Inserts

nate · Post by **nate** » Thu Dec 10, 2009 8:16 am

I have 7mm inserts. My core is going to be more like 10mm underfoot. Should I countersink them so that they're flush with the top or flush with the bottom of the core. If flush with the top should I make some sort of filler underneath them?

Thanks

doughboyshredder · Post by **doughboyshredder** » Thu Dec 10, 2009 8:32 am

flush with the bottom. You want as much wood as possible between the flange of the insert and the top of the laminate.

nate · Post by **nate** » Thu Dec 10, 2009 10:05 am

Thanks. That's the way I would have assumed, but the skibuilders.com tutorial said the other way.

CFO · Post by **CFO** » Wed Apr 07, 2010 1:13 am

Hey Nate,

How are you going to clean the inserts out if they are buried in the core after pressing? If you are using a countersink, won't you hit the core on the way?

doughboyshredder · Post by **doughboyshredder** » Wed Apr 07, 2010 7:16 am

Ideally you would just use 9.5 mm inserts and flush them with the bottom

knightsofnii · Post by **knightsofnii** » Wed Apr 07, 2010 9:37 am

do what doughboy said but then when opening them up, try to do it with a drill bit the same size as the insert, you'll want to countersink as little as possible as it will leave you with a volcano crater looking hole if the inserts are in that deep. It's more difficult to get it perfect though with a drill, and i dont know how well the camax magnets will work if they're in deep. And yea you might want to pack the holes with wax or something to fill the gap to keep from getting topsheet/glass bubbles during pressing. Even though you'll only be removing this material anyway.

Then give them all a shot of laquer spray or something maybe which might protect whatever insert holes you do not use. Do you use all of them in a ski?

nate · Post by **nate** » Wed Apr 07, 2010 11:49 am

I'm not sure I completely understand that question, but I'll give a shot at answering it anyways.

Basically I drilled a hole all the way through the core for each insert. I made it big enough for the neck of the insert to fit through. Then I drilled a bigger hole on the bottom side of the core just deep enough for the flange of the insert to sit in. Then I jammed the inserts in, did the lay up, pressed the skis, ect. Finally, I just drill down from the top through the topsheet, the fiberglass, and any built up resin in the hole till I got to the insert, which had a cap on it.

knightsofnii · Post by **knightsofnii** » Wed Apr 07, 2010 12:59 pm

so you've already done it? how does it look? is there a lot of the inner layers exposed?

knightsofnii · Post by **knightsofnii** » Wed Apr 07, 2010 1:00 pm

my bad, this is old stuff, did it come out good? did your screws reach in the inserts fine? Yea the more meat you have between the flange and top of core, the better off you are.

nate · Post by **nate** » Wed Apr 07, 2010 3:45 pm

Yea, it came out just fine. I smeared some epoxy over the raw wood inside the hole to be safe, though it probably wasn't necessary (I left the sidewalls raw and skied them hard all season with no (few) problems. Which is not to say that it's best to do that.) I did have to get a tap to clean things up after that bit of extra epoxy since a little got into the threads. But I was pleased with how it came out.

nate · Post by **nate** » Wed Apr 07, 2010 4:04 pm

I see I missed a couple posts when I was answering questions.
Yea my screws reached fine, though I had to get somewhat long ones. My bindings are mounted on aluminum risers.

Like these. I come from skiboarding where inserts are the standard for mounting bindings. So I instead of buying new bindings for my skis I decided to just use these bindings I already had. Save money plus I can just move them back and forth. I just used 4 inserts per ski spaced 4cm by 10cm lengthwise.

I used a clear topsheet so spotting the inserts was no problem. I just left the space above them void in layup, but it didn't really leave any weird craters or anything after pressing. I open them I drilled once with a bit the same size as the insert and chamfered the edges of the holeswith a bigger bit. (kinda like a forstner, but beveled)

I did have a bit of trouble throughout the season with the screws stripping. The screws liked to work their way loose without my knowledge, even if I made sure they were tight at the beginning of the day. Once the screws got loose it didn't take much to strip them clean off leaving me with the binding and riser still on my foot but the ski leaving without me. A very bad situation. I should have learned the first time, but it happened once or twice more before I finally smartened up and bought some lock-tite.

I think that covers most of my experiences with inserts.

knightsofnii · Post by **knightsofnii** » Wed Apr 07, 2010 6:23 pm

were both M6?
I've never used loctite but the screws i've gotten either had a little paint, or had a plastic strip inserted into them to keep them tight, though periodically i still have to tighten.

nate · Post by **nate** » Wed Apr 07, 2010 6:27 pm

Yea everything was M6-1.
I was great after I put in a little locktite. I think part of the problem might have been tightening them when the skis were inside and warm, then going out into the cold.

CFO · Post by **CFO** » Mon Apr 12, 2010 12:21 am

hey Nate,

Yeah, I was just worried about exposing wood core when drilling down to the inserts after the layup. I have had a few boards pressed with inserts slightly shorter than the thickness of the core and when countersinking them during finishing process, the core got exposed and it was not a very good look.

nate · Post by **nate** » Mon Apr 12, 2010 2:48 am

Well. The core is exposed, but the hole I drilled only big enough for the screw to go into. So with bindings on you never see the holes.

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Inserts

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