3.6 vs 4.1 drill bit

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Woodserson
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Re: 3.6 vs 4.1 drill bit

Post by Woodserson » Mon Nov 05, 2018 7:24 pm

dnt_upton wrote:Maybe then it's due to what Atomic calls the "ultra-lightweight carbon insert that runs the length of the ski like a stabilizing backbone." In any event, I see no harm in using the 4.1 bit.
OOoooooh that sounds super techy and futuristic. They must be good now! "Stabilizing backbone"... wowzer!

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Lanomohym
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Re: 3.6 vs 4.1 drill bit

Post by Lanomohym » Fri Nov 30, 2018 2:17 am

I mounted my own bindings recently (swap meet stuff) and had a local
shop function test the bindings.

After I did some reading....I found that I was supposed to use a 4.1mm
drill bit and tap through the metal (aluminum?) sheet that runs through
the middle of my skis. I only used a 3.5mm bit and didn't tap.

what's the worst that can happen? realistically?

is it worth pulling the binding re-drilling and re-tapping? will that
make it worse or better? what's the benefit of using the 4.1mm bit?

or maybe it's better to buy new and expensive? I often play online casino real money, I choose them here https://casinos-advisor.com/ and can buy good things.

thanks...any advice appreciated and I won't sue anybody if my skis
explode.
Last edited by Lanomohym on Mon Nov 30, 2020 2:21 am, edited 2 times in total.



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fisheater
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Re: 3.6 vs 4.1 drill bit

Post by fisheater » Fri Nov 30, 2018 8:34 am

What happens when you do not drill out with a 4.1 millimeter bit, is the screw either cuts or deforms that .5 mm, which is really .25 mm per side. Now consider a millimeter is 1/24.5 of an inch, and I am going to call it 1/25 of and inch. That makes .5 mm 1/50 of an inch, and .25 mm per side 1/100 of an inch. I do not find these numbers to be significantly out of tolerance.
If I was mounting skis professionally I would always be by the book. However, I mount skis for myself, or help friends. I have never even used a metric drill bit.
Lastly, there is no benefit to pulling screws. The metal sheet has already been cut and or deformed. The screws I will assume, turned into the ski firmly. I am also assuming that the metal sheet did not delaminate and erupt thru the topsheet creating an uneven mounting surface. If that happened a sharp chisel could plane the topsheet. So other than the possible bubble, which you would have noticed tightening screws, you should be good. All the screws are securely tightened. Not building a skyscraper, so don't make Chinese arithmetic out of it.



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Re: 3.6 vs 4.1 drill bit

Post by phoenix » Wed Dec 05, 2018 11:29 am

All the above posts sound right to me. I'll simply offer a current summary and opinion, which echoes the previous post. I believe the 4.1 recommendation is due to the possibility that a 3.6 hole might result in the screw "crunching" the fiber, rather than cleanly threading the screw.
Tua (RIP) also recommended a 4.1 for their wood core/glass wrap construction.

It's probable that the 3.6 will be ok - but that's a probability, not a promise. One more bit isn't much of an investment relative to the rest of one's gear, and can be cheap insurance and/or peace of mind.



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t-$
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Re: 3.6 vs 4.1 drill bit

Post by t-$ » Wed Dec 05, 2018 5:24 pm

you guys are great.... i thought it was 1/4"??



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