HB (Hansen Boards)

Document your personal work here. Show photos, movies, and share your secrets.

Moderators: Head Monkey, kelvin, bigKam, skidesmond, chrismp

Jonsn
Posts: 18
Joined: Sat Jan 02, 2016 1:28 pm
Location: Munich & Bregenzerwald/Austria

Post by Jonsn » Tue Jan 24, 2017 12:02 pm

I have good experience when constructing cores like yours in using two ash stringers running from tip to tail and place them where the binding screws go. Center and outside of the stringers is paulownia or fir. The short sidewall under the bindings is ash again.

For the taper I use a circular arc that is tangent to the narrow part of the core and ends in 45 degree angle to the sidecut. I would make the taper even gentler (larger arc radius), which also helps draping the fibres and topsheet in that area.

24Dave
Posts: 101
Joined: Mon Oct 03, 2011 2:14 pm

Post by 24Dave » Mon Jan 30, 2017 6:05 pm

Thanks for the share. I had a similar break in a full paulownia core, (snowboard). Right between two reinforced areas. Strangely I have another board with the same lay-up but with veneer, and the veneer has prevented the topside from buckling. So maybe I would not only feather out your binding area reinforcements but also extend veneer a bit further and make the taper more gradual. (I mean don't have the tapered core as abrupt or right next to the rigid binding plate)

Bottom line though, a full Paulownia core asks a lot from the composite not to buckle in a deep bend. It just crushes fairly easily. I've thought about maybe a 2mm inlay of hardwood but will probably just stack more unidirectional composite with long tapers in the risk areas.

It's wild how the fracture in the carbon cloth runs up and down on the 45 axis as it crosses the ski. Oh I see, that is black basalt. If you can find it, Try a thin layer of Textreme over the Basalt and you get a real smooth finish without pinholes, looks really cool in the sunlight too.

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Akiwi
Posts: 370
Joined: Thu Jan 15, 2015 7:48 am
Location: Olching (Near Munich) Germany

Post by Akiwi » Fri Feb 10, 2017 8:41 am

Finished my replacement skis..
Core is different.. more Ash.
I'm not totally happy as I had some core shift..
I can still ski them though I think.. Will try them tomorrow.

Image
I am nobody. Nobody's perfect, so I must be perfect.

pmg
Posts: 435
Joined: Sat Dec 01, 2012 8:59 am
Location: Sonthofen

Post by pmg » Fri Feb 10, 2017 12:27 pm

Hi, they still look nice! Did you use the dovel method to keep the core in place?

SleepingAwake
Posts: 123
Joined: Mon Oct 11, 2010 11:06 pm

Post by SleepingAwake » Sat Feb 11, 2017 3:27 am

They certainly look good! I have no idea how you make that many skis in such short amount of time!

gav wa
Posts: 370
Joined: Tue Feb 18, 2014 8:58 pm
Location: Perth

Post by gav wa » Sat Feb 11, 2017 6:34 am

Dude! Awesome looking skis, but man you gotta get that core shifting issue under control. What are you doing to align your cores?
I always reckon keeping those basic parts of building as simple as possible is the best way.

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Akiwi
Posts: 370
Joined: Thu Jan 15, 2015 7:48 am
Location: Olching (Near Munich) Germany

Post by Akiwi » Sat Feb 11, 2017 9:53 pm

pmg wrote:Hi, they still look nice! Did you use the dovel method to keep the core in place?
No, and that was my downfall.
:(
I decided to try without, as that was where the last pair broke. I realize now that I could have easily aligned my cores using blocks glued to my press as these skis have sidewalls in the middle.
I'll chalk it up to learning and make sure it doesn't happen again.
I am nobody. Nobody's perfect, so I must be perfect.

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Akiwi
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Location: Olching (Near Munich) Germany

Post by Akiwi » Sat Feb 11, 2017 9:55 pm

SleepingAwake wrote:They certainly look good! I have no idea how you make that many skis in such short amount of time!
I sleep awake. ;)
I am nobody. Nobody's perfect, so I must be perfect.

SleepingAwake
Posts: 123
Joined: Mon Oct 11, 2010 11:06 pm

Post by SleepingAwake » Sun Feb 12, 2017 12:16 pm

Akiwi wrote:
SleepingAwake wrote:They certainly look good! I have no idea how you make that many skis in such short amount of time!
I sleep awake. ;)
:D 8)

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Akiwi
Posts: 370
Joined: Thu Jan 15, 2015 7:48 am
Location: Olching (Near Munich) Germany

Post by Akiwi » Fri Feb 24, 2017 8:01 am

Another pair of skis finished..
This is an everyday on piste cruiser.
It is my first ski with a full sidewall. Normally I did a cap.
Also I stained an ash veneer green and airbrushed the graphics onto that
Then used a 2 component Matt clearcoat over that..

Image

Ash core 1.5 - 12 - 1.5
600 Triax & Carbon stringer layup top and bottom.
Fiberglass weave under foot.

Image

Image

Image

Result is very stiff.
But for on piste blasting that should be OK
I am nobody. Nobody's perfect, so I must be perfect.

burnside
Posts: 16
Joined: Fri Aug 05, 2016 8:54 am
Location: Brooklyn, NY

Post by burnside » Fri Feb 24, 2017 8:44 am

Such thin tips! Excited to hear how these ride.

Does you core extend all the way to the tip and tail?

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Akiwi
Posts: 370
Joined: Thu Jan 15, 2015 7:48 am
Location: Olching (Near Munich) Germany

Post by Akiwi » Fri Feb 24, 2017 9:16 am

burnside wrote:Such thin tips! Excited to hear how these ride.

Does you core extend all the way to the tip and tail?
Yes, the core goes right to the tip about 3mm short.
I changed to cap construction on the tip as I didn't want the core exposed where it was cut through the fibres of the wood. On the sides the grain runs parallel to the cut so it should remain relatively waterproof. On the end grain the wood would not be so water resistant, therefore I don't expose it there.
I am nobody. Nobody's perfect, so I must be perfect.

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Akiwi
Posts: 370
Joined: Thu Jan 15, 2015 7:48 am
Location: Olching (Near Munich) Germany

Post by Akiwi » Tue Mar 28, 2017 2:48 am

Here is a video of the skis in use.
They are fantastic to ski on.
Stable smooth and easy to turn.

https://www.youtube.com/watch?v=5Bn3rw8pTik
I am nobody. Nobody's perfect, so I must be perfect.

skidesmond
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Location: Western Mass, USA
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Post by skidesmond » Tue Mar 28, 2017 4:23 am

Nice carving!

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Akiwi
Posts: 370
Joined: Thu Jan 15, 2015 7:48 am
Location: Olching (Near Munich) Germany

Post by Akiwi » Tue Mar 28, 2017 11:58 am

skidesmond wrote:Nice carving!
Thanks.. It was difficult picking my way through all the people. But I found a way ;-)
I am nobody. Nobody's perfect, so I must be perfect.

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