In uk.rec.motorcycles Spike <
aero....@mail.com> wrote:
> For a crack stopper, I?d suggest a 2mm drill, and a problem you might have
> is that the through-thickness crack front might not be square across the
> thickness. You?ll need to examine each crack to ascertain where the ends of
> each crack is both inside and outside, and then drill along the crack
> front, which might not be square to the local surfaces. This is to avoid
> drilling larger holes than needed.
>
There's enough material for 5-10 mm holes, but I'll look more carefully
to see if the crack inclination can be discerned.
> Another thing you might consider is to epoxy short pieces of steel across
> the ends of each crack, before applying the glass-fibre matting, whether or
> not you drill crack-stopper holes. If doing this, clean the steel strip
> with alcohol before applying the epoxy and avoid handling the bonding
> surface. Apply pressure until the epoxy sets.
I wonder if using a small screw, washers and nut clamping the ends of
the cracks flat might have a similar effect. That's easier to do,
looks aren't a huge issue. Flatness near the crack ends might be
as the cracks follow the curve from the bottom of the case to the
corners. The end area might not be entirely flat.