I dyed my Ikea dining room chairs RIT fuchsia about eight years ago, but sunshine + time had faded the chairs to a pale pink. I followed the instructions for the front loading washer, used a ratio of one bottle to two chaircovers, dying two covers per load, and used a watering can with a long spout to pour the hot dye mixture into the detergent receptacle. Also, instead of mixing the salt with the hot water and pouring that in, I just dumped a cup of salt into the detergent receptacle and poured the hot water on top of it, that worked well in terms of not splashing salt water all down the front of the machine and in terms of not having a ton of salt left at the bottom of the water mixture. As promised in the RIT dye instructions, the dye itself did not damage my washing machine, however, the 1 cup of salt per load seems to be taking a toll, corroding some parts of the machine, especially around the detergent drawer or any part of the machine that is metal, has stickers, or painted text/symbols.
Would I do it again? Yes - eight years ago I dyed the covers by hand in bins and it was 10 times the work as doing it in my washing machine. Maybe next time I will put the cup of salt directly into the barrel and not pour it through the washing machine parts at all"¦
In my washing machine, the extra hot load is a two hour cycle, then you have to wash the items after the dye cycle. Allocate A full three hours for each dye batch.

Had some velvet child chairs that had faded but came out beautiful with the Rit dye