Trenails are added using toothpicks. I used tape to define the location for the trenails. Holes were drilled along the line.
![Trenail holes drilled](http://blog.clockwork-orrery.com/wp-content/uploads/sites/4/2019/04/sultana_build_log_033_01-512x341.jpg)
The toothpicks are glued in.
![Toothpicks inserted into trenail holes](http://blog.clockwork-orrery.com/wp-content/uploads/sites/4/2019/04/sultana_build_log_033_02-512x341.jpg)
After drying, the toothpicks are chopped off and the surface is sanded down.
![Trenails sanded down](http://blog.clockwork-orrery.com/wp-content/uploads/sites/4/2019/04/sultana_build_log_033_03-512x341.jpg)
Getting a straight line is a challenge.