Heard a bookbinder at the shop talk about PVA glue going bad

Overheard a guy at the bindery supply store on 5th. Said his batch of PVA from last summer started separating after six months. Turned into this watery mess with hard chunks. Stuck a book together and the spine cracked open two days later. Anyone else check their glue dates before a big project?

2 comments

2 Comments

drew_bennett241mo agoTop Commenter

Wait, even if it's all chunky like cottage cheese can stirring really fix that?

stellachen1mo ago

Slight correction there - PVA doesn't really "go bad" in the traditional sense, it just settles out over time. The water and polymer separate if it sits too long, especially if it freezes or gets too hot. I've revived old batches that looked like that by stirring it back together with a little water and letting it sit overnight. Works fine for most projects after that, just gotta test it on scrap paper first to make sure the bond holds.