Occasionally while sanding a bowl I find a hairline crack. Filling it with CA glue leaves a blotch around the crack where the glue soaked into the surface. I have learned to avoid this by the following method.
Using an old candle I rub around the crack parallel to the crack. Then I take a dental hook tool and clean any wax out of the crack, then fill the crack with CA and spray on the hardener. The wax sands off, leaving the filled crack.
I've done the same thing except i wipe a thin coat of whatever I'm going to finish the bowl with over the crack. It prevents the blotch, and doesn't have to be sanded away.
Old guy
How do you get the surface of the repair smooth and level?
I try to build up the fill in the crack slightly proud of the wood, then just put the piece back on the lathe and sand it as I normally would. Most of the thin finish coat is sanded off, as well as the rough parts of the CA, so the final finish goes on smoothly and evenly.
Old Guy
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