Cutting glass – instructions in 4 steps

Ad Blocker Detected

Our website is made possible by displaying online advertisements to our visitors. Please consider supporting us by disabling your ad blocker.

  • If you only want to cut glass rarely and simply, you can get by with simple tools. A little practice on leftover pieces or broken glass won’t hurt.
  • If cutting glass is part of your hobby, such as Tiffany glazing or recycled products from glass bottles, etc. then special tools such as a wet grinder are useful additions.
  • Since uncut glass can cause serious injuries, gloves and safety glasses are strongly recommended. The finest splinters should best be bound with cutting oil or water and covered with kitchen paper or similar. be removed.

glass cutting material

The right tool

The glass cutter must be able to cut the thickness of the glass pane. The number on the wheel on the glass cutter tells you how many millimeters your glass cutter is suitable for. Of course, it also depends on the right tool quality (diamond or steel, etc.). You can find out more about both in our glass cutter test.

Whether you just want to replace a pane in a lantern or do some crafting with glass: Sooner or later, the task of cutting glass comes to almost everyone.

Do-it-yourselfers and creative hobbyists in particular often benefit from including glass as a material in their range. Since the properties of glass include “hard” and “very brittle”, glass processing is a problem special requirements.

As is often the case, the right tool and the correct use of it are the key to success.

material Tool
  • Glass
  • Cutting oil or petroleum
  • Glass cutter
  • Glazier’s square, alternatively thicker (wooden) ruler
  • Crumb tongs
  • Diamond file, whetstone, diamond sandpaper or multitool with diamond grinding attachment
  • possibly a glazier’s or tile hammer

1. The choice and setting of the glass cutter


In order to set the glass cutter correctly, the glass thickness must first be measured.

The glass cutter must appropriate to the task to get voted.

First of all: A glass cutter that has been lying around in a toolbox for years will certainly not help you get a clean cut, at least with the open wheel.

It is definitely easier for a beginner to use a regular glass cutter with steel wheels. For this reason, this guide refers to Steel glass cutter.

Diamond glass cutters belong in the hands of more experienced glass workers.

If you are still thinking about getting started with a diamond glass cutter, you should take a look at the following list, which shows the advantages and disadvantages of a diamond glass cutter compared to a conventional steel glass cutter:


  • much less pressure is required when cutting
  • Direct cutting along templates is also possible
  • no cutting oil necessary


  • Using the tool correctly requires some practice
  • Diamond cutters are more expensive
  • Diamond can easily become unusable if handled incorrectly

Your glass cutter must be suitable for the thickness of glass you want to cut. The numbers on the adjustment wheel show the different glass thicknesses that you can cut with your tool.

Determine the glass thickness and then turn the wheel to the interface that has the appropriate number.

There are single vision and multi-vision glass cutters – make sure your glass cutter is suitable for your glass thickness.

Tip: If you want to cut glass more often, you should store your glass cutter upright in a screw-top jar with a piece of sponge soaked in plenty of cutting oil or petroleum at the bottom. That’s how glass cutters remain sharp and functional for longer.

  • View glass cutters on Amazon »

2. First: cut or score the glass plate

glass-cutting-glass-cutter through

Pull the glass cutter with cutting oil through it in one go with about 3 kg of pressure.

In preparation for a clean cut, the glass pane should be thoroughly cleaned and placed on an absolutely flat surface. The glass should be at room temperature.

Then you should put on work gloves and safety glasses.

If you have a glazier’s square, you don’t need to mark the cut beforehand, you can Simply measure the desired size. Attention: Add the 2.5 mm between the system and the cutting wheel of the glass cutter!

If you want to use a thicker ruler, a bar or something similar, you should mark the desired cutting line beforehand mark with a marker.

Before you cut or score the glass plate, put a drop of cutting oil on the glass cutter if it has not already been stored standing up in a cutting oil or petroleum sponge.

We use the glass cutter with the smooth side (opposite the adjustment wheel) – just once! – pulled along the guide. What is important is:

  • steady pace
  • constant pressure (approx. 3 kg – try it with a pen on a flat kitchen scale)
  • consistent hand position

If done correctly, the scoring will be accompanied by an even tone.

Tip: For example, you can use the glass from a discarded old window to practice.

3. Afterwards: break the glass


Immediately after scoring, break the glass in your hand or over an edge.

Don’t let a lot of time pass between scoring and breaking. Experts say that the “fissure cools down”which leads to a more unsightly break.

In fact, scratching creates tension in the area of ​​the fissure (scoring line), which relaxes again over time.

The pressure when breaking should be on the scribed line from both sides (to the right and left of it) must be the same. The hands should be the same distance from this line and apply equal pressure from both sides when breaking.

You can also break the glass over an edge – the following also applies: the holding hand should be the same distance from the fissure (the scratched line) as the other hand applying pressure.

4. Sand down the cut edges

glass cutting files

The razor-sharp glass edges can be filed blunt with a diamond file.

Be sure to do this before sanding put on a respirator mask!

The very sharp edges can be sanded with a diamond file, a grinding stone, diamond sandpaper or with a multitool with a diamond grinding attachment.

If you use a power tool, remember not to let the glass get too hot.

That could to tensions in the glass and lead to shards.

5. Interesting facts and other tips

5.1. Cut bottles

You can find out how to cut a glass tube or bottles and sand the cut edges in our article on making candle holders and lanterns out of glass.

Instead of disposing of them in the glass container, you may want to cut and cut your wine bottles in the future Process into vases, lanterns, etc.

5.2. Cutting safety glass

Safety glass is available under the names IT G and VSG. If you try to cut toughened glass, the entire pane will crumble into glass crumbs. Neither can fireproof glass cut – i.e. Pyrex or fireplace discs.

At best, LSG glass can still be cut. But this is also difficult because it has to be scored from both sides and the film has to be cut separately after it has been broken. There is one high chance that the glass will be damaged.

Instead of cutting (VSG or ESG) safety glass, it is better to buy such a glass pane as a finished cut or have the glass cut.

Wired glass Cutting it, on the other hand, is just as difficult or easy as cutting normal glass, except that the internal wire mesh still has to be cut through. Depending on the thickness of the wire, it can be bent back and forth or with help a small side cutter, angle grinder or similar. be severed.

Tip: To cut through the film of laminated safety glass (VSG), you can fill the already broken Ritz with spirits and light it.

glass-cutting-circle or hole

A circle or hole glass cutter is worthwhile if cutting glass is part of your hobby.

5.3. Cut hole in glass

Whether you want to cut a hole in a glass or cut a round glass out of a normal glass plate: there are special ones for these cases Round glass cutter.

In the part that is to be broken or broken off, segments are scratched with a normal glass cutter, which are then Broken piece by piece become. Alternatively, you can also do this Crumb tongs use to cancel.

5.4. Cutting glass with Flex

It will probably be very difficult, but it may occasionally be possible to cut glass with a flex. The angle grinder should do this with a diamond cutting disc be equipped and cooled with water or work very slowly with many breaks. The same applies to cutting glass with a Dremel.

If it is important, consider having the glass plate/glass cut or ordering the glass custom-made rather than cutting the glass yourself.

  • View respirator mask on Amazon »

5.5. Sawing glass

In the professional sector there are machines for sawing glass.

As a DIY enthusiast, you can attempt to saw glass by using a jigsaw Diamond saw blade (round) is clamped. The following also applies here: slowly and without much pressure work so that the glass does not heat up too much.

5.6. Cut glass without a glass cutter

Success is uncertain, but occasionally the attempt is successful: a wick (thick cotton thread like potholder thread) soak with alcoholplace on the desired score line and light.

Then immediately dip ice (water) onto the break or the pane in ice water. With a bit of luck, the glass will break on the desired line.

5.7. Cutting mirror glass

Mirror glass is cut in exactly the same way as a normal glass plate.

However, mirror glass is generally more expensive and the cut edge may be used when cutting and grinding the coated back cannot be damaged.

5.8. Cutting thick glass

Thick glass is cut in the same way as thin glass, although it can work better if you tap along the fissure from below – i.e. from the underside of the glass plate with one Glazier’s or tile hammer. You have to work quickly and then break it straight away as described above.

5.9. Electric glass cutters

Basically, such machines and devices only exist for the professional sector.

At best, under such a term Multitools with attachments or tile cutters Also offered as glass cutters that are electrically operated. These are not recommended for glass cutting by hobbyists and DIY enthusiasts.

6. The following 7 things should definitely be avoided when cutting glass

You should definitely avoid the following when cutting glass:

  • score or re-score several times
  • start again (always score in one, even stroke)
  • Apply too little or too much pressure when cutting or breaking (the common motto is: with feeling, but courageously)
  • cutting tempered glass or VSG glass
  • use uneven surfaces
  • allowing too much time to pass between cracking and breaking
  • Ignore the risk of injury

Image credits: all VGL/Christiane Baldwin except files Adobe Stock/Кирилл Журавл and circle glass cutter Adobe Stock/Ivandanru (sorted chronologically or according to the order of the images used in the buying guide)