Core questions???

[Gecko]

Years ago when I was working at Flite our cores were 1/8" maple sections laminated together...we used 2-3 ski cores glued together and then shaped...made for a lot of work. Towards the end of my time there we started getting cores that started life as 1/2" sections of laminated ash and maple...These we often cut to add stringers of things like CF and Kevlar (BTW I wouldn't recomend Kevlar...). Anyway my question is how are wooden cores constructed now...are they still using ash with maple in stragetic areas (edges etc)? Is wet wrapping still done or has a better way been figured out

[Matt D]

I took this from the Prior website. Vertically laminated aspen, with maple along the edges. Wood is good!

[nils]

yes wood cores are mostly vertically laminated wood, but Hot snowboards uses skateboard like (horizontal laminates) wood.

What makes a lot of differences, like in the ski industry, is the quality of the wood.. a wood core can cost from 5 euros to 12 euros here, depending on what woods are used! Ash is definitely the best for snowboards/ Skis !

Nils

[Donek]

There are a lot of ways to make cores, but most manufacturers use OEM producers. We make our own cores as well as produce cores for a couple other manufacturers. Our cores are all bookmatched with an ash perimeter. This requires a lot more operations to complete the process.

When we OEM cores, it's pretty basic. We laminate 3/4in lumber into a block that is as wide as the finished core. We resaw the block into several cores on a sawmill. The individual blanks are then planed on both surfaces and drilled for the inserts. We then presaw the shape of the sidecut on a bandsaw and then taper the core on a special planer. The core is then pattern cut with a template cutting router bit. This is probably the most common procedure for making cores, but can have variations depending on cap or type of sidewall construction.

[NateW]

Are cores made flat, with the camber and nose/tail curvature coming from the mold and lamination process? Or are cores machined in three dimensions so they have camber even before being laminated?

I remember hearing about some company machining the camber into the cores but I forgot which company that was and have often wondered if that's the norm or the exception. Seems like it would be hard to do efficiently.

[Donek]

Cores are typically made flat and bent in the mold. The only company I know of making pre-cambered cores is Vokl. I'm not sure if it's done on all their models or just their high end stuff. Doing so generates more waste and requires a saw mill that can cut an arc or curve. Our mill could do this, but would require some modifications. Most mills for cutting cores would not have the ability to be modified in such a manner.

[Gecko]

it's kinda neat to see which direction fabrication went in the last decade. We made a few precambered cores...making them was easy, it was laying up the board that was difficult. Our cassettes always returned to fairly flat after pressing, we ended up putting shims under the waist which helped some but not enough to consider making another batch of cores. I know of one board from that run that is still snappy and has plenty of camber after a decade so it worked just not easy

[tigger]

...my Völkl renntieger lost its camber after 30-40 days of riding

[ARCrider]

I think so anyway. maybe someone will confirm this

[Donek]

Originally posted by tigger
...my Völkl renntieger lost its camber after 30-40 days of riding

The best thing you can do for camber retention is frequent hot waxing. It may even be possibly to revitalize your board by hotwaxing it. If you get the board quite warm during waxing, you relax many of the stressed that build up as a result of riding. Your camber will last longer and return to a certain degree on a board that has lost it.

[Randy S.]

Originally posted by Donek
The best thing you can do for camber retention is frequent hot waxing.

That makes no sense to me, but I'll certainly take your word for it Sean. One more good reason to wax regularly. Thanks for the tip.

[skategoat]

Sean:

If you can cut pre-cambered cores, is there any reason why you're not doing it? I realize there is more wood waste but I can't imagine that the raw material cost of wood is that big a deal.

Not trying to challenge you, just wondering if there is a design or business rationale for pressing the camber as opposed to cutting it.

[Gecko]

Originally posted by skategoat
Sean:

If you can cut pre-cambered cores, is there any reason why you're not doing it? I realize there is more wood waste but I can't imagine that the raw material cost of wood is that big a deal.

Not trying to challenge you, just wondering if there is a design or business rationale for pressing the camber as opposed to cutting it.

There is also the question of time...as he would be milling both sides of the core not just the top...also the board reacts very different when everything is set before pressing it is actually easy to end up with too much camber using the same molds...i.e. you end up have to use a flatter mold to acheive the same camber. this was great for our 200cm board as we were stretching our 180cm mold (inserting a spacer into the center), however not so good for the 180cm

[Donek]

Randy,

When you continually bend the board (revers cambering it), the base material creeps. The is similar to a pane of glass in a very old church/building. The glass will actually be thicker at the bottom because the material is still flowing. This creep in the base generates certain stresses in the material. By heating up the base and the other plastics in the board, you are releaving those stresses.

Why don't we cut pre-cambered cores?

The machine we have would require some modifications to do this. I'm not dying to do them. There is a significant amount of labor in producing a core block as well as quite a bit of lumber. Because of our bookmatching process we already loose more material than conventional processes. If we were to cut camber, we'd loose even more. In some cases this would ioncrease the material cost by as much as 33%. I have also seen boards some of my with 300 days on them with the same omount of camber in them as the day they were build. As a result, I see very little reason to make the investment. If it's not broke, don't fix it.