Binding Screw Depth?

[Griz]

Like lots of dudes, I enjoy learning how to do things myself - even when its probably just as easy to let the shop do it for me. This summer I've been messing with binding mounts, making homemade jigs with plexiglass, etc... And, I've been drilling all sorts of holes in old skis practicing my work.

I think that I've got the basics down - meaning placement of the holes in relation to boot midsole, etc... but, I just wanted to double check my understanding of the screw depth. Particularly for bindings that have never been mounted - aka I don't have any skis to check how deep the bore was.

So, I read this thread: http://www.tetongravity.com/forums/showthread.php?t=65951&highlight=binding+screw+depth

It sounds like most screws need to go in about 7mm? If I make a jig to limit the depth of the drill-bit penetration, should I make it 7mm or closer to 9.5mm? Or is it really going to vary from screw to screw? And if so, how do I accurately determine the drill depth for bindings straight out of the box?

[pechelman]

depends on the ski
some skis like DP have to be drilled shallower
same with Spats because theyre so thin.

Other skis like wood core skis which are really thick can take 9mm no problem.

Skis with metal topsheets can generally take a larger diameter hole without problem because of the metal.

in the end though, it depends on the ski, the ski thickness, and the protruding length of screw. 7mm is enough for a good purchase, 9 is "better", and anymore than that isnt really needed.

most accurate way to determine depth out of the box is to put the screw in the binding hole, measure how far it sticks out from the underside of the binding, and drill that much AFTER checking that the ski is thicker than that measurement.

[Voltron]

Save yourself some trouble and get yourself some ski specific drill bits. 9mm works for the majority of adult skis. As stated though, check with the manufacturer for exceptions (Volant).

[SafteySquad]

So I'm gonna bump this old thread instead of making a new one about the same topic.

Do I really need to drill the whole 9mm? I have some s900's and when I put the screws into the binding holes, they only stick out of the base of the binding about 7mm. I read an old post by Conundrum and he said to have about 4 or 5 threads sticking out and all the screws have 4 threads, some have 5.

So should I drill the whole 9mm depth, or should I not drill the whole length of the bit since the screws won't ever go down that far? Or do I need a new screw set that goes the whole 9mm? I'm mounting up my Praxis, and they are pretty darn thick skis under foot, I measure 14.5mm with my calipers.

[DropCliffsNotBombs]

Use a 9mm depth for 99.9% of adult skis. Adult binding screws penetrate the ski 8mm, kids binding screws go 6mm into the ski (that's the standard). You need that 1mm of extra depth in the pilot hole so the screw doesn't push on the bottom of the hole and dimple your bases. Get real ski bits. They are cheap.

[Conundrum]

Use a 9mm depth for 99.9% of adult skis. Adult binding screws penetrate the ski 8mm, kids binding screws go 6mm into the ski (that's the standard). You need that 1mm of extra depth in the pilot hole so the screw doesn't push on the bottom of the hole and dimple your bases. Get real ski bits. They are cheap.

Word. My 4 to 5 threads statement meant at the minimum.

[Core Shot]

Save yourself some trouble and get yourself some ski specific drill bits. 9mm works for the majority of adult skis. As stated though, check with the manufacturer for exceptions (Volant).

Oh man is that true.

Many many years of mounting teles, and then rando skis with a drill bit and duct tape.

Finally spent $12 for a ski bit, and I can "drunk drill" my skis without worriyng about punching through. Best twelve bucks I spent.