This is an entirely hypothetical question as it does not apply to any current project.
When repairing dowel joints, should one re-use old dowels if they look good, or replace?
On the one hand, dowel failure occurs due to them going out of round over time, but on the other, the dowels in the furniture are perfectly acclimated.
1. Clean and re-use the old dowels.
2. Remove and replace with dowels of the same size.
3. Remove, drill for the next size up and insert a new dowel.
4. Use a Domino if you have one.
5. Burn it – anything made with dowel joinery is the work of Satan.