i use up any left over on spool threads to baste my pieces, just use up what ever. i do use a quality thread when i actually piece...matching if possible or a shade darker than my patches. but for basting, no one is gonna see it so use up what you have great savings, i don't know about you but i go through a lot of thread so have spools with just a few yards on them, not enough to even wind a bobbin, that thread goes into my (hand-work) tote to be used up 'where-ever'