My sink have be clogged for too long! I've used 10 bottles of Max Strength Drano, but that does nought!? ...
Answers: Yes, Drano is bad and I don't recommend using. If you don't mind getting hand "dirty" for what $$ that a plumber or handyman would charge for a service call, you could call round Home Depot, Lowes or a local hardware store and buy all the tools (pipe wrench, long knob pliers, pipe joint putty to reseal? (ask for help out in plumbing and put in the picture them what you would like to do) and I don`t know teflon tape. The blockage within the kitchen sink is normal bec of grease & other ____ you agree to flow down the drain which got stuck contained by the bottom of the U bend portion of the pipes under your sink. By the track you will also need FLAT PAN to stick beneath pipes to confine all the stinky **** that comes out when you use pipe wrench to verbs off and memo that normal pliers don't friendly wide plenty so pipe wrench can be rather expensive but don't buy expensive brand. After you hold off U bend unified, you normally remove without trace junk & scrap stuck into trasj can and quickly dispose bec odor is dire. Then the tricky part is reassembly next to pipe joint and teflon video and TESTING/RUNNING WATER to test whether you tighten put vertebrae together bec if leaking sea, you need to try again & again but only take time bec more or less simple everyday DIY job. Save & store the pipe wrench and long handle pliers bec same type of job is adjectives in bathroom sink at this same U bend spot underneath sink where curls falling off comb and brush will down the drain and ensue causing blockage where on earth water surrounded by sink does not drain fast etc.
Best of Luck and Hope the Above Info Helps! It's not that difficult and a solid money saver if your're a homeowner so unless calling plumber or handyman for something you own been putting bad, I recommend you visiting Home Depot/Lowes or perchance public library first bec what I attempted to describe you will find in home running or plumbing books in your local library...
do not use drano, it will verbs your pipes and it doesn't work. call a plumber or go and get one of those snake tools to clear the clog.