I have a double kitchen sink, which is completely clogged. I've tried plunging it, both with a regular plunger and with 1 second plumber, neither of which made the slightest difference. I tried disassembling the pipes, but I have a non removable trap, so I can't get very far. Do I have to call a plumber?

You have clog in the horizantal drain pipe, remove the "J" bend from the trap and snake the drain line, (see image). You will run into a 90 degree bend about 8 inches in but once around that you only have to put out 6 more feet of cable. After, flush with hot water, if you are not able to remove the J bend then you would need to call a plumber,Good Luck.

John