Wet lay-up improvement advice

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#1

Hello everyone,

I am currently working on jute fabric/epoxy composites using vacuum infusion. However, a new alteration to my fabric plies requires the wetting of the plies prior to the lay-up. So I decided to employ wet lay-up vacuum bagging with the following set-up:

glass mold -> mold release -> peel ply -> wet laminate stack -> peel ply -> vacuum mesh -> bagging material -> vacuum port

My first atttempt yielded a casting with a poor wetting on the mold side as seen in the images at this link: http://i192.photobucket.com/albums/z67/MikePinto_photo/Natural%20Fiber%20Composites/100_0166_zpsfd23c8f6.jpg

The stack was consolidated at -20in Hg

Any suggestions on what went wrong and how I can improve this?

Thanks for any help

#2

Apply a generous amount of resin on the peelply, or even under the peelply.

Still you can expect some problems, as the jute fiber holds a lot of air, even while being laminated. Putting things under vacuum after impregnation expands the air still trapped inside the bundle, causing larger airpockets than expected.

Wetbagging is not asubstitute for sloppy laminating, and sloppy laminating cannot be avoided using these very hard to impregnate fibers (at least not the natural fibers I have been working with).

What is the reason that resin infusion is not possible? Or is that classified info?

#3

Resin Infusion is not possible since I am applying through thickness reinforcement to each layer, which requires they be wet with resin so the reinforcement will stick.

I will try again with just more resin and see what happens.

Do you think less vacuum would help?

Thanks again