Another Way to Cut Glass




This will be a short but perhaps useful technique for cutting glass. Forget the glass cutter or the pliers.

You will need
1 A hot wire cutter
2 plate glass
3 a sheet of aluminum foil
4 a pan of very cold water

Start by laying a sheet of aluminum foil on an insulated surface. it should be as wide as the area you want to cut on the glass.

Lay the glass down flat against the aluminum foil
place the hot wire cutter wire on the line you wish to cut on the glass

Turn on the hot wire cutter and let it heat up and heat the glass.

After one minute of heating (time depends on glas thickness) remove the hot wire and dunk the glass quickly but uniformly into the cold water.

When the glass panel is inserted into the cold water the area thats been heated needs to enter the water all at the same time. The change in temperature causes internal forces of contraction to snap the glass instantly. Its wierd but it works.

The glass will break exactly on the line of the hot wire cutter.

Caution always be carefull of sharp edges and the proximity of water to electricity.

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Step 1: The Setup

Arrange your work area in a way to give you unrestricted movement from the heating area to the water trough. You'll have to move quickly and precisely.

Step 2: Heating With the Wire Cutter

If you are cutting regular glass, a sheet of aluminum foil will insure more even heating from the hot wire to the glass. its not neccessary with a mirror. the reflective layer on the mirror acts in the same way as the aluminum foil. With a mirror it may be neccessary to score the plastic coating on the other side if the glass to insure a clean separation

Step 3: Snap!

Thats what you should hear as you quickly insert the glass evenly across the heated area into the cold water. Use very cold, almost freeezing water. I apolgize for the picture, but thats what it should look like.
The heated line of the glass should enter the water all at the same time.

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    7 Discussions


    Reply 9 years ago on Introduction

     Don't be a troll. That's like saying mixing pool chlorine and bleach is a good idea.  


    Reply 9 years ago on Introduction

    Uh, what? Pool chlorine and bleach are both sodium hypochlorite I think, so I don't know what that would do.

    The thing that I said works. If you dip the string in gas, wrap it around a jar or whatever you are cutting, light it, wait for it to burn out, and drop it into cool wayer it will crack along the line where the string was.


    Reply 9 years ago on Introduction

     Have you tried this technique, it sounds like it would set the whole durn house on fire, and burn someone severally.  


    Reply 9 years ago on Introduction

    I have done it several times. I don't do it in the house, but the flames are not as large as it sounds like you think they would be. They are only a few inches tall.


    10 years ago on Introduction

    Awesome! I had to cut 85 glass mirrors for my solar cooker, and used some spare HW (widia) little cutting wheels. Still, the last mirrors went wrong.

    1 reply