We have a correction for "A Glassblower's Companion," on page 106, first paragraph, where we have a numeric mistake. The text reads "The venturi mixer operates on low pressure propane (6" w. c. i.) with a #18 orifice." Please correct the text to read "with a #54 orifice."
This is a really large hole as was pointed out by Desmond Crooks of Eugene, Oregon. Thanks, Eugene. I have posted a new page about this pipe heater www.joppaglass.com/pop_off/warmer.html
| Natural Gas | 6" WC | #48 Orifice |
| Low Pressure Propane |
8"‚11" WC | #54 Orifice |
| High Pressure Propane |
1-2 psi You will not need much pressure Use needle valve to modulate gas flow |
#65 Orifice |
The orifice I have in my shop burner is a #65 and it works great. I find the square tubing works a lot better than the round pipe that I originally used in the pipe warmers we made for Haystack School. Dudley