Yes, the MAPP flame in those torches (I have three or four of the comparable model with the flame adjustment valve) becomes hot enough to melt brass; but, it is insufficient to braze anything larger than thick steel wires. As previously noted, the torches are useful for a variety of tasks, including silver soldering tiny items, and the MAPP gas is a better alternative than propane for larger work; IIRC, Rick V posted a comparative thread demonstrating the benefit.
Is it possible to braze using a MAPP torch?
It is determined by the size of the weldment as well as the torch. For little jobs like brazing on a nut or a tab, it should be fine. Some of the newest “turbo” or “swirl” torches are far hotter than older models.
Is map gas suitable for brazing?
Mapp gas works fine on small lines like 3/8 ” and as long as you’re not in a spot where heating for an extended period of time will cause a problem it works O.K. on bigger lines like 5/8″ and 3/4″. When I didn’t have access to an acetylene or oxy/acet torch, I sweated in a lot of condenser units with Mapp gas. I still have extra Mapp gas on hand in case I run out of acetylene or oxygen during a job, especially on a weekend. I wouldn’t try to do an RV with Mapp gas, but you can get away with it for most household tasks.
Is it possible to braze copper with MAPP gas?
We utilize MAPP gas with a shield, which works well up to 7/8 copper tube only, and the braze joint must be kept away from any huge bulk of metal because heat can be pulled away almost as quickly as it is applied.
Is it possible to braze with a gas torch?
Can I use a propane torch to weld aluminum? Yes, you can use a propane torch and aluminum brazing rods to weld aluminum if it’s for non-structural metals that aren’t weighted, strained, or important sections.
Propane torches do not typically reach high enough temperatures to accomplish successful aluminum welding.
Propane can be used to braze an aluminum alloy with smaller dimensions or for non-critical patches or repairs, but it is not advised for aluminum welding.
For aluminum welds, any welding procedure that uses a flux, such as stick welding or flux-cored arc welding, is ineffective. These approaches produce welds that are too porous for a proper weld.
The amount of BTUs a gas flame can concentrate in a concentrated work area is more important than the temperature of the flame.
Despite the fact that propane flames can reach temperatures twice as high as aluminum’s melting point, aluminum’s characteristics make it highly conductive and radiant in heat.
Although some welders believe that repair rods are adequate, their melting points are lower than the melting points of aluminum, making a proper weld unlikely. This is especially important for key things that are under a lot of weight or pressure.
Shielding the weld puddle from impurities is one of the most important aspects of aluminum welds, and shielding gas is essential for this.
There’s a reason why experienced welders invest in expensive aluminum-specific technology. Why would they spend the money if welding aluminum was as simple as some claim?
What kind of torch is required for brazing?
The fuel gas (acetylene, propane, or natural gas) can be burned with air, compressed air, or oxygen, depending on the temperature required for your assembly. Torches with several points or flames can be employed by shifting the flame constantly to diffuse the heat uniformly throughout the assembly and avoid localized overheating, which can damage the joint’s strength. Depending on the assembly that needs to be welded, these are the various equipment procedures.
- You’ll want to utilize torches with the lowest heat and flame temperature for brazing small components and thin sections. The air-natural gas and air-acetylene torches are employed for these applications.
- Oxygen with natural gas, or other gases such as propane or butane, produce good results in many brazing applications. Although these provide a greater flame temperature, for best results, brazing should be done with a slightly decreased or neutral flame.
- Because it operates at a lower temperature, the oxyhydrogen torch should be used to braze aluminum and nonferrous alloys (metals that do not contain significant amounts of iron).
- Flux-covered or cored filler metal rods are required for torch heating to fill in joints of your assembly. The moderate flame temperature of natural gas is ideal for this approach because it decreases the risk of scorching the joint and metal filler. Only copper-phosphorus fillers, which are employed in brazing in the absence of flux, are self-fluxing. Fluxes, on the other hand, are required for all other filler metals. As the joint is prepared for brazing, the filler metal can be preplaced or face-fed into the joint. Remember that torch brazing procedures for oxyfuel gas welding differ from those for oxyfuel gas welding.
- Without automation, manual torch brazing is a basic method. This method is generally used for assemblies with sections that are not all the same size. Only the braze joint is visible, because it is the only part of the body that receives direct heat. The torch in question features a single tip, which is commonly used to control single or multiple flames. If you need to make a large number of assemblies, a mechanical option can be set up to move the assembly components, the torches, or both during the brazing process.
Is it possible to braze aluminum with map gas?
Due to the heat dissipation of aluminum, propane or MAPP gas without an oxygen feed will not function on aluminum boats. To guarantee a proper connection, clean the metal with an abrasive such as a sanding disk or wire wheel before beginning your brazing operation.
What is the temperature at which you braze steel?
Steel braze welding requires just a temperature of roughly 9000C, rather than a temperature of more than 15000C. The time and gas savings may often be sufficient to compensate for the filler metal’s significantly higher cost.
For brazing steel, what kind of rod is used?
A material designed specifically for braze welding, such as 25M bronze welding rod, is an example. It tins easily, flows freely, and makes weld metal with great ductility and strength.
Is MAPP gas hotter than acetylene?
Because of its high flame temperature of 2925 C (5300 F) in oxygen, genuine MAPP gas can be used in conjunction with oxygen for heating, soldering, brazing, and even welding. Although acetylene has a higher flame temperature (3160 C, 5720 F), MAPP has the advantage of requiring no dilution or special container fillers during transportation, allowing a larger amount of fuel gas to be transported at the same weight, and it is considerably safer in use.
Due to the high concentration of hydrogen in the flame (greater than acetylene, but lower than any of the other petroleum fuel gases), a MAPP/oxygen flame is not totally suitable for welding steel. The hydrogen corrodes the welds by infusing itself into the molten steel. This is not a severe concern for small-scale MAPP welding because the hydrogen escapes rapidly, and MAPP/oxygen can be utilized to weld small steel pieces in practice.
Underwater cutting, which necessitates high gas pressures, MAPP/oxygen was shown to be beneficial (under such pressures acetylene can decompose explosively, making it dangerous to use). Underwater oxy/fuel gas cutting of any kind, on the other hand, has mostly been supplanted by exothermic cutting, which is faster and safer.
MAPP gas is also utilized in air combustion for brazing and soldering, where its higher combustion temperature of 2,020 C (3,670 F) in air gives it a modest edge over rival propane fuel.
The most significant disadvantage of MAPP gas is its high cost, which is typically one-and-a-half times that of propane at the refinery and up to four times that of propane at the consumer level. It is no longer widely used in large-scale industries. for consumers on a broader scale When high flame temperatures are required, acetylene/oxygen is more cost-effective than MAPP/oxygen, while propane/air is more cost-effective when large amounts of overall heating are required.
A MAPP/oxygen flame, on the other hand, is still extremely desired for small-scale users, as it has higher flame temperatures and energy densities than any other flame other than acetylene/oxygen, but without the hazards and hassles of acetylene/oxygen. It comes in handy for jewelers, glass bead makers, and a variety of other craftspeople. The high heat capacity of the MAPP/air flame is particularly valued by plumbers, refrigeration and HVAC experts, and other craftsmen; MAPP was frequently utilized until recently, and was provided in small to medium size containers.
Blowtorches are used to brown and sear food cooked sous-vide at low temperatures. MAPP gases should be used instead of cheaper butane or propane, according to Myhrvold’s Modernist cuisine: the art and science of cooking, since they create greater temperatures with less chance of giving the dish a gas flavor, which can occur with incompletely combusted gas.
What kind of brazing materials do you use?
Heating the assembly to brazing temperature and pouring the filler metal through the joint is the actual brazing process. When heating an assembly to brazing temperature, be sure it doesn’t reach the melting point of the base materials.
First, apply heat evenly to the base metals during the brazing process. If you’re brazing a small assembly, you can heat it all the way to the brazing filler metal’s flow point. Heat a big area around the junction if brazing a large assembly. To braze a single assembly, most people use a hand-held torch. Natural gas, acetylene, propane, and propylene are among the fuels that can be combusted with either oxygen or air. Keep in mind that both metals in the assembly should be heated evenly to reach brazing temperature at the same moment. Keep the torch moving at all times and avoid directly heating the braze area.
Keep an eye on the flux to avoid uneven heating. The parts are being heated equally if their appearance changes uniformly.
When the assembly has reached brazing temperature, it’s time to add the filler metal. Hold the rod or wire against the joint region with care when manual brazing. The heated assembly will melt a part of the filler metal, which will be drawn instantaneously throughout the joint region by capillary action. To increase the flow, add some flux to the end of the filler metal rod (approximately 2 to 3 inches). You can apply flux to the rod by brushing it on or dipping it in it. Adding fresh flux to the filler metal will help enhance the flow and penetration of the filler metal into the joint region for bigger portions that require longer heating times or if the flux has become saturated with oxide.
Keep in mind that molten brazing filler metal tends to flow toward hotter locations. The exterior base metal surfaces of the heated assembly may be slightly hotter than the inner joint surfaces. Make sure to place the filler metal right next to the joint. It will prefer to plate over the heated surfaces rather than flow into the joint if you deposit it away from the joint. It’s also a good idea to heat the side of the assembly opposite the filler metal feeding point. The filler metal will tend to follow the source of the most intense heat.