Randonnee racers frequently Swiss-cheese their boots with a bunch of speed holes to drop weight. While I don’t really qualify for such modified gear (nor a lycra race suit), it’s fun to play around and see what works. Also, we’ve been known to do a bit of weight reduction on our ski mountaineering boots as well — something I feel much more deserved of as I need all the help I can get.
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One thing I learned from automotive work is that making larger speed holes is better than boring a bunch of tiny ones. Also, drilling plastic with a common twist drill makes a ragged hole that looks crummy and can wear out liners as they rub against it. For cutting a clean hole the tool of choice is a step bit, as shown in the photo above.
We’ve found it helps to first do a layout with ruler and Sharpie, then drill starter holes on the layout, using a sharp twist drill around 1/8 inch diameter. Then punch out the holes with the step bit. Racers also lighten their boots by grinding off a bunch of sole material. Key with that is working outside so the toxic dust isn’t an issue, and using water mist to keep the material cool as you grind (use a disk grinder with course open grit sanding disk). Rig up something to hold the boot firmly as one slip with a disk grinder can ruin an expensive pair of shells. Step bits are available at most hardware stores. If you need to punch a hole in automotive plastic (such as when installing an electronic device on your dashboard), they work nicely for that as well. They’re expensive but last forever if you’re only drilling plastic. There you go — Friday’s gear tip. |
9 comments
Nice holes Lou…
Now about that suit. I happen to have a men’s medium Crazy Idea one-piece (neon green & grey) that would perfectly match those F1’s and will trim your time at JH by at least five minutes. 🙂
And where exactly do you recommend putting these holes, in general, such that the integrity of the boot is not significantly compromised?
Could you collect and weigh the plastic debris to chart the actual weight reduction?–perhaps the same graph could compare gear weight reduction to calories burned (or saved). Sounds like a good
study for a masters thesis. LOL
How about cutting intricate designs with a coping saw instead of round holes. Grab a case of Pabst and see if you have any boot left at all at the end of an evening…
-M
Chris, I’d recommend evaluating how your boot performs while you ski it, then experiment with holes in areas that don’t need to provide as much support. For example, the holes shown above are bored on the top of the cuff, outside, as that area has less stress than others while skiing. Nonetheless this is PROCEED AT YOUR OWN RISK!
I’ve experimented with this quite a bit and a boot that’s used for moderate touring or racing can take a lot more drilling than you’d think, but if you buckle down tight or ski hard, the shell could crack if it’s drilled.
Hey wolfy, do the shells up right and use them in place of pumpkins on Halloween!!!
You making many rando racers nervous Lou…
…especially the night before a BIG race!
one suggestion is to use a wire brush disk instead of a standard grinding disk to remove rubber from the sole. Quicker, easier to clean up & no toxic smoke + it leaves a bit of a texture which can provide limited traction.
I took ~.4 lbs. of rubber off a pair of T2s (same size boot as the F1), leaving enough of the sole to still work in tele bindings
(I did not grind the front 3″-4″ nor the back 2″ of the heel, only thre arch of the boot). Be careful of removing all the rubber down to the hard plastic, while traverising an exposed slope last July 4th I slipped on a rock, the hard plastic does nothing for grip. It’s a good idea to leave a thin layer of rubber on the boot for that reason.
If you do take the arch down to the plastic you can add some Seam Grip to the textured plastic to reestablish some traction in the rocks.
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