When working on the wooden model ship kits I found that I needed to plane the edges of planks regularly or taper pieces of dowel to make spars etc. Standard sized tools were very difficult to use on these small pieces of wood. Some years ago I came across a drawing of a very small plane that looked to be made for the job.
After studying the drawings I modified things a little and made my own mini plane. I have found it to be a very useful little tool over the years.
This tool is pretty small but is very easy and accurate to control. You hold the body between your thumb and middle finger and the wooden ball at the end of the handle sits in the palm of your hand.
Below is a photo and a simple drawing of my mini plane.