Advice wanted from the handy person types:

I’m pretty good at things like doing electrical boxes, hanging drywall etc. The drain pipe and trap on our kitchen sink is shot. It’s been patched so many times. It’s basically made of glue and JB Weild. I don’t want to hire a plumber because I think I can do it myself. However the threads on the sink that connect to the drain are gummed up. Wall connection is probably fine. Sink is 70 years old and horrible.

Am I nuts? 

 @134318c2 Even *considering* this makes you braver than I am. Ergo, I have no advice worth giving (other than, I guess, keep a first aid kit handy in case something goes screwy, and a fire extinguisher in case it goes *really* screwy) but I wish you the best of luck. 

 @134318c2 

Where on this diagram are the threads ruined & what material are they?

And no, you are not nuts; plumbers are expensive and this work is usually less complex than drywall or electrical.

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