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Old 2016-07-02, 8:59pm
De Anza Art Glass Club De Anza Art Glass Club is offline
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Join Date: Nov 24, 2009
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Ed Hoy sells Art Glass products. The shop used to be wholesale only, but I see that they have recently added retail sales. The Hot Head is sold by many retail outlets, but there are also substitutes available. Judging by the price on the Ed Hoy site, it is likely that you have an official Hot Head, but that is not guaranteed.

The Hot Head started out as a common hand held torch. There is a person on LE who claims there is no difference between the Hot Head and this common torch because they appear identical on the outside. In my experience, there is a difference between the common torch (available for as low as $9.99 a few years ago), and that is with the internal orifice plate. At the least, the difference is that the official Cindy Jenkins Hot Head has a mesh screen filter attached to the orifice plate. All the official Hot Heads that I have seen also have a recessed orifice. These orifice plates used to be sold on the official Hot Head site, but are no longer offered. This seems to correspond with the disappearance of the cleaning instructions, replaced by a caution not to disassemble the torch.

The original torch (not speaking specifically about the Hot Head modification) is designed to screw onto small 1 pound (~450 g) bottle for portable uses such as brazing plumbing lines. The disadvantage of using the 1 lb. bottles has been mentioned (post #11). Many lampworkers minimize this problem and also reduce the cost of the fuel by using bulk tanks. This is done by using a bulk adapter hose, which is a standard item, by which I mean that both the fitting to the bulk tank and the fitting to the torch are standard. I mention this because there are people who insist that this practice is dangerous and against the original design of the torch. I, myself, do not subscribe to that theory, but can give you a link if you really want to read it. These bulk adapter hoses are commonly about 1 meter long, but are also available in long lengths if you are working indoors and have the tank outside.

The common bulk tanks are for propane. Many lampworkers use propane with Hot Head torches. Bulk tanks for MAPP-Pro or propylene are not common and usually must be taken to a industrial gas supply (AirGas or the like in the U.S.) to be refilled. So, I would guess that most lampworkers using the Hot Head use propane.

One effect of having the filter before the orifice is that the gas flow is slightly reduced. Anecdotal evidence is that some lampworkers have found that the official Hot Head has a slightly reduced flame temperature than a standard brazing torch sold as a hot head. http://www.devardiglass.com/Torches.htm

One advantage of the older Hot Heads (no longer available) is that the shutoff valve had better throttling characteristics. Some valves are so finicky that they will only let you operate at near full throttle. One way to solve this is to purchase a throttle valve (valve with finer metering characteristics) and install it upstream of the Hot Head with the Hot Head valve fully open. A better option, when using a bulk tank, is to use a standard gas regulator, such as you will when you get a fuel-oxygen burner, and run the Hot Head at reduced pressure. The reduced pressure is alluded to above (post #10), but if you're interested, I may be able to find a reference. Again, there are opinions that state this is inherently dangerous because it goes against the "design" of the plumber's torch or Hot Head (i.e., the belief is that they are intended only to be used with a portable 454g tank). I, myself, do not believe that to be valid, but it is a written opinion.

The following is opinion and not fact. (Well, there are some facts, but since I don't give references, you can treat them as opinion.) There is a limited range in which the gas and air combination is combustible, and the Hot Head or plumber's torch are not very adjustable. Some people have found that if it is difficult to light the torch, one solution is to cover the holes with metal foil. (Some people might also do this to create a more reducing flame.) Other times, if the pressure is high, too much air can be entrained through the air ports (actually, this is just a restatement of the previous), and the mixture is not right and the torch can blow out (too much fuel for the flame). If the pressure is too low, sometimes flames come out the air vents. Anyway, what I am trying to say is that you might solve your problem and make the torch operation more reliable (and adjustable) by using a regulator at about 4 bar. (So, just repeating and emphasizing post #10 for the regulator.) A high range regulator is less expensive than a welding regulator and should be available at the shops and websites that sell propane equipment. (Not mentioning any here since you are in Asia ... well, on second thought, I will provide a link so you know what I'm talking about https://propanewarehouse.com/product...le-regulators/ . Even though 60 psi is what I'd recommend as a working pressure, you want your set pressure somewhere in the middle of the range, so I'd get a 0-100psi, 0-6.5 bar regulator, not the 0-60psi, 0-4 bar.)
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