You will before long experience problems with wood splitting when turning some woods such as Yew or maybe find worm holes etc, Cyanoacrylate is marvellous for filling wood as is epoxy resin. Do avoid breathing in the harmful vapour produced when curing as it is dangerous and can affect amongst other things your nervous system. The Superglue or resin can be mixed with wood dust to match the piece you are filling or as a contrast you can mix in metal filings such as brass or copper. Only mix small amounts at a time as it will set in seconds. Other methods are to flood the crack with the Superglue and then apply the wood dust which will soak in and can be sanded away easily after it has set. I stole my wife’s coffee grinder that did not appear to be wanted due to us buying fresh coffee, pre ground. As it had only been used once or twice I could not remember how it faired with coffee beans but it is excellent at grinding up small wood chips and pieces of bark etc into a fine dust for mixing with epoxy resins or Superglue.

There are various fillings on the market such as brass, copper and aluminum etc, you can experiment and add your own metals or glass or sand or..whatever.

For those not wishing to mix their own, there are several pre mixed fillers on the market such as Inlace, there are a variety of colours and you just follow the instructions. When turning Sycamore or plain woods a band of Inlace obtained by pouring the mixture into a purpose made groove will provide something differant and enhance the turning. It can be cut with your lathe tools without doing any damage and once set sanded and polished as normal.