How do I make a slit on a hard plastic lid so it won't crack?

Making banks from plastic square containers from Costco for my grandsons.

  11 answers
  • Jay Campbell Jay Campbell on Jul 15, 2017

    Drill two small holes where the ends of the slit will be, but slightly larger in diameter than the slit. Use the edge of a narrow grinding wheel on a Dremel tool for the slit. Clean up edges with fine 200 grit or greater sand paper.

  • Dysko7710 Dysko7710 on Jul 15, 2017

    Do you have a box cutter? That might work.

  • William William on Jul 15, 2017

    Don't have a Dremel tool?! Draw out you slit. Use a drill and drill a series of holes along the slit. You can sand/file the slit square with a nail file or emery board. Or use a serrated knife and carefully use it as a saw to smooth out the edges.

  • Alradborn Alradborn on Jul 15, 2017

    If you have duct or masking tape using the straight edge of it to "stencil" the slot, you will have a guide line to cut it.

  • Elizabeth Mitchell Elizabeth Mitchell on Jul 15, 2017

    If you have a wood burning set. You hopefully will have a thin knife-like implement that fits into the screw in end of the non heating handle. Heat it and cut a slit. Or if you don't have one of these... you may have a steel knife you won't mind heating...just make sure that whatever you use ...you can hold it without burning your hand. Almost anything that has a slim heatable tip that is sharp and safe to hold while cutting the slit in the plastic lid. There are probably better ideas out in Hometalkers Land, but good luck with your project!

  • Allison Allison on Jul 15, 2017

    If you set them out in the sun for a bit, cutting won't be a problem. I would use a box cutter/razor blade.

    • William William on Jul 15, 2017

      Box cutter or razor blade would be risky. One slip and ....OUCH!!

  • Julie Guerena Porter Julie Guerena Porter on Jul 16, 2017

    Thank you everyone for your ideas. I incorporated everyone's ideas and it worked. Next time will be a smoother job. I look forward to finishing them. Thanks again.

  • Dysko7710 Dysko7710 on Jul 16, 2017

    I use them all the time for crafting, you just have to be careful as with everything else.

  • Elizabeth Mitchell Elizabeth Mitchell on Jul 18, 2017

    You are very welcome...I just hope that you can use some of what I sent out.

  • Debra Debra on Jul 18, 2017

    I use a Stanley tool called, ... Excuse me I cant think if it but it looks like a super long upholstery sewing needle. I use that to puncture's the tough !

    I love that sharp lil fella. Put a few in and straight edge razor the slot out.



  • Debbie Dickinson Cox Debbie Dickinson Cox on Sep 20, 2019

    Thank you all for your suggestions!

    What ended up working well for me was heating an Exacto pen's blade over a turned on toaster several times to heat it up to cut well. More control/safer than a box cutter.