All this talk about retreading the dreaded serger makes me want to try again......first time, after hours of trying, mumbling, I ended up taking the darned thing to JAF and had person there do it..took a blink of an eye...anyway...this time, one needle as removed and all 4 spools of thread....two yrs ago, dd was in a wedding party and her gown needed hemming with a rolled hem......called my then dealer of bl and asked if she would help, although I had a Viking...sure she said...she could not get it to work after changing threads and removing needle...did it on her bl serger..Viking has sat on the self untouched since then.....dare I find the manual and try????again!!!! No it's not air threaded..color coded paths, but to me, still very complicated..I don't know what I was thinking when I bought the dumb thing!