Sometimes ago, I bought a "Scratch Map" which allows to scratch the places I've been on a map and expose it on a wall. This map is great, but it doesn't have standard dimensions, and finding a picture frame that has the right dimensions and that I like wasn't possible. In the end I decided to do it myself and here's the result :

Step 1: Material

For this easy DIY picture frame you will need :

A wood plank
5mm plywood
Wood glue
Sandpaper
Paint & Stain
Varnish
Picture frame wall hanger
Small screws and washers

Step 2: Cutting the Wood

I begin with cutting a plank into two piece, one of length of a side and an other of the length of the top of the picture frame. Then I cut them along the grain to obtain the four sides of the frame.
After that I used my table saw to make 5mm grooves on one side of each plank to create a space where the back panel will fit and maintain the map against the frame. I finish the frame by cutting every extremity at 45° making sure the inside dimensions of the grooves matches the dimensions of the map (plus 1 or 2mm). The last cut was the back panel made of plywood, its dimensions are the same as the inside dimensions of the grooves to fit perfectly.

Step 3: Assembly

Now is the most delicate step : glue four 45° angles together in order to get a rectangle. For that, the easiest technique is to use a ratchet clamp to tighten the angles with one another, just make sure the inside angles are 90° and let it dry.
Once it is assembled, we can try to fit the back panel in the groove, if it doesn't it is still possible to adjust its size.

Step 4: Finishing

At this point, you can consider the picture frame done, apply some varnish on and go to the next step, but I wanted to customized it a bit.
To do that, I used my Dremel with a wood engraving bit to write some text on the top and the bottom of the frame, then I fill the groove I just made with black paint to highlight the text. Once it is dry, I sand the whole frame with 80 and 120 grit sandpaper to erase any paint smudge and I apply one coat of stain to give an old look to the frame. Finally, I apply several coats of spray varnish so my frame will last longer in time

Step 5: Hardware

The picture frame is now ready to be hanged, you just have to slip the map between the frame and the back panel and secure it with the screws and washers. To fix it on the wall, I screw a hanger especially made for pictures, even if it is not perfectly centred, it has small teeth to make the adjustment.
The picture frame is now done, le funniest part is to come : discover new countries and scratch the regions on the map.

If you liked my Instructable, don't hesitate to check my Youtube channel :

https://www.youtube.com/channel/UCBTC9EX_tzzbslbxbwbjp8A