I prefer to mount my own bindings these days as I've seen/heard of too many issues with bubbled topsheets, pull-outs, crooked mounts, for/aft mis-positioning, etc. No doubt there are Pro Shops that do a great job and know what they're doing but ... there are always trainees. I do a bit of woodworking so have plenty of toys to help with the process.
I've never had an issue with three-screw toe-pieces on new or old skis pulling free, even on wooden skis, though I'd prefer four-screw mounts simply for the greater stability and reliability of that mount.
If you have any say in the mounting process for questionable skis - make sure the mount is done with proper drill bit size (just a hair larger than the shaft of the screw. I'd also make sure the screws are long enough after the useless tapered tips are ground off (if long enough, this lets the screws get in deeper with actual threads, but doesn't dimple the base).
I'd also ask for the screws to be set in with slow-set marine grade two-part epoxy. Care must be used when tightening the screws so as not to trap air bubbles below the screw (just have to tighten the screw slowly and reverse it a half turn once every full turn). I put it in the hole with a tooth pick then remove as much as possible, leaving only a thin layer behind.
Never over-tighten the screws as this tears the layers of wood fibers apart and 'drills out' the hole. The epoxy helps hold the layers together and bonds with the wood giving you a screw set in an epoxy/wood mix instead of just wood.
This mounting method works exceptionally well. I recently had an old Solomon Titanium heel-piece crack across the middle due to skiing hard on chunky ice. Guess it couldn't take the abuse. It broke 1/2 inch behind the front two screws giving me tremendous leverage against the back two screws of the heel-piece. I skied most of the morning only noticing the heel was making funny noises. At lunch, the brake fell off revealing the crack. I skied it for another 40 minutes and decided the last two screws might come loose if we went down the steeps, so got another pair of skis to finish the day on.
Taking it apart later I found that one screw was still solidly in place while the other had only just begun to slightly pucker and delaminate the top-sheet.
Note that marine grade plastic epoxy will not 'lock' the screws in permanently. It will just make the attachment/hold much more durable. A sharp twist of a screwdriver will easily 'break free' that hold and the screw will come out easily - just as if screwed into a nut. In fact, since the epoxy leaves a molded thread impression behind you can simply use a screw with the same thread pattern into the existing threads and it will still hold nicely (been there, done that - three or four times on this pair of skis).
I do agree: Three screws just isn't appropriate for modern gear. The skis are stronger and the bindings are stronger - so why isn't the connection between the two stronger? And with wider skis, why the heck are those mounting screws still only 1.25 or 1.5 inches wide? Even the wider bindings have narrow mounting holes. The edges of wide skis have much greater lateral leverage on narrow mounting screws than ever before. Maybe it's time to slap those industry Dilberts around?
.ma
