If your Canon PIXMA MP810 gets a paper jam, then you will have to disassemble the printer, in part, to fix the problem. Though you cannot completely disassemble the printer, there are a lot of components you can remove. With the Canon MP810 you can easily take the printer apart to a certain extent to fix your problems. Be warned that total disassembly will void your warranty and should only be carried out by Canon.
Switch your PIXMA printer off.
Pull down the front panel of your printer. Lift the LCD screen and scanner up.
Remove paper from the front paper tray. Remove the paper from the rear paper tray.
Remove the rear panel, by pushing the lever up and pulling the back panel off. This will give you access to the back of the printer.
Remove the paper cassette. With the cassette out, you will have completely disassembled the device as much as possible, and you will have access to your printer.
Take any paper and slowly but firmly pull it out.