Cyanoacrylate

Cyanoacrylates (CA glues for short) include glues such as Jet, Super Glue and Krazy Glue.

The information provided is general. Always refer to the use, safety and cleanup instructions included with the glue.

Pros

  • Sold in various viscosities with set times from 1 second to 1 minute allowing very quick assembly.
  • Generally non-toxic (but that doesn't mean you should eat it)

Cons

  • CA glues give off fumes while setting that can irritate the eyes (wear goggles and work in a well ventilated area)
  • CA glues give off heat while setting which can lead to minor burns on the skin.
  • Typically has a very quick set time once it is put under pressure and thus is not very forgiving of mistakes during assembly.
  • Does not fill gaps very well although certain of the slower setting CA glues will fill some gaps.
  • Does not work well for end-joint connections.

Cleanup

  • Most CA manufactures sell a De-bonder for cleanup and removal of CA glues.
  • Most De-bonders are acetone which can be purchased in quart containers at hardware stores. Fingernail polish remover will also work.

How to use

  • When cutting the tip off CA glues for the first time it is a good idea to remove the lid to release any pressure that may have built up in the bottle so that you do not risk the glue spraying out when the tip is cut.
  • With CA glues the closer the parts fit together the stronger the bond.
  • CA glues work best in a thin layer between smooth surfaces so any rough spots on the mating surfaces should be smoothed before gluing.
  • Do not touch the tip to the surface being glued.
  • Most places that sell CA glues also sell Teflon tubing and/or extender tips which can aid in controlling the amount of glue that is dispensed.
  • Medium viscosity (5-15 second bond time) and heavy viscosity (20-60 sec bond time) CA glues are used in the same way. Place a small dot (or dots depending on the area being glues) on one surface. Then carefully place the pieces together (you probably will not get a second chance) and hold them under pressure for the manufacturer's recommended time. (see photo below)
  • Practice using small dots of glue to glue pieces together. Experiment using more or fewer dots of glue to determine the optimum amount of glue to use for each type of joint.
  • Very thin viscosity (1-3 second bond time) CA glues are used differently. Place the pieces you wish to glue together and then carefully drop the glue onto the joint. These glues are so "thin" that they wick into the joint creating an almost instantaneous bond. Be very careful because it is very easy to glue your fingers to the materials.

Other Notes

  • While CA glues set very quickly they do not reach full strength for several hours. Refer to instructions included with the glues. Allow for this before subjecting to maximum stress.
  • CA glues should be kept in a cool place out of direct sunlight.
  • CA glues typically have a shelf life of from 12 to 24 months.
  • Unopened bottles of CA glue can be stored in the refrigerator to prolong shelf life but should be warmed to room temperature before using.
  • Always buy a few extra tips when purchasing CA glues. If manufactures instructions for cleaning up after each use aren't followed it is very possible that a glue tip may become unusable until it is soaked in acetone to remove the glue that has setup in the tip.
  • Buy several extra tips. When you finish using a tip, store it into a small medicine bottle (the type with a water tight lid) filled with acetone and let it soak. If you do this make sure you remove the tip from the acetone and let it dry thoroughly before using.

  Interesting Fact

CA glues are sometimes used to suture wounds and to graft skin, bone and cartilage. However, if you happen to graft your skin to the structure you are constructing you should remove it so that you aren't cited for using a material on the structure that is not allowed in the challenge. ☺