: So, if you were to make your own cabon fibre panels for a s&g build- Could
: you use the method in this link
: http://www.mashie.org/guides/cfbalsa01.html

: Or, would there be issues?

Ewan,

Yes, you could do it that way and yes, there would be issues with doing it that way. But you could work around the issues. As Simeon pointed out, end grain balsa is better suited for use as a core. You could replace the balsa with Core Mat or foam and still do hand lay-up. Or you try the balsa and just live with it if the core fails in shear. Maybe use Core Mat for the bottom panels and balsa for the sides... Lots of options and room to experiment.

One caution - cutting the panels. Carbon wears out saw blades as fast or faster than glass. I'd suggest experimenting with a bonded grit blade and recommend wet cutting and wet sanding whenever possible.

Sam