Official "Problems" Thread - For Those Times

a.badner · Post by **a.badner** » Sat Jan 08, 2011 4:34 pm

Okay, i think skibuilders needs one.

official "vent-ing" thread.

ok. here is the story. i put rivets at the tips of my skis for aesthetics. turned out to be a completely stupid idea because the tips slightly cracked open (not big enough to care, and to little to do any work on). I have been skiing on them for about three times a weeks every week since november. ( plus two trips to Lake placid, and Tremblant and the occasional urban rail with friends.)

Hypotheses is: Little amounts of water have been going into the skis and freezing ( i leave my skis in the garage when they are not used ) and the water was expanding leaving a bigger gap for more water to be getting into crack.

this causing an exponential growth in the delamination of the tips.

or the Fibonacci sequence. because the water and ice that was there stayed there. leaving it more like a 1,1,2,3,5,8,13,21.... kind of thing.

Conclusion : dont rivet your skis.

now. you turn :)

Brazen · Post by **Brazen** » Sat Jan 08, 2011 5:14 pm

Never release the pressure in your press after 10 minutes to "reposition" your cassette. Really. Not ever.

skidesmond · Post by **skidesmond** » Sat Jan 08, 2011 6:03 pm

No need to rivet really. If you're using a full wood core, ie no ABS/plastic sidewall, you need a little more TLC w/ the skis. Knock off the snow before storing the skis. Check for tiny cracks or mini separations to prevent further delams.

Yes little amounts of water or dampness that penetrates to the interior of the skis is always bad.

Take a look at a commercial ski. The exterior is almost all plastic of 1 kind or another and usually a cap construction that seals out moisture. They'll only delam through abuse or a very hard sudden impact.

Brazen - yeah I agree

, double check everything before pressurizing.

falls · Post by **falls** » Sat Jan 08, 2011 7:21 pm

Try to avoid laying up skis when you're dog tired!
Try to avoid becoming a ski builder in a country where the ski season lasts only 3 months and all base grinding service operates only in this 3 months also.
Don't leave your 2 pairs of unground skis at home when you drive into the big city. Why? Because you will end up parking 1 block from a ski store that actually is grinding bases while it's 35C outside in summer. You'll have lunch in a cafe right next door whose bathroom is up a flight of stairs where the door in the landing has a glass window looking into the workshop and the smell of hot wax is seeping under the door. You'll also likely go back slightly late to feed the parking meter to find you have a $60 ticket and still 2 pairs of skis unground at home

.
I like this thread!

skidesmond · Post by **skidesmond** » Sun Jan 09, 2011 5:40 am

Getting interrupted (phone rings, dogs needs to go out,...) once you start laying down epoxy. "All I need is 30mins of peace and quiet, is that too much to ask?, is it?..."

MontuckyMadman · Post by **MontuckyMadman** » Sun Jan 09, 2011 8:25 am

Why would depressurizing and moving the casette matter? We do it all the time. No prob.
Graphics meant for certain length and size skis are the bane of my existance.

knightsofnii · Post by **knightsofnii** » Mon Jan 10, 2011 1:14 pm

dont press bolts into your board. dont press anything into it, even a speck of dust, or a tiny glop of mold release can cause dents/bubbles

when routering by hand, pray first, do a happy dance, triple check everything, and take a deep breath, and accept that you still may fail. Failures result in neat "bottle openers" though

ptex sidewalls suck, come up with every excuse why you need to do bamboo sidewalls, and why they are better. ptex doesnt really suck i just hate it.

make sure all your material thicknesses match, or else you'll have voids and bubbles, your press will only squeeze down to the thickest part going across (if you have cat track style), so be wary of thickness of say how your tip fill matches your core.

clean everything, when everything's clean and you forgot what you've cleaned, this is where you start, clean it all again.

do not touch mold released anything, and then touch board parts, or parts of board parts, remove your gloves toss them then wash your hands and then put on another pair.

getting all this stuff dialed, then going to ride the board only to find out it sucks to ride, really sucks, proper tuning goes a long way and can make an awesome board suck and a POS board ride decent.

knightsofnii · Post by **knightsofnii** » Mon Jan 10, 2011 1:16 pm

ive re-pressed boards and they came out fine, sometimes our resin needs just an extra 5 min or so to fully kick, specially when the shop is colder.

Or if we screwed up a pressing, we've re-pressed older boards to different bends: camber boards to rocker, shorter tip/tail rise points, etc.

twizzstyle · Post by **twizzstyle** » Mon Jan 10, 2011 1:18 pm

knightsofnii wrote: when routering by hand, pray first, do a happy dance, triple check everything, and take a deep breath, and accept that you still may fail. Failures result in neat "bottle openers" though

ptex sidewalls suck, come up with every excuse why you need to do bamboo sidewalls, and why they are better. ptex doesnt really suck i just hate it.

Ha, man. I can't tell you how much I relate to both of these things

skidesmond · Post by **skidesmond** » Mon Jan 10, 2011 1:26 pm

knightsofnii wrote:....
when routering by hand, pray first, do a happy dance, triple check everything, and take a deep breath, and accept that you still may fail. Failures result in neat "bottle openers" though .....

.

Thanks for reminding me about a bottle opener project.

Brazen · Post by **Brazen** » Mon Jan 10, 2011 1:40 pm

So, when I released pressure and moved the cassette, the inserts at the tail lifted out...one of them didn't go back in the right place and got smashed into the core, moving it off center AND the insert smashed through the base material. Tah dah! That's why I said that )

MontuckyMadman · Post by **MontuckyMadman** » Mon Jan 10, 2011 10:05 pm

Binding inserts? We use tape to tape the cassette tight so moving it is no worry. The masking tape comes off easy when hot.

knightsofnii · Post by **knightsofnii** » Wed Jan 12, 2011 12:02 pm

we got tight enough tolerances that we gotta hammer the inserts in, plus we hammer them in thru some thin glass, but yea that's happened to us as well where loose inserts fall out, fortunately for us they DID go back in place, but other factors killed the early boards anyway.

oh dont use a dull router bit to cut base material, or else then u have to razor/sand all the burrs off. Keep a specific bit just for cutting base and it will last you a long time, when it gets a little worn just step the bit down a pinch so its hitting a different spot, if you can.

every time you have to sand or razor a lump away, you're gonna have an edge gap, if you gave your cnc guy lots of beers and are good to him, your templates are perfect too so you will have gapless edges. I finally built a board with hand bent edges with no gaps.

falls · Post by **falls** » Wed Jan 12, 2011 1:37 pm

here's a good one:
don't set your trim router bit too high on the template when cutting the base material so that it really only cuts halfway through leaving a frill all the way around.
Especially dont do this after hand cutting stencils to apply a base graphic with paint rollers before waiting 4 days for it to dry and be ready for building.

(this did however make me wonder about using thick base material and routing the recess for the edge teeth into the base material rather than the core - prob too much of a hassle to then have to sand and flame the recessed area again)

carlito · Post by **carlito** » Thu Jan 13, 2011 1:32 pm

Oh, I love this topic.

How about.... Count your squeegees. Nothing quite as fun as discovering a squeegee sticking out of the sidewall of board.

Or.... When using cloths at +/- 45 degrees, and cutting them out, make sure your cuts stay at 45 degrees. Especially as you continue down the roll. When your skis come off the press they look great. When they come out of the back of the car to get base ground, and its -15 centigrade, they are seriously twisted. WTF???? Where did this come from? Why does god hate me? What is coeffecient of thermal expansion? It is really hard to cut kevlar cloth accurately at 45 degrees.

I can sure agree with making sure the thickness tolerences are tight. Funny, glue seems to go everywhere, but if there is a difference in thickness, will the glue stay in the void next to the thick bit? What do you think?

There's plenty more, but for now, finally: Come up with a system. Doesn't matter what it is, really, to keep track of tip versus tail. Or with skis, right and left as well. Usually, you will catch the mistake before the press comes on and it is simply a huge pain. But eventually you could be saying: "That's weird. The inserts should be here..." or: "Why is there no sidewall at the tail?"

I love this stuff.

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Official "Problems" Thread - For Those Times

Official "Problems" Thread - For Those Times

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