To add to the TLT5P mod-madness: My mod has been to significantly alter the cuff cant of this backcountry skiing boot and in the process build and install cuff rivets that rotate, stainless steel on stainless steel. When I took a brand new pair of these boots and ground out the cuff rivets, I was surprised to see that the boss that was molded into the lower shell was quite small and I suspected that if the rivet got sloppy at all that the cuffs would loosen up significantly, as has happened with many users.
Because there is no cuff cant and the boot and liner are such a slim and precise fit and do not allow for much lateral adjustability inside the liner, I needed to modify my cuffs to tilt them out about one inch. So, with the help of a machinist friend I made custom removable stainless rivets. One piece of the rivet is glued and pinned into the cuff so that it never rotates on the carbon fiber and the inside rotates against a large taper on the underside of the screw head. This piece has an OD of .85″ and an ID of .5″. I also pressed in a .0625″ diameter pin at 90 degrees to the cord of the OD and milled a slot in the cuff so that when glued in place this piece will never rotate.
For the inside of the boot I made a threaded piece where the center line of the thread is not concentric with the outside diameter. Then I turned this piece up on the inside of the boot and down on the outside of the boot (you can see this .5” difference in the close up photo) so that the cuff is truly canted. This was then glued into the inside of the shell. To keep all this tight in both longitudinal and rotational direction I also machined a bushing that rotates around the outside of the screw and on the inside of the outer cuff piece and sets the distance from the inside of the cuff to the outer side of the shell. This took some trial and error and the ability to machine small pieces in a lathe and milling machine.
I made a prototype with UHMW polyethylene first to see if I was on the right track and they might have even worked fine but I was afraid of breakage in cold temps. I also had to tilt the rear spoiler that locks the outer cuff to the inner cuff and re-bore for a slightly larger diameter; hence the stainless bolts in the rear that you can see in the photos. I put lots of miles on these last year and they’ve held up well. IMO, a typical cant cuff on one side doesn’t have enough adjustment and also only distorts the cuff and doesn’t truly cant it. I’ve never skied on a ski so flat in my life. When I wear these out, I’m definitely cutting the rivets out of them to use in another pair!
I like the idea of locking out the flex, but I don’t want to add rivets in the shell where they might cause some stress relief cracks. Your idea with the 16d nail is clever but I think it might just destroy the top of the mushroom head rivet (it’s very thin where it hits the nail) if used frequently. I’m thinking I might remove the one main central rivet and make an oval spacer to lock out the flex and then install a new rivet right through the center of it to permanently lock out the flex. I’m not sure that Dynafit got it right for the North American market to add flex to this boot. Doing so had to add considerably to the cost and complexity by adding three more molded pieces they didn’t need and also made the boot more susceptible to leakage.
The only other mod I’m going to make is to replace the power strap with one from the Maestrale boot; it is wider and stretches a bit. I seem to wear out the Velcro on the stock strap and it doesn’t have enough Velcro surface area to last very long.
This boot performs great in almost every way and fits my narrow long feet very well. If they improve the cuff rivets, offer an alternative forward flex piece, and also offer some alternative lasts for higher volume feet and to add warmth, they may just dominate the market in light AT boots.
(Wildsnow guest blogger Chris Marrone lives at the foot of Mount Shasta in California. He says he’s an “engineering/building contractor with a bad ski habit! He’s also managed the Sierra Club Foundation property and hut on Mt. Shasta as a volunteer for the last 20 odd years. You can go to his website to see the roof reconstruction that his outfit donated in ’04. It’s under the “public works” tab, “Shasta Alpine Lodge.”