Cracked interior plastics?
How to repair your broken trim.

Plane Plastics Plastics Repair Kit How-To video
Plane Plastics Plastics Repair Kit How-To video
Plastic repair guide
For a quick inexpensive fix 
Most general aviation aircraft are getting pretty, well...let's say "experienced."  These planes still have a lot of life left in them but often some of the non-essentials are starting to show just how old they really are.  Interior plastics are a prime example of a good that isn't necessary for flight, and they often get bumped down on your to-do list.  What if there was a way you could fix them?  No, I don't mean duct tape!  I'm talking about a patch job that, if done correctly, can go unseen.

Keep in mind that some plastics are too far gone.  This will show you how to fix minor splits, cracks and warping of your interior plastic.

The basics
 There are several methods to repairing your plastic.  Fiberglass resin, two-part epoxy, and the all encompassing duct tape just to name a few. We've tried them all but the best way we've found is to create a glue by dissolving the same type of plastic material in a chemical solution.

There are generally two types of plastic found in GA aircraft: ABS which is the most common, and Kydex which is primarily found in Beechcraft  and late model Cessna.  The concept of repair is the same, only the composition of the glue is different.

When the glue is dissolved, it's about the consistency of wood glue.  Once exposed to air, the chemical evaporates and leaves behind the new plastic that has now melted with the old plastic.  Most glues only bond to the surface, so the strength of the repair lies only on the top layer whereas this method welds plastic the together.
Here's how

For repairing with the part removed: Start by drilling a small hole at the end of the crack.  This prevents the crack from splitting even further. Next use some tape (aluminum or masking work well) to cover the surface that will be visible, this step makes sure that you get as little glue possible where it can be seen.  Press the tape on well so the glue doesn't seep out onto the surface.  Next, take your syringe of glue and make a thin bead on the backside of the crack.  If possible try to force some into the crack for a better weld.  Let the glue cure, then either paint the part or re-install it as is.

For repairing with the part installed:  Start by stop-drilling the crack. Try to spread the gap slightly while you apply a THIN glue bead to the visible surface.  Quickly wet your finger and wipe away the excess. DO NOT use a paper towel or a rag as parts of it will get stuck in the glue.  This method isn't quite as strong but it works for parts that are hard to get out and aren't under much stress.  Paint to hide your fix.
For repairing parts that are in areas under stress:  Use the first method. But once the first glue has dried, glue some thin plastic of the same composition as the OEM to back of the part to help strengthen the repair.  This works best on flat surfaces.

For straitening warped parts:  Over time due to heat and stress, your plastics may warp.  This can usually be fixed by using splints and light heat.  With the part removed and repaired if it was cracked, use a thin rigid object (like a paint paddle) lightly clamped to either side of the warped area.  Apply light heat with a heat gun.  This is very tricky not to overheat the plastic.  Too much and it will ruin the part.  It can be done and look good, but this step can be difficult.

Plane Plastics offers a plastic repair kit that includes a can of OEM colored plastic chips, stir sticks and a syringe for application and instructions for how to use it.  Kit comes in four colors.  Call for more information. 

Oftentimes repairing is no longer an option,  the parts are just too far gone. When that becomes the case, please look Plane Plastics up.  With over 3,500 parts, and an often under 24 hour turn-around time, we can get you back in the sky in no time!
Next time:   Paints - Why and how to use them on your plastic

The World's leader in Aftermarket General Aviation Plastics.