How to Fix Cracks in Plexiglas

Plexiglas is an extremely strong plastic product that is made of the same base material as acrylic paint.

Plexiglas withstands a lot of wear and tear, but can crack from the edges.Plexiglas withstands a lot of wear and tear, but can crack from the edges.
It replaces glass on many products, including cars, boats and airplanes, and resists breaking and damage better than glass products. However, over time and under pressure even Plexiglas will crack. Stopping the crack where it is and filling it in is a temporary fix until you can get the Plexiglas professionally repaired or replaced.

Attach the smallest drill bit you can find (preferably 1/16-inch or 1/8-inch) to an electric drill. Line up the bit with the very end of the crack and slowly drill a small hole through the Plexiglas. This interruption immediately stops the crack from getting any larger.

Use a can of condensed air or a damp rag to remove any dust from the drilling. For small cracks that are barely noticeable, this may be the only fix necessary, since the crack will not get any larger.

Inject methylene chloride adhesive into the crack to repair larger cracks. You can find this adhesive at plastic and boating supply stores, as well as some auto supply stores. The kit should come with a small injector; follow specific product instructions in case your chosen product requires any mixing.

Wipe off any excess adhesive from around the crack with a tissue or damp rag. Allow the adhesive to dry completely (per product instructions) before applying any pressure or vibration to the Plexiglas surface.

Things You Will Need

  • Electric drill and drill bit
  • Condensed air or rag
  • Methylene chloride adhesive
  • Injector
  • Tissue

Tips

  • Filling in your Plexiglas crack is only a temporary solution. On any surface that undergoes any vibrations, such as car windows or boats, the crack will open again with a little wear and tear. Get your Plexiglas attended to professionally as quickly as possible.
  • For opaque Plexiglas pieces, glue a strip of thin Plexiglas to the back of the area to reinforce the crack sealer, giving it a little more longevity.

About the Author

Samantha Volz has been involved in journalistic and informative writing for over eight years. She holds a bachelor's degree in English literature from Lycoming College, Williamsport, Pennsylvania, with a minor in European history. In college she was editor-in-chief of the student newspaper and completed a professional internship with the "Williamsport Sun-Gazette," serving as a full-time reporter. She resides in Horsham, Pennsylvania.