TLT7 Cable Mods / Improvements

[MTPOW]

After breaking the long cable I am convinced that it can be replaced and strengthened (diy). In addition there is a way to modify the lower cable so that lower shell compression can be improved and the buckle is easier to close. I tried it already but it was way too effective. I was able to tighten it way too much (felt great on my foot) and the long cable broke easily as a result.

My goal in the end is to make the cables bomber and improve the skiing performance of the boot by improving security over the top of the foot and near the ankle.

I'd love hear and see anyone else's attempts and ideas.

This will be a summer project of sorts (slower due to virus) so check back for updates.

[MTPOW]

Got the initial materials spec'd. Looks like around $40 with plenty of extra material for trial and error.

The mod should allow for increased thickness liners because the long cable length can be increased to allow the buckle to close.

This would be pretty sweet because I could put something like my maestrale liners in the tlt7 and way better performance and warmth out of a really light boot.

[phattypowpow]

I have a pair of TLT7 Expeditions that I've pretty much given up on due to the ineffective/pain-in-the-ass lower buckle. If you can figure a way to make the foot hold better and improve durability, I'd love to see it.

[MTPOW]

OK so after fiddling with a boot a bit more tonight here is where I am at.

- It is definitely possible and not complicated to perform a diy long cable repair with 1/16" cable. No need to replace the whole buckle for $70 if you dont have the cash. The tough part is recreating the adjustable feature on the lower ladder. Adjust-ability is probably not completely necessary but it would be nice to have. My first idea is to thread a hollow steel or aluminum tube, run the cable through the tube and swag the cable at the terminal end. Over all the homebrew 1/16" cable will probably be fractionally weaker than the factory cable so I think I'll skip that and work on the thicker cable.

- materials spec'd for thicker cable mod:
- 3/32" extra lubricated 7x7 cable (strength rated double the 1/16") PN: 3450T12
- copper swags PN: 3897T23
- extension spring sock 0.188 OD PN: 9664k74, 9664k45 (two different IDs)
- I am thinking the larger ID will work better because the wire diameter is smaller so I may be able to jam it more easily into the current molded spring slots.
- Aluminum Rivets 1/8 Diameter various lengths PN: 97447A025, 97447A025

I'll leave some other components for the adjustable ladder feature mentioned earlier for after I get the basics dialed.

A few challenges are apparent:

1) will the larger spring route and fit where the smaller original was? I hope so. It might fit but could take some force or if it doesn't fit maybe its not problem. If worse comes to worse I think I can dremel out some material and then zip tie through the molded cuff.
2) the black molded piece where the cable leaves the boot low on the cuff needs to be drilled out (among other components) so that a metal collar inside that piece can to be removed. As of now I cant really tell what the purpose of the collar is (probably prevents wear on between plastic and cable) so I am going to discard it and hope for the best. Once it is removed, it seems that I can jam the larger spring (3/16 OD) in place, possibly all the way through the black molded piece. I think the spring will stay in place by friction but if not likely by an adhesive of some sort.

All this will make way more sense if you tear apart you own boot or when I get the parts and upload pictures of the process.

[rickybobby]

Is it possible to rivet on a ladder buckle for the instep cable? Then just remove the long cable and tubing.

[kuus]

Great idea...i blew out a cable on day six of skiing my new tlt7s (standing at the top of a line smh). Dynafit replaced the boot but i haven't skied them since due to lack of confidence.

Would love to see photos of your mod. Also, cody townsend posted a video on youtube today about the mods he made on the x-alp, not exactly the same but might be helpful.

[MultiVerse]

I wonder if it's possible to mod the TLT7 to something more like a TLT8?

I like the TLT7 but find the buckles stick out too far for a lot my pants. TLT7 transition simplicity is nice but a standard forefoot buckle wouldn't make much difference and the ski lock buckle on the TLT8 lies flatter.

[MTPOW]

Ricky - in that case i would suggest a maestrale or snowboard ratchet.

Kuus - photos after I get the parts in the mail.

Multi - Could definitely put ratchets on to be similar to tlt8 but I am hoping to preserve the typical function of the boot. Not sure how a standard forefoot buckle would work since its not an overlap boot.

[phattypowpow]

I would LOVE to see a ratcheted bucket on the instep, a la TLT8. In addition to being stronger, I bet it would offer much better hold. The thin TLT7 cable that winds all around the boot was not one of Dynafit's finer ideas. If anyone figures out a ratchet buckle replacement, my dremel is already charged up!

[Cocximus]

How about the maestrale strap? I have a pretty worn out instep strap on my on my mercuries. I was kinda concerned about finding a new one, but I think I will just replace them with the maestrale strap.

[MTPOW]

I should say first that the mods I have don so far are on a broken and unusable boot (spine). I am planning on performing the mod on a good boot tonight. I'll take some pictures of the process.

Initial TLT7 Mod has been a full success so far. I was able to fit a Maestrale liner in and produce greatly increased forefoot pressure without breaking the cable system by moving the furthest forward cable rivet back and near the other rivet. This mod is where the performance increase comes from. It may also end up breaking the short cable or the boot shell at the rivet attachment. I think the risk is worth it because the boot gets so much tighter over my foot and closing the forefoot buckle is way easier than before even while creating significantly greater pressure on the forefoot. The boot now fits well and feels like it will rip because the heel hold is way better.

The mod took about 90 minutes including some minimal trouble shooting. The only compromise so far is that I was not able to install the larger diameter spring around the cable. Instead the cable lays in its intended path with no covering. This will likely create significant wear on the interfacing plastic and I'll be interested to see how fast the wear occurs. I do feel that the boot cuff could be modified to accept the larger spring but it makes more sense to see how much wear is created over a few tours first. I will try to add the spring cable cover where the cable wraps around the outside cuff pivot though because it look like it will fit and because it looks like it has the most friction (and potential wear) of any point in the system.

The short cable will probably break especially because the boot is so much tighter now. If it does I plan on just replacing it with the same larger diameter cable with "eye-end roller swags" at each end. There may be a reasonable way to eliminate one of the two short cable rivets leaving only one but that may only increase the stress too much on the one rivet point.

Edit: I'll write up a process with pictures of what I did for informational only. I cannot recommend any of these mods because they likely increase the risk of boot failure and thus serious injury or death.

[MTPOW]

Performed the mods on a good boot. It seems to work pretty well. The boot is tighter even with the standard liner and it is way easier to close the walk mode buckle even with a thicker liner so it really seems to be a big improvement. I need to modify the walk mode buckle a bit to so that has a lower profile in walk mode. The plastic wear due to the cable / plastic interface is still a big unknown. I use these boots pretty rarely anyway so it may be a while until I get that sorted out. Moving forward I will be working on an adjustable version of the ladder. I plan to keep one boot stock and compare the two for at least one decent length tour(edit 5-28-20 not doing the side by side). Let me know if you are interested in more info.

[MTPOW]

I put the mod boot on side by side with the stock boot this evening - both with stock liners. The difference is night and day. The ease of closure and ease of achieving confidence inspiring security really allows the the original boot concept to work.

I modified the walk mode buckle and upper swage in order to allow a lower buckle profile when open (can post pics if interested). The modification may reduce the long cable strength at the upper swage but I am confident that it will be stronger than the original cable.

I will definitely be modifying the other good boot before skiing next. On the next boot I'll use bolts with lock nuts instead of rivets to close the cuff path and try a wire rope clamp on the ladder end of the long cable so that I can easily open up the boot to check for wear along the cable path. Looking forward, using bolts instead of rivets would have the added advantage of allowing an in the field fix of the long cable system which is only really an issue if the new burly cable system actually breaks. Something to ponder over the summer anyway.

[MTPOW]

Will definitely be adding a protective spring around the cable before touring. I can see some wear around the pivot just from wearing them around the house for a while.

[MTPOW]

I have been thinking through a number of options for the protective spring cover and have boiled it down to two.

Option one:
- Install two separate spring segments. One through the top cable guide - ending short of the cable path constriction. A second spring through the lower cable guide ending after wrapping around the cuff pivot. The spring portion just after exiting the lower cable guide as it wraps around the pivot will have to have its diameter reduced by extending the spring. This option should eliminate most cable / plastic interface at points of highest pressure. I wonder how much wear will occur along the not protected portions and whether it will affect longevity. I am not too concerned and think this would be a fine enough solution but it got me thinking.

Option two:
Install the spring all the way through (1 spring from upper cable guide to lower cable guide). Use a soldering iron or wood burner to heat up the spring so that it melts and molds itself into place in the standard cable path. It may be prudent to perform the same diameter reduction around the cuff pivot in order to minimize friction and wear at that location. This option will pretty well eliminate any cable / plastic interface wear and pretty well mimic the intended design and associated function of the stock protective spring. I messed around before fully committing and the concept seemed quite promising. In order the press the spring into place while heating it, I modified the tip on the soldering iron by grinding off the tapered point then adding a v notch in the end.

In both option one and two, walk mode may cause the spring to work its way out towards the lower ladder (not acceptable). The solution here could be; press fit or thread a stopper collar where the cable exits the lower cable guide or maybe just melt some plastic at the cable exit to function as a stopper. Now that I think of it, if the spring is extended and spring diameter reduced around the cuff pivot as described above the spring may not move much at all at the lower cable guide.

Once again I am aware that this is likely impossible to follow without pictures. I'd be happy to post some or answer questions, though maybe its more likely that no one will attempt any of this. Any how I think I am almost zero'd in on a finished build.

I cant stop thinking how stupid this project is considering how many other great boots there are out there. What makes it worth it is that these boots minimize ankle pain for me and they were 180 bucks on ebay. I am still pretty sure I'll at the end of all this I'll have a very high functioning touring boot with more power and more durable cable system... at which point I fully expect the shell to break somewhere else. I tend to have a hard time dialing back anyhow so in the end these boots don't stand a chance.