NTN Freedom + inserts - screw length? (paging tele.skier ... )

[ts01]

Has anyone mounted NTN Freedom on Quiverkiller or Binding Freedom inserts? If so what screw lengths are you using? It looks like tele.skier has done so (http://www.backcountrytalk.earnyourt...hlight=inserts) - anyone else?

I'm fiddling with NTN Freedom / Binding Freedom combo using flathead screws. First tried the 8mm length recommended on the Binding Freedom web page -- (http://www.techinfo.bindingfreedom.com/ ... _LD31.html). But it seems like not enough thread engagement - just a couple or three threads hang out of the bottom of the binding, and the threads wouldn't engage on one of 6 inserts in a test install.

So I picked up a couple of 10 mm, 12mm and 16 mm samples from the local hardware store - some flatheads, some buttonheads. 16mm is too long, 8 is too short, 10 and 12 both seem to work. Left to my own devices I'd go with the 12mm, on the "more is better" theory, but when I tighten everything down on all 11 screws maybe that would be too much....

Before the next trip to the hardware store I'm curious what other folks are using. Seems like a silly question but I'm a little thrown by the binding freedom recommendation seeming so wrong.

Thanks in advance for any feedback on this.

[tele.skier]

I use seven 10mm long screws on the actual binding. I use two 8mm on the pink plate that the binding claw sits on. I shim the heel up 1/8th inch, so I have to use 12mm on my heel piece. If you don't shim your heel up and bolt it right to the ski, you can use 10mm on your heel.

... a few things,..... First too long a screw is bad. I mistakinly threaded a 12mm screw into a binding hole and I "spun" the insert tightening it to the deck of the binding. I only realized it was an issue when I went to swap the binding to another ski and the insert turned right out of the ski rather than release the screw. I used a vise grip on the insert and removed the screw from it, allowing me to reglue it back into the ski... Note to self: Pay attention to which screws go where...

....also, I mount my threaded inserts so they are a full 1/32 lower than the ski deck If you leave your inserts a tad high by accident, the 10mm screws are very close to bottoming out. As I found out,... bottoming out a screw in an insert usually spins the insert in the ski and breaks the epoxy joint free, Then it is difficult to seperate the screw and insert that remain on the binding until you can unthread them. (I carry a mini vise grip and T wrench)

.... accuracy is very important with inserts. You don't want to have any screws that bind as you thread them, this will weaken that insert's bond to the ski. (trust me, it's very difficult to briefly explain why) I made a jig in the freedom pattern, which was time consuming initially, but makes drilling subseqent pairs of skis easier and predictably accurate.

I ordered my stainless screws from Mcmaster/carr. They came in hex head, so I carry a "T" handle hex wrench in my tool kit so I can check my binding screw torque quickly.

As I said in other threads. I like the inserts for NTN freedom so I can remove or add the brakes when I am touring or riding the lifts. I don't want brakes when I tour most of the time.

...HTH

main binding screw: http://www.mcmaster.com/#92095A208


pink guide plate screw: http://www.mcmaster.com/#92095A207


heel screw IF you shim it up 1/8th: http://www.mcmaster.com/#92095A210


I carry this "T" handle hex key to torque the screws: http://www.mcmaster.com/#5629A63

[ts01]

OUTSTANDING. Thank you. No doubt I'll make my own mistakes that others can learn from but this set of lessons learned is a great start.

"Bottoming out" concept means more is not always better. Who knew?

Pretty sure I'll have the inserts at least (if not precisely) 1/32" below ski deck - using a rotary file (kinda like the one in the center here: http://www.northerntool.com/shop/too...ct_39812_39812) to countersink.

For the heels, I have a spare set of Hammer Heels which I recall from TTips days were a workable replacement for the NTN Freedom heel that added enough height to compensate for the ramp angle issue that presumably led you to use shims. Since I'm mounting Freedoms on skis that previously were drilled for Freerides this will require adding only one hole for the heelpiece and I can save the heels that came with the Freedoms for another ski and not have to swap heelpieces. Make sense?

[tele.skier]

"Bottoming out" concept means more is not always better. Who knew?

If the screw bottoms out in the insert before the head contacts the binding, most people will "spin" the insert in the ski trying to get the binding torqued down... (I did it by mistakenly putting a 12mm screw in the binding where a 10mm screw is already close to bottoming out)

Pretty sure I'll have the inserts at least (if not precisely) 1/32" below ski deck - using a rotary file (kinda like the one in the center here: http://www.northerntool.com/shop/too...ct_39812_39812) to countersink.

I would just use a standard woodwork countersink. They work fine... no need for a rasp tool.

Place a 10mm screw in the binding and measure how much protrudes out bottom. That distance is close to the full inside depth of the insert,... SO either set the insert a bit deeper in the ski and use 10mm, OR use 8mm screws and get less thread contact... 8mm screws would probably work fine too....

For the heels, I have a spare set of Hammer Heels which I recall from TTips days were a workable replacement for the NTN Freedom heel that added enough height to compensate for the ramp angle issue that presumably led you to use shims. Since I'm mounting Freedoms on skis that previously were drilled for Freerides this will require adding only one hole for the heelpiece and I can save the heels that came with the Freedoms for another ski and not have to swap heelpieces. Make sense?

Hammerhead heels were simple perfection. If they are 1/8th" taller than the stock freedom heel, they would be ok... I don't expect everyone to have the same solution as I did to the low heel. Some people opted for more forward lean on their boot cuff, which has a similar effect, but gives a less energy efficient resting stance. It does counteract an overly verticle shin angle, which puts a skier's hips in the back seat.... which is the problem that the combination of low heel and a locked verticle cuff create, and the reason I shim the heel.

[ts01]

Thanks again.

One more question - do you use vibratite or loctite on the threads? My bike holds together with the threads greased, not thread-locked so it goes against instinct to apply that stuff.

[tele.skier]

Thanks again.

One more question - do you use vibratite or loctite on the threads? My bike holds together with the threads greased, not thread-locked so it goes against instinct to apply that stuff.

I use automotive grease myself. The grease allows you to get a truer feel for how much torque you apply to the screw by eliminating most of the resistance from thread contact. A binding's base plate needs to be under pressure with the surface of the ski, NOT riding losely on the shafts of the screws. A binding that can wiggle slightly side to side against the screws, will eventually rip out of the ski. This is one of the reasons that I like to paint a light coat of epoxy on the top of the ski, then bolt the binding down. The molded image of the binding that hardens on the ski top, helps resist latteral force when the epoxy dries. This takes some of the latteral force off the screws/inserts. IMO, Rip out is mostly caused by lateral forces oblonging and weakening the screw holes before the final upward force gives the killing blow... and rips the binding out. Most people see the result and think that latteral force plays no role in "Rip out". I remember this same scenario from when I skied 3 pin bindings, and the answer was the same,... Paint the ski top with epoxy so it cradles the binding base plate...

I have thought about using some saran wrap under my bindings to make that supportive epoxy cradle for my Freedom bindings on skis with inserts. It would take up the lateral force better and take some latteral strain off the inserts... Maybe I can research some liquid release agent that would also work that way.... or maybe 7 screws per binding don't need that sort of help so long as the screws are torqued....