Green twin have you watched this video about a burner for cast iron melting? Hmmmmmm there was no cast iron melting and he sounded like a politician in election mode.
I think I have touched on the "youtube burner guys" before, but it is worth noting again.
There are profession youtube "burner guys", and "ingot casters" (olfoundryman has some other terms for the ingot guys, which I will not repeat, but it has to do with polishing things).
It is not my place to tell people how to have fun, and so its all good as far as I am concerned, but not necessarily all good if you are trying to find a reliable foundry burner.
Generally speaking, the quantity of videos and view count for the burner and ingot guys is directly proportional to the usefulness of their content, ie: the more videos they have, and the higher the view count, the less useful it seems the information they offer is to a typical backyard casting person.
There also seems to be a correlation between the size of the flame from their burner and how useful the burner is, ie: the bigger the flame they are shooting out the end of the burner, the less useful it is for foundry work. A good foundry burner may not operate well at all if it is not inserted in the furnace opening (the opening in the furnace for the burner tube is called the tuyere, pronounced "tweer" I think).
There are a number of what I consider "junk" burners on youtube, and by "junk" I mean not useful for foundry work, or not reliable for long term foundry work. These burners may have other useful purposes.
How to tell if a burner is not useful for foundry work:
1. The burner tube gets red hot during operation. Red hot burner tubes do not last very long, even if made with stainless steel.
There is no reason to operate a red hot burner tube or burner for foundry work.
2. Used car salesman shrill pitches about burners that seemingly will do just about anything, including powering a Saturn V rocket are useless burners for foundry work in my opinion.
3. "Better mouse trap" burners are generally some unique twist to a standard foundry burner, to make a better mouse trap, but these burners in my opinion add useless gimicks to a burner that serve no purpose, and often give a burner that degrades over time. Some burner types appear to be outright dangerous, such as those using high fuel pressure.
4. High velocity burner outputs are not useful for foundry use. The high velocity flames just climb up the back of the furnace to the lid, instead of swirling around the crucible and transferring heat to the crucible.
5. BIG burners are not better for foundry use. I have tried some big burners, and they actually run cooler than the smaller ones.
The secret to operating a very hot burner and furnace is to introduce exactly the amount of combustion air and fuel into the furnace that a given size of furnace can completely combust, and making sure that complete combustion occurs INSIDE the furnace around the crucible.
Excess fuel and/or combustion air cools a furnace.
Bigger is definitely not better in the foundry burner world.
6. Burners that preheat the fuel like a Coleman gas stove burner does are not useful for foundry work. Running a fuel line through a hot part of the burner or furnace just cokes up the tube, and clogs it. There is no need to preheat fuel for a foundry burner unless you are running thick waste oil in the winter.
7. The Ursutz burner is what I call a "precombustion chamber" burner (not sure if that is an official term or not).
The Ursutz burner uses a chamber outside of the furnace, and the fuel is combusted in the chamber, and then piped into the furnace.
I have tried an Ursutz burner, and they get red hot when operating, and degrade quickly over time.
The Ursutz burner is reported (by someone who has used one a lot) to be easily capable of destroying crucibles due to producing too high a temperature inside the furnace, when the burner is operated at its maximum.
The Ursutz burner is also said to be capable of degrade the plinth quickly.
Given all of the problems that Ursutz burners cause, I can't think of any reason for using one for foundry applications.
8. It should be noted that some videos show burners that are not installed on a tangent to the side of the furnace, and thus the burner flames impinge upon the side of the crucible.
The crucible should never have direct flame impinging upon it, else it will fail very quickly.
BIG burner/BIG flame videos are great entertainment, but are not useful for foundry applications, in my opinion.
The burner types that have been demonstrated to work well for foundry work, that I have seen are:
1. The drip-style oil burner, which I hate, but others love.
2. The siphon-nozzle burner, or its cousin the pressure-nozzle burner.
I use a siphon-nozzle burner, and will soon be converting to a pressure-nozzle burner so that I don't need compressed air for atomizing the fuel.
3. The propane burner works well for aluminum melts, some brass/bronze melts, and even cast iron melts, if you have a high pressure/high flow regulator, and if your tank does not get so cold that it will not longer vaporize.
I use propane burners for aluminum only to avoid the cold tank/low pressure problem.
4. The Ursutz burner can I guess be argued about.
I know of one individual who has used an Urstuz for years to melt iron, and he likes it.
I would not go so far as to consider the Urstuz a good foundry burner, but I can't deny that this individual has melted perhaps a thousand pounds of iron (or more) using his Urstuz.
He has also had a lot of problems with his Ursutz, and problems caused by his Urstuz, which he just tolerates for whatever reason.
He sees lots of burner and furnace rebuilds which I think can be attributed to the Ursutz, which to me is totally unnecessary, and wasted time and money.
At the risk of sounding like one of those angry old gray haired guys who shouts at the schoolchildren "GET OFF MY LAWN !!!! ", I offer the following thoughts:
Rube-Goldberg style burners are not useful for foundry work, in my opinion, although they may be impressive to observe.
Many (perhaps most) burners on youtube are what I consider Rube-Goldberg style burners.
Millions of views, thousands of subscribers and likes, hundreds of videos, totally useless burners for foundry work.
Many burners on youtube are better classified as flame throwers I think, so perhaps they could serve some useful purpose.