csalt, there is a brilliant thing you can get in UK where you put the selves in a bag provded with the product and leave them for about 30 mins then rinse them, can't think what its called but I used it in my London place and it was so good I did the oven in Somerset the week after .... seriously impressed! The Oven in London is old, maybe older than me, and had not been well cleaned before I moved in, for some years (I hesitate to say decades but its probable!) and I had scrubbed and scubbed, but had those bits in the corners etc, the ones that never come off, but these were built up and NASTY. I was impressed when the stuff with the bag really worked :) It was messy, and I had to do it in the bath because the racks were too big for my kitchen sink.
I hate oven cleaning, I try and wipe thing out while still hot, but if its too late and they are welded then I soak the racks ASAP.
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