brass pinning, seating
drill holes for webbing rings
cut, grind and shape metal supports that will be pinned to crampon body
cut, grind, and file the connection bar and front trapped swivel mating area
pin the parts together
install kydex anti balling plates
install the rings
install webbing
local field test
determine whether heat treatment and tempering required

Rough size and outline quick sketch
3D CAD parts
Laser cut part, based on 3D CAD model supplied to lasercutting company
Details of the brass pinning. Curious to see how that will hold up. Those brass pins were a little short. I would have liked more material to fill the inside chamfer area fully.
Clean fit of the connection bar. I am still deciding which option to use, as a lock-out for the sizing connection bar.
Tracing out the basic pattern for the anti balling plates
Fitting patterns on a single sheet of kydex (note, don't use sharpie on kydex, it's porous enough to make it truly permanent).
Cut the kydex using a jewelers saw, heated it up and formed it around the crampons. There are some final adjustments to be done, as well as trimming and cleaning the edges.
Wanted to make sure the lacing/kydex additions fit nicely and still laced solid. The idea behind the anti-balling plates is that they're captured, however, there is movement. With every step, they will move and spring back into place. Hopefully making it more difficult for snow to accumulate.
Both crampons finished! Notice the tight kydex wraps around posts. Heat gun final adjustments were quite easy.
Detailed view of the eyelet for anti balling plates lacing. It's just there to restrict spring back movement of kydex below. Lacing is 550 para-cord with light reflective thread.
Detailed view of the cutout where the connection bar is captured on the front piece. It can move to fit different boots and angles.
Threaded a simple 10/32 cap screw through both pieces of metal. It's a nice tight thread, if it does work loose. I can loc-tite it into place.
Crampon laced onto the boot, front view
Bottom view. Once laced, they are surprisingly solid.
TODO:
-Field test, possibly remove kydex, file, sand and paint metal parts with rust inhibiting paint if the wax sealant doesn't protect enough.
-solder rings shut, or replace with round rings
-purchase a kevlar crampon carry pouch so I quit stabbing myself with them :)
Lessons learned: Spend more time simplifying the design in the CAD phase. Too much time wasted on simple things like lacing. Went for the simplest form. Could easily be updated to include cinching buckles.

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