Maintenance tips that apply to several Royal models
Royals from the '40s and perhaps a few decades before and after, often have backspace trouble. If you press the key, and the carriage moves but does not actually go back a space, try this fix. Tip the typewriter up on it's back. There is a silver metal lever that moves left to right when you press the backspace key. Using a screwdriver, place the tip under the lever as shown in this photo -- just to the left of the spring and black piece of metal.
Now lift upward, toward the front of the machine, with a bit of force. The goal is to bend it just slightly. Try the backspace key now. Does it work? If the backspace key sticks in the downward position, you may have bent the lever too far. Not to worry, just bend it back slightly by pressing on top of the lever with your screwdriver.
With some trial and error, this will hopefully get your backspace working again.