| A serger needs thread - 2 or more spools depending on the technique. Since I like to have my serger thread colors somewhat match the fabric I'm serging I came up with this technique so I don't have to buy 3 to 4 spools for every color fabric I will serge, especially for colors I know I will only use occasionally (eg apple green)
The technique uses: empty regular thread spools (eg Gutterman); 1 spool of serger thread (eg Maxilock); blue poster putty (eg Blu Tak), a sewing machine bobbin and sewing machine with its bobbin winding mechanism and, well, my hands. ( It works because my machine has an upright bobbin winder - it may not work on all sewing machines if you can't easily access the bobbin winder with room enough for an attached empty spool.)
I take a ball of poster putty and smoosh it into the end of an empty thread spool. Place the empty bobbin on my sewing machine bobbin winder, positioned as if I'm going to wind a bobbin. I push the empty spool, with putty end against the bobbin, pushing it firmly trying to make sure it is centered and secured. (If it isn't centered it wobbles.) I hold a cone of serger thread in my left hand, wind a bit of the serger thread onto the empty spool, press the sewing machine pedal and begin winding - using my right hand to gently guide the thread so it winds evenly onto the spool. Once the winding is done I remove filled spool, pull out the poster putty (to be used again) and I have an extra wound spool in the color I want to use in my serging.
To see them steps involved, here's a set of photos in above URL: (or this:
(I tried other methods before the poster putty: I first glued a bobbin onto the empty spool, but then I had to keep buying new bobbins. Then I tried press apply velcro - one side on the bobbin and the rest on empty spools. But that got tiresome cutting velcro and affixing. When I read Sew4Fun's blog about attaching binders to sergers with poster putty - well I found this stuff could be used for winding.)
Finally - you may wonder how much such a wound spool holds versus a bobbin, well I estimate that it is two and half times greater than a bobbin - based on the very useful tip written by SewVeryTall about exactly how much bobbins hold: