Brake squeal observation

I have aT Bird if you don't get the belt adjustment just right it actually sounds like baby birds chirping. The first time the dealer changed the tire I left and had to pull over searching for rodents. Mgr looked at me like I was crazy. After he heard it for himself he said he never heard such a noise.
 
My original pads squealed but were worn so I replaced them with EBC. The squeal returned with the pad about 60-70 percent. I cleaned them w/brake cleaner and bedded them in, not exactly as EBC recommends. That cured it for about 2-3 thousand miles before it returned. Next I replaced the rotors and used oem pads. The squeal stayed away so long I just knew it was a fix. Then the squeal returned. I did exactly what you said not to do scrub pad and degreaser on the rotors, sand paper on flat surface then rub the pads back n forth, dry with compressed air, followed EBC bedding process. There was a dark coating on the rotors and pads surface so you are right about contaminates. I often ride in the rain and in heavy traffic (lots of swerving & braking) If it returns I'll try bedding then again. I could ignore a squeak. But it sounds like a school bus or train stopping. Someone mentioned cutting a groove in the pad. We used to chamfer the edges of pads after eliminating other causes. Seemed to work at the time.
 
I have always scuffed the pads and rotors with 1000 grit paper . It removes the glaze but would take a lot of rubbing to alter the face of the pads . Older rotors can wear some strange profiles into pads so they are rarely perfectly flat . EBC would never condone this coz it creates very harmful dust
So mask up ! 30 years ago , this exact procedure was printed in the Haynes manual for my mk 1 ford Escort , to stop brake squeal but it didn't advise masking up and mentioned very little bout the asbestos they contained back then !
Brake cleaner is the answer to most ills , that stuff jus kills grease and crud and wasps dead , smells nice and keeps the dust down !
 


Those rotors are so hard i use 120 grit on an air grinder flap wheel - doesn't do anything harsher than ruff em up a bit. 1000 grits WAAAAAY too fine (on the rotors) 400 for the pads
 
D@mn, I was tryin to bait Art into a Lemon Pledge endorsement



Patience Grasshopper. I was asleep earlier but having taken the "Pledge"* feel compelled to say it looks like a can of Lemon Pledge 'Stealth' with a stuck on label. If it works it proves it must be.

*We are a secret society headed by Art (like followers of the 'Phantom'), committed to eradicating dirt and grime wherever we find it. We are close by and ever vigilant, some think we are a merely a myth until they come across a gleaming object radiating a force-field repelling all contaminants known and unknown to mankind with just a faint whiff of lemon fragrance or the new 'Stealth' pleasant scent in the air. Believe and take the 'Pledge' now!