flax composite stitch & glue

Originally Posted by magwas

It is a bit still tacky in some places after a week. I have cut it to shape anyway.
In some places the flax and the polystirol did not stick to each other. (first picture)
The flexibility seems to be adequate for doing origami, so I have started to sew it. (second picture)

Polystyrol???

You said EPOXY !!!

Where did you use polystyrol in that layup?

[magwas]

Originally Posted by apex1

Polystyrol???

You said EPOXY !!!

Where did you use polystyrol in that layup?

see post #23. you do not miss anything in this forum, eh?

Originally Posted by magwas

see post #23. you do not miss anything in this forum, eh?

Go play your game, don´t want to disturb you.............

over and out.

[zerogara]

Since you probably can not heat it in an oven expose it to sunlight. Although some epoxies are not affected by UV, if your mixing ratio is wrong it may not cure. What if you delaminate it since it is still tacky and relaminate with proper epoxy?
At least at the end you can say you learned something!

Originally Posted by magwas

I am trying to heat it with a hairdryer, but it is still tacky after 3 days.

Now I am off for a week. When I return I will continue the building, no matter what.
It is an experiment anyway

[magwas]

Sewing went too slow, so I have tried cellotape.
Half of the boat is roughly at shape, but it seems that the material was too floppy.

[magwas]

Okay, I am aborting this project.
1. The shape will never be anything like I want it, unless I do a lot of fiddling
2. The styrofoam came in roll, and the piece used for the other side (which is from inside of the roll) is just breaking when I try to flatten it back
3. Even if I try to assemble it with the already applied flax inside, the chines would need additional clothing, which would be very hard with this shape
4. flax did not glue perfectly in some edges

Maybe this technique could be appliable to a canoe (#3), with no sandwich or using styrofoam which comes flat (#2), and using more layers before attempting to shape it (#1), and using some flat wood panels for pressure while curing (#4).
I am not trying it right now.

I am thinking about whether to try to build my Luna design by laminating flax over a styrofoam mould. I would build the mould much like a stitch&glue boat, but of 20mm styrofoam, and laminate flax over it.

[uncookedlentil]

try vacuum bagging your layup over your mold for the next run and I wouldn't advise trying to reglue unfired epoxy at all.

Rome wasn't built in a day and the Wright brothers crashed a lot of airplanes. I wouldn't let a setback be too discouraging.

[magwas]

Originally Posted by uncookedlentil

try vacuum bagging your layup over your mold for the next run and I wouldn't advise trying to reglue unfired epoxy at all.

Rome wasn't built in a day and the Wright brothers crashed a lot of airplanes. I wouldn't let a setback be too discouraging.

Thank you for the suggestion and encouragement.

This mould won't be good for vacuum bagging: I will build it as I would build a stitch&glue kayak, but of 2cm width styrofoam and with glue gun. Its inside will be hollow, and would not stand the pressure. I don't have the equipment for vacuum bagging, also. Last time I tried it with a compressor taken out from a refrigerator, but it could not stand the continous work. Before next try I will build a control unit with a vacuum sensor and a microprocessor so the compressor will be turned on only if pressure starts to build.
For now I think I will wrap It in PE foil.
I know that it is usually recommended with flax to use vacuum bagging because flax floats up, but judging from small objects I have created so far this might not be really crucial. I am using SR8500, which is rather thick, so I am not concerned that it will flow away, flax absorbs epoxy, so it won't become dry, and if I don't wet the flax excessively, there won't be an excess for the flax to swim on.