When you want to do this, your best friend would be a disk sander.
But if you don't have one, you can still get great results with just a mitre box and sandpaper.
In this tutorial I will show you how. It's very easy.
This instructable is taking part to the Hand tools only contest. If you liked it, please vote!
Step 1: Required Tools
You will need a mitre box and saw, and some sandpaper.
Step 2: Cut Your Wood to Desired Length
Step 3: Saw the Corners
Cut the desired corners away.
Optionally, you can make an improvised jig with some Lego and a clamp, in order to help positioning the piece of wood.
Step 4: Cut a Stripe of Sandpaper
Extra tip: how to cut sandpaper:
- Do not use a knife or a cutter, as it will ruin the blade;
- use a needle or an awl to mark the line several times, then detach the stripe.
Free bonus: The needle/awl tip will get sharper!
Step 5: Sand Coarsely
On the outer side of the mitre box, sand the corner coarsely. So far everything is obvious.
Step 6: Now Comes the Trick: Sand Using the Inside of the Mitre Box
The inside of the mitre box will help you keep a right angle between the face and the edge of the wood.
With one hand, hold the mitre box with the sandpaper stripe on the bottom.
With the other hand, slide the wood piece
- keeping contact between its face and the mitre box wall,
- and rubbing its side on the sandpaper.
You can alternate between the previous step for coarse sanding, and this step.
When fully satisfied with the resulting curve, you can use fine grained sandpaper the usual way, to finish off the work.
Step 7: Finishing
Finally and optionally, to give justice to your work, apply linseed oil.
Enjoy the result!