How to Make a Resin Mold Using a Plastic Cutting Board

A Step-by-Step Guide to Crafting a Custom Resin Mold

If you make a lot of projects using resin, you know that molds and supplies can be very expensive. Sometimes, in the case of molds, there are limited sizes and you may not be able to find what you need. I came up with an easy solution and will show you how to make a resin mold using a plastic cutting board.

Plastic cutting boards are cheap and are the perfect material to make molds but there are a few things to know beforehand. Gather your supplies and follow along as we make a custom mold!

Materials:

• Plastic cutting boards measuring approx. 15 x 20 (<– affiliate link!)
• Non-stick tape such as Tyvek
• A miter saw, table saw and/or circular saw
• A special saw blade designed to cut non-ferrous metals and plastics (<– affiliate link!)

Notes About the Project:

Do yourself a favor and buy the special saw blade… A regular saw blade can be used but it will melt the plastic and not produce a clean cut. It can also overheat your blade because it is working too hard. The blade I have listed is an inexpensive blade with very good reviews and should be fine for infrequent use. I purchased and use the blade shown below from Harbor Freight.

Step One

Cut the first cutting board to the desired size of your mold. I wanted a square mold measuring 12-1/2″ x 12-1/2″ because that is the maximum width of my planer.

Save the scraps to use as spacers for other molds, if needed.

 

Step Two

Determine the depth of the mold. 2-1/2″ deep is the perfect depth for mine so I cut the second board into strips, then cut two pieces from the strips at 12-1/2″ long.

Step Three

I started using screws to secure the sides to the base but it didn’t work for two reasons: the cutting boards I used were only 3/8″ thick, and my screws are #8 so they were a little too thick. So I secured the shorter pieces using the Tyvek tape on the outside of the side pieces folding over the bottom of the base.

Step Four

I measured the two remaining sides of the base, including the strips secured to the perpendicular ends, and cut two strips. I secured these on the outside with Tyvek tape, as well,

Before using the mold:

Now, apply the Tyvek tape along the seams on the inside of the mold. This will keep the resin from leaking all over the place and making a mess!

Make sure to use a silicone spray (<– affiliate link!) inside the mold before pouring resin. Though I’m sure the resin won’t stick to the plastic cutting board pieces, it doesn’t hurt to make sure the piece will unmold easily.

Unmold the Resin Piece:

Remove the tape from the side pieces to remove the piece from the mold then pry the piece off the base, if necessary.

Reapply the tape so that the mold is ready for the next use!

Have questions about how to make a custom resin mold using plastic cutting boards? Leave a comment below!