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Epoxy: Making a Kayak Mold *Pic*
By:Jack Sanderson
Date: 8/19/2003, 8:49 pm

Thought I would share some photos of the carbon fiber mold I am making at work for a K1 racing kayak and some observations that might cross over to hand layups on wood strips.

Below is a picture of the waxed plug covered in a thin gel coat. The gel coat is a very viscous epoxy with a black pigment so that any imperfection in the mold will be easier to see. After the gel coat partially cures we laid 4 layers of carbon alternating the orientation to get the maximum stiffness in the mold. It is then bagged, baked in the autoclave under preasure. This is followed by 4 more layers of carbon which are bagged and baked again. Tomorrow I will lay/bag/bake the final 4 layers.

Observations

1. Even though I felt like we were not wetting out the carbon enough, I was amazed at how much epoxy gets sucked through the bleeder by the vacuum bag and autoclave. I suspect that if we could employ vacuum bagging at home that the weight savings could be significant. It does create a lot of material waste.

2. During the autoclave steps I was reminded of the advice from this board of having your shop hot before layup and let the temp reduce during the cure to prevent bubbles. I guess the vacuum bag and the increased pressure outside the autoclave prevents bubbles during post cure baking.

3. Faring the plug was a lot of work but I got some lessons from a guy who has been doing this for 15 years. This guy could pick up minute high/low spots just with his hand and by rocking a straight edge over the hull. I am still learning but I will try to write some of the techniques down some time.

Well tomorrow I finish the deck mold and start laying up the hull mold. Hopfully we will be building the fist prototypes next week.

Regards,

Jack

Messages In This Thread

Epoxy: Making a Kayak Mold *Pic*
Jack Sanderson -- 8/19/2003, 8:49 pm
Re: Epoxy: Making a Kayak Mold
Chip Sandresky -- 8/19/2003, 11:40 pm
Re: Epoxy: Making a Kayak Mold
Sam McFadden -- 8/19/2003, 10:19 pm
Re: Epoxy: Making a Kayak Mold
Jack Sanderson -- 8/19/2003, 10:25 pm
Re: Epoxy: Making a Kayak Mold *LINK*
JeffHouser -- 8/19/2003, 10:02 pm
So....
srchr/gerald -- 8/19/2003, 9:42 pm
Re: So....
Jack Sanderson -- 8/19/2003, 10:10 pm
Almost finished mold *Pic*
Jack Sanderson -- 8/19/2003, 8:59 pm
Re: Almost finished mold
Ken Sutherland -- 8/19/2003, 9:48 pm
Vacuum Bagged *Pic*
Jack Sanderson -- 8/19/2003, 8:55 pm