: Fellas,
: My North Star pride and joy is going the way of my Guillemot in that I'm
: using it so much I'm quickly scratching the hell out of the bottom of the
: hull - it's all stoney landings around here. Rob in his instructions
: mentions a witches brew - mixing graphite i think in with the epoxy to
: provide a slippery area that resists scratches.

I've used this and it works. It gets scratched too but the slipperyness and hardness combine to damage less.

Graphite Coating for Protection
If you are really rough on you boats you may consider a graphite coating for the hull bottom.
Graphite powder and Colloidal silica mixed with resin makes a very hard, slippery surface that can protect the bottom of your boat from injury. Graphite powder mixed with epoxy resin produces a black opaque coating that does not need varnish. This is the same graphite powder you may be familiar with as a lock lubricant. This surface is also low friction. Objects hitting the surface tend to slide off causing less damage.
This coating is applied below the waterline on the boat bottom and can be re-coated as needed. Mask off the area and apply several thin coats.
Per batch of resin add 25% graphite and 5% silica. Graphite powder (#423) and Colloidal silica (#406) is available from
West Systems.

All the best,
Rob