Heksu

heke · Post by **heke** » Wed Jan 20, 2016 1:53 am

I was thinking to build a short cat track and put it on top of the vacuum bag, meaning outside and put same weight on it to hold the tail & tip down. Cat track to equalize the weight, I have some 25 kg cement bags those could give quite equal load.

Akiwi · Post by **Akiwi** » Wed Jan 20, 2016 3:30 am

heke wrote:I was thinking to build a short cat track and put it on top of the vacuum bag, meaning outside and put same weight on it to hold the tail & tip down. Cat track to equalize the weight, I have some 25 kg cement bags those could give quite equal load.

I think that 2 pieces of wood rounded to approximately the radius of your tip/tail and somehow clamped down would be enough.

heke · Post by **heke** » Wed Jan 20, 2016 10:25 am

I roll the tail and tip to form of the mould. It looks much better now and bottom stays nicely in correct location in the mould.

What I also lean today is that if there is +23C inside and you take glued edges and bottoms from inside to outside -28C and to garage. Even in 30 seconds in -28C bends parts so much that there is new gluing work waiting. It was incredible fast reaction. Bottom was bended about 50 cm..like banana.

sammer · Post by **sammer** » Wed Jan 20, 2016 9:35 pm

heke wrote: What I also lean today is that if there is +23C inside and you take glued edges and bottoms from inside to outside -28C and to garage. Even in 30 seconds in -28C bends parts so much that there is new gluing work waiting. It was incredible fast reaction. Bottom was bended about 50 cm..like banana.

HA HA HA,

Ya, this has been discussed many, many times.
Base material is very heat sensitive.
The last thing I do before layup is cut out base and glue on edges.
All while attached to template.
I try to keep my work area stable 15-17c year round.
I'm sure if you were to search, you would find quite a few people who were surprise by this.
In a cold room you can put your hand on your base and watch it warp.

sam

heke · Post by **heke** » Wed Jan 20, 2016 11:08 pm

I found sollution..I will take two sleeping bags and move the parts inside it next time

I have also heat my work shop to prevent this problem when laminating.

What ever now the edges are better..

I need to measure if the base is symmetric or not. I have more base material & edges and I can make a new parts. I was thinking to build smaller skies as next so I can use the bases if those are bended or something.

Yes now I have read about the problem. This is not so easy.. it is difficult to search something you don't know existing... hopefully until now there is no errors that can not be fixed I hope..

Maybe by good accident I use double side tape to template and router when cutting the edges.

My work shop is very small.. so I can't store all parts there.

heke · Post by **heke** » Thu Jan 21, 2016 10:09 pm

Hi is there some one using hand plane to for wood core? I like to work with hand tools, some how the result is more personal, what ever difficult to explain..

I made the side wall rounding by hand, and remove some wood from tip part with hand plane, it was after machine plane maybe 0.3 mm too much.

heke · Post by **heke** » Sat Jan 23, 2016 1:54 am

Vacuum pumping with pump with oil. I have find quite fast that I need better one. It's really bad. Some moisture I coming out all the time. Good thing is that base and edges hold together. Temperature has rise here by 30 C..now it near zero. Yesterday morning -31C.

heke · Post by **heke** » Sat Jan 23, 2016 11:35 am

I have open vacuum..ski looks nice. Edge at very end in tail has move 1 mm, does not effect to anything. Veneer looks nice,2 I made only one ski..next will be better. I use heat 35-40C for 6 h and 75C for two hours. Use exactly 500g epoxy..half what I have.

Try to post some photos'.

heke · Post by **heke** » Sun Jan 24, 2016 3:59 am

Do you use belt sander to remove material from tip&tail? The plastic will heat quite alot?

For the veneer..maybe for next ski I put epoxy first to the veneer to make it softer.

heke · Post by **heke** » Sun Jan 24, 2016 10:57 pm

To keep the base & wood core together I use a wood pin glued to base material. Woud it work to make a round pin using waste of bottom material and make a small hole 4-6 mm to base material and to wood core. Repairing of the bottom is so easy that a small hole not a problem to fix.

I use double side tape to keep the base on mould, it work well.

heke · Post by **heke** » Sun Jan 24, 2016 11:40 pm

This is how it was after vacuum..

side wall

heke · Post by **heke** » Sun Jan 24, 2016 11:54 pm

Here is my heating cabinet. Made of insulation wood and duct tape.

Akiwi · Post by **Akiwi** » Mon Jan 25, 2016 1:37 am

Nice looking veneer.
Haha. your Heat box looks even more Ghetto than mine.

But the main thing is that it works.

heke · Post by **heke** » Mon Jan 25, 2016 7:09 am

I don't have much space, so heat box must be easy to disassemble when not needed.

heke · Post by **heke** » Tue Jan 26, 2016 9:42 pm

After heating in Sauna, there is 9 kW oven. Temperature is adustable between 40 - 110 deg C.
I don't know if after heating is needed or not but atleast with bamboo rods the epoxy seems to be harder after sauna treatment.

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