Mold Glass Size

So you have all these molds and glass, but how do you measure the necessary mold glass size?

Molds come in different shapes and sizes, and to determine what size glass you need for this mold might present a problem.

Never cut your glass more than ¼ inch larger than your mold.

If the glass is more than ¼ inch larger than your mold, the glass might slump around the outside of the mold.

Slumping on the outside of the mold can cause it to fall unevenly, or form around your mold trapping it in the glass.

If your mold is round with a tiny or no rim, your glass is going to slump into the mold.

The more depth to the mold the more the glass will sink and decreases the size of a rim.

There are a couple of ways you can determine the size and shape of glass you will need for your project.

I am sure there are more ways, but I will discuss a couple of them here.

Place your mold on your glass and draw around it with a permanent marker.

Once done, you can cut this design out using a glass saw, or if it is not too detailed, use a glass cutter.

If your mold is circular, measure the dimensions of the mold, and using a circle cutter, cut the glass.

Make sure that you have cut this glass no more than ¼ inch larger than your mold.

Trace your mold shape onto paper.

This paper drawing of your mold can then be glued onto your glass with rubber cement.

Be sure to also put the rubber cement on the outside of your paper shape.

Once dried, this shape can then be cut out using a glass saw.

The rubber cement will keep your pattern from dissolving in the water from the saw.

Line the mold with aluminum foil.

Press the foil firmly inside the mold.

Trim the edge of the foil.

Remove foil and flatten the piece.

Use the shape as a pattern to cut out the glass.

Remember to cut the glass the same size as the mold opening or just a little bigger (no more than ¼ inch).

The main concern when slumping with different shapes is not to trap the mold with the glass.

Watch the piece carefully and make sure it slumps to your desired look.

Keep the slumping temperature low and go slow.

The idea is to ease the glass into the mold.

Play around until the right temperature for the particular glass and project is reached.

The piece could be slumped at a lower temperature than expected.

Take accurate notes to discover what you did and what happened during your slumping procedure.

Return from Mold Glass Size to one of the following pages:


Mold Glass Size to Glass Fusing Made Easy

E-mail Address
First Name (optional)

I keep this private.

Learn Glass Fusing

Learn More

Site Affiliate Links

Delphi Glass