1. Torch Comparisons

These comparisons are general comparisons to give flame workers unfamiliar with Bethlehem torches an idea of the torches flame size and heat capabilities.




GTT – Lynx
Carlisle – Mini CC
Nortel – Mega Minor




GTT – Phantom
Carlisle – CC, Black Widow
Nortel – Red Max




GTT – Mirage
Carlisle – CC+
Nortel – Red Rocket




GTT – Kabuki
GTT – Delta Mag

*According to Bethlehem’s flow tests, Bethlehem burners are capable of flowing more O2 than any other torch comparable to its size


2. Bethlehem torches and O2 Concentrators

Often flame workers want to know what size O2 concentrator is needed to operate a Bethlehem torch. This question is complicated to answer because there are many variables when it comes to O2 concentrators and the flame worker’s desired flame size. As long as a concentrator can produce a minimum of 5 LPM at 5 PSI, it can be used on all three Bethlehem torches. If the flame worker wants the torch to produce the largest and hottest flame the torch is capable of producing, the O2 concentrator(s) must produce a minimum of…


10 LPM at 8 PSI


30 LPM at 8 PSI
(10 LPM – center fire, 20 LPM – outer fire)


40 LPM at 10 PSI
(10 LPM – center fire, 30 LPM – outer fire)

The flame worker may accomplish these flows by either using one concentrator capable of producing the maximum flow requirement or linking several concentrators together to reach the maximum flow requirement.


3. Why low pressure?

Skilled flame workers, working production often wonder, “Why bother with low pressure if they are using liquid O2 and have no need for O2 concentrators?” The answer is found in flame stoichiometry. One unit of propane needs 5 units of O2 in order to fully combust. By using larger port orifices and surrounding each gas port with O2, Bethlehem is able to flow the correct amount of O2 to propane for complete combustion. SEE “Why Low Pressure” doc.

The lower pressure not only aids in complete combustion but also produces soft flames that are gentle to the glass while soaking the glass in even heat. This makes the Bethlehem flame perfect for flame workers working glass tubing, performing milli pulls and any work involving difficult colors.


4. Repairs

Generally a torch sent in for a repair or cleaning will be returned within two weeks.

  1. General cleaning – $160.00
  2. Valve replacement- $75.00

Some torches will not be able to be repaired. All torches received for a cleaning or repair will receive a free diagnostics test by our trained staff. Once all the information on the torch is collected, a Bethlehem Burners representative will contact the torch owner and provide a list of recommended repairs and estimate for the repair.

Bethlehem Burners CAN NOT resurface any torch face.


5. Warranty

All Bethlehem burners come with a lifetime factory warranty. If a torch malfunctions due to factory error, the torch will be fixed or replaced at no cost to the customer.


6. Future torch projects

We are currently working on:

  • Surface mix hand torch


7. Loose control valves

Bethlehem Valve Sensitivity Information

Bethlehem Valve Sensitivity Video


8. Cleaning a torch

How far should the wires go into the torch?


9. Humming torch

Sometimes a torch will hum. There are a couple of reasons why.

  1. Old or malfunctioning regulator.
  2. Debris caught in between hypo tubes.
  3. Bent hypo tubes


10. Clicking sound coming from torch

Often this is because of the metals expanding and contrasting when they are heated and cooled. It’s normal.

If the flame jumps when there is a clicking sound or if the torch has been in use for several years and never made the sound but then started making the sound all of the sudden, please call (610) 838-7034 and talk with Kate.