Friday, January 18, 2013
Tejae left a comment on A Tale of Two Nativities: the Original and a Copy (Repaired) wondering if there were safe ways to remove super glue without damage to the glued item.
I had decided not to risk it with the delicate hand painted porcelain figure I repaired for a friend.
Tejae suggested heating might work to loosen the bond. At first, I figured that super glue would start to soften like any acrylic at about 200 F. Too hot. That wouldn't work.
However, perhaps repeated heating and cooling with short blasts from a heat gun would cause the assembly to expand and contract. Eventually this could weaken the bond enough to pull the pieces apart without damage.
After further research, here's what I found.
Super glues are single component glues made from Cyanoacrylate acrylic resin. They quickly polymerize and set when exposed to moisture. [I store opened vials of super glue in the refrigerator to preserve them longer. The cold slows down the effect of moisture.]
Super glues form a powerful bond which resists lateral (bending) pressure, but it has little shear strength - that is, it has poor resistance to twisting or side-to-side forces. So, if the object can withstand it, twisting or sliding the two portions apart (think of opening a pair of shears, i.e., scissors) may work.
There are commercial de-bonding agents for super glues. De-bonding agents are designed to soften cured super glue so it can be easily removed.
De-bonders contain pure acetone or methyl ethyl ketone (MEK). MEK is more aggressive. Both are highly flammable. Avoid breathing the fumes, wear solvent-resistant gloves, and test the surface to be treated first.
This is all theoretical on my part. Have you tried any of these methods for removing super glue or are you game to?