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best torch for glass blowing

Best torch for glass blowing

The gases commonly used for working borosilicate glasses are propane or natural gas mixed with oxygen. It is important when selecting your burner, torch and tips that they be designed for use with these gases. Units designed for gas/air mixtures should not be used with gas and oxygen.

A typical glassblower’s burner. Burners are usually bench or lathe mounted. The bench burner shown here has two gas and two oxygen valve controls, offering a wide variety of flame configurations. The aluminum collar shown mounted on the burner barrel aids in heat dissipation.

Another example of a glassblower’s bench burner. The two inner valves (green = oxygen and red = gas) create a relatively small tight flame. Opening the two outer valves offers the glassblower a much larger flame as shown here.

In use, burners are usually stationary or mounted as part of a fixture. The glass is brought into the flame where it is heated and manipulated by the glassblower.

Lathe burners are mounted on a movable carriage. The four (4) jet burner pictured can be moved up or down to match the diameter of the glass being worked or rolled back and forth along the length of the glass tubing using the carriage. Each burner jet angle may be adjusted as well.

Glassblowing torches are usually smaller and much lighter than burners or burner assemblies. The torch shown here is a pre-mix (gas/oxygen are mixed in a chamber within the torch body) style quite popular with many glassblowers.

Pre-mix torches often have removable tips in a wide range of sizes, providing a number of flame options to the glassblower.

Torches are brought to the glass, which is held stationary by clamps or other fixtures. The size, weight and balance of a torch are important features to the glassblower.

Torches and burners come in a variety of shapes, sizes and capabilities to fill the many applications required by the glassblower. Traditionally, these are made of metals such as stainless steel, brass, etc., however, special needs may require custom fabrication using non-traditional materials. For example, if metal contamination from a hot torch might cause problems in a particular application, one can use a glass (quartz) torch. Additional photos and information may be found at Blue Flame Technology

This page and any associated material is copyright 2002-2020 by Joe Walas and/or ILPI unless otherwise stated. Unauthorized duplication or posting on other web sites is expressly prohibited. Send suggestions and comments (include the URL if applicable) to us by email. CAUTION: Be sure to read this important safety/legal disclaimer regarding the information on this page.

A discussion of burners and torches at The Scientific Glassblowing Learning Center

Best torch for glass blowing

Pre-mix torches as a rule are capable of burning a little hotter with a flame that can be very concentrated. Gas and oxygen are mixed in a chamber within the torch body. This style torch is preferred when making seals and/or when heating small concentrated areas. If you were to be restricted to using only one torch, the pre-mix is recommended. Premix torches have the benefit of having interchangeable tips, allowing the user the option of changing flame characteristics over a broad range. A torch used quite extensively in the industry is the National Handtorch Type 3A Blowpipe shown here. This relatively inexpensive torch, with tip sizes #2, 3, 4,and 5 will cover most of your needs.

Surface-mix torches and burners are used most frequently when large areas of glass need to be worked. Oxygen and fuel gases are mixed at the torch tip. The flame characteristics tend to be broader and softer, with less velocity than a comparable sized flame from the pre-mix torch. This is a good torch to use when preheating a large piece of glass apparatus for repair, or when shaping large tubing. An excellent example of a burner that incorporates surface-mix and pre-mix capabilities would be the Carlisle CC Burner.

There are many other makes and models of burners and torches available to the glassblower. Their different flame and body characteristics determine their application in the glassblowing field.

Torches (handheld) may be used as burners by simply hanging or attaching them to some sort of fixture. This fixture may be something as simple as a ring-stand and clamp assembly or a custom made unit that will hold the torch in a safe and secure manner.

Before you start

Review all safety procedures before you plan or start your work. Think out what it is that you will be doing and know what action to take if something happens different than expected. Read through the instruction text to prepare for the exercise. It is best to avoid surprises at this stage of instruction!

Light up

  1. Confirm gas delivery systems are in safe operating condition. Set the regulator at 5 psi gas and 10 psi oxygen.
  2. Open the gas valve one full turn to purge air from the line and then quickly close the valve.
  3. Repeat step #2 with oxygen.
  4. Open the gas valve approximately 1/4 turn and then ignite the gas with your flint lighter.
  5. The torch is lit! Adjust the gas valve to produce a flame about 3/4″ long. This is known as a pilot flame. You may leave the torch flame at this position when not in use – but always attended.
Tip: If you experience difficulty in immediately igniting the gas beware of excessive gas buildup. Shut the gas valve off and wait a few minutes to allow the gas to dissipate. Attempt to light the torch again using a different setting on the gas valve.

Adjusting The Flame Size

  1. Gas first – open the gas valve to create a flame length about 6″ long (about the length of your hand). The flame should be still attached to the torch tip. If there is a space greater than 1/8″ between the flame and torch tip adjust (close) the gas valve until the flame “re-attaches” to the tip.
  2. Slowly open the oxygen valve. Observe how the flame changes in shape, velocity and heating characteristics.
  3. Practice flame control by changing the settings on the gas and oxygen valves. Make the smallest flame possible, using an inch long flame as a target. Now attempt to create the largest flame possible. Try different tip sizes to observe the flame size range each produces.
Tip: Take the time to become comfortable handling your torch now. With practice, creating the various flames necessary to produce sound glassblowing seals will become second nature

    If the torch should suddenly bang or pop as a result of improper gas/oxygen mixing, immediately close the gas and oxygen valves at the torch. Re-open the oxygen valve to flush out the mixing chamber in the torch body, extinguishing any flame that may have flashed back into the chamber. This action only takes about 5 seconds. Close the oxygen valve. The torch is now ready to re-light.

If the flame extinguishes itself (improper gas/oxygen mix) and there is no pop or bang, simply close the gas and oxygen valves and then relight the torch.

  • Flame appears where its not supposed to! A definite safety hazard! Close the supply line valves closest to the torch. Re-check all connections, valves and fittings.
  • Selecting The Correct Flame Size

    Flame intensity is a factor in determining how quickly the glass reaches working point temperatures. Experience will guide you in choosing the proper flame intensity and flame size to apply to the different types of seals. Each person will develop their own style and technique in using the torch. The information presented here should serve as a starting point.

    Shutting Down the Gas Delivery System

    1. Close the valve at the gas source.
    2. Open the valves at the torch and burn off all released gas.
    3. Back off the pressure adjusting screw at the regulator(s).
    Tutorial Lesson 5, Burners and Torches
    Lesson 4
    (Burners and Torches)
    Lesson 6
    (Cutting Glass)

    This page and any associated material is copyright 2002-2020 by Joe Walas and/or ILPI unless otherwise stated. Unauthorized duplication or posting on other web sites is expressly prohibited. Send suggestions and comments (include the URL if applicable) to us by email. CAUTION: Be sure to read this important safety/legal disclaimer regarding the information on this page.

    Page 5 of a 17 page introduction to basic scientific glassblowing techniques at The Scientific Glassblowing Learning Center