What's the best glue for repairing your typical plastic kids toys. TYpically I try model glue or Krazy Glue but the repair rarely holds up. Is it just a pipe dream hoping to repair these typical kids toys so they hold up or is there a special glue or method so they form strong bonds that will hold up? Thanks.

 

bvgas,

Generally, the softer the plastic the more difficult it is to glue.

Plastic is a term that is used quite loosely.
There are many different types of plastics and specialzed adhesives that would work with them.
If the material is quite brittle then I would suggest a "crazy glue" type of adhesive.
Any soft, flexible plastic is difficult to glue and plastic welding would be required to repair it.

I'm willing to learn but unless someone else has something, other than welding your toys cannot be easily glued.

Here is a link to a thread in the Welding Forum about welding plastic.

 

If J/B weld don't hold it nothing will.

There are several epoxies that are made for certain plastics I've tried and wor pretty good.

 

As GregH says, there are many types of plastics. Over the years I've worked with lots of different kinds and found ways to repair most. If the toy is polystyrene, like most model kits, try a chemical called MEK, it does 'weld' the poly much better than model glue, but is quite toxic so is not freely available. Some hobby stores sell small bottles of it under brand names, or try your local fibreglass supplier.
Many kinds of softer plastics are repairable with a hot glue gun using the hottest glue and scoring the surface to be glued. For hard, brittle plastics try gel crazy glue, especially Powerbond, available in some woodworking stores and at trade shows. (little known handy fact- all cyanoacrylite glues (crazy glue) will last longer and work MUCH better if you keep them in the fridge) (preferably out of kids reach)

 

Years ago I broke off a piece of my favorite plastic flashlight and was bummed because I thought I would have to trash it because the piece was part of the threaded end that the lens cap and bulb screw onto. One day at wal-mart, I looked at various glues and found one that said it glued any and all types of plastic together.
Thinking it might be worth a try since it wasn't very expensive, I bought it and took it home. It was a two part deal with a tiny bottle of surface prep or some name like that that you brushed onto the pieces and let dry, then used the glue and put the parts together to dry. Well, it worked great and I still have that flashlight and the glue is still holding. I don't remember the brand name but it came in a bubblepack on a cardboard card.