Field repair of pulled bindings

As a tele skier, folks are always telling me that I've got a few screws loose.  It's all very curious, since I check them regularly...  

And Marcus, I've got the white, flat deck Insanes and I've been watching them closely. 7tm Tours, 3.5mm holes, Titebond wood glue, firm hand. I hope they never budge cause I like those skis a lot.

Good ideas here.  This is what these forums are all about.

-Dave

And Marcus, I've got the white, flat deck Insanes and I've been watching them closely.  7tm Tours, 3.5mm holes, Titebond wood glue, firm hand.  I hope they never budge cause I like those skis a lot.

That's the EXACT ski and set-up that did it to me. I was skiing them with T1s and both tearouts (original mount and helicoil repair) were while skiing inbounds (second run and first run, respectively).

I changed up to Insanes with inserts and used an adapter between the deck and the 7TM binding with good success for a while. Have since moved on to the NTN on that ski with no problems, but the NTN mount (frame breakage aside) is pretty beefy.

Why would wider, lighter skis be a factor? Lighter wouldn't in my mind except that they may not have the metal layer in them to help and the wood could be lighter. Wider, maybe more torque on the ski?

Wider = longer lever when edging or bashing hard stuff.  And, yes, some lighter cores exclude metal or carbon binding plates.

zeno published results of extensive pullout tests on ttips.  I recall that an ABS screw in a grossly oversize hole filled with epoxy had a pullout strength similar to that of a properly torqued screw in a proper size hole.  Of course, that might vary greatly across the range of different core construction.  zeno also acknowledged that he was testing pretty fresh stuff and his tests did not take fatigue factors into play, nor did it test for forces other than tensile. Most ski binding screw blowouts involve some shear forces. zeno's tests are nonetheless the best data I've seen.

ron j, that Mr. Grip stuff looks interesting.  Many people stuff fiberglass or steel wool with epoxy in a blown out hole

I've killed bindings 5 times in the last 5 years. Only once have I actually ripped the binding from the ski (that was a DH binding in bounds). The other 4 times the AT binding has failed at a pivot or other weak point.

I though I'd read about a surprisingly high number of people having had problems with dynafits ripping out of K2 skis. A ski partner had that happen last year with coombas that had only been skied on a few times. I think there's a thread on TGR to this effect, but i'm feeling lazy so you'll have to search yourself.

bottom line as with biking, motorsports or anything mechanical:
expect failure to happen.

Last January I got to chase after a friend's Manaslu after his Dynafit toe piece ejected from the ski -- the screws were still firmly attached to the factory inserts -- but the inserts had separated from the ski.

I like Lowell's hose clamp idea -- simple and straightforward and less work than boring holes through the ski for T-nuts and a better chance of a successful home repair of the ski afterwards.

I though I'd read about a surprisingly high number of people having had problems with dynafits ripping out of K2 skis.  A ski partner had that happen last year with coombas that had only been skied on a few times.

No doubt about it: some K2 cores have soft spots.  I hit so many soft spots on my AP's (Coombas with tele inserts, but I Dynafitted them) that I helicoiled every hole in both skis.  No kidding.  I've mounted several other Coombas/AP's/Coombacks and hit soft spots on every ski, some more than others, installing between 2 and 9 (all) screw holes.

But how many of us regularly check to see if all our binding screws are tight?

Me! And I check my bud's binding screws, tech boot fittings, Dyna rear fixture top sheet screws, etc., and I also retie rap runners, etc.