Soldering-Types And Their Uses.
Soldering is the joining of metal surfaces or edges with solder.There are two types of soldering;which includes the soft soldering and the hard soldering.
This is when the solder melts below the red hot temperature of the soldering iron.
In hard soldering the solder melts at or above red heat and you can as well call this type of soldering brazing.
TOOLS AND MATERIALS NEEDED FOR SOFT SOLDERING
The materials or tools below are needed to successfully carry out soft soldering:
- Soldering copper
- Soft solder
- Heat source
The soldering bit sometimes called soldering iron,is a square piece of copper pointed at one end and fastened to a steel bar with a wooden handle on the other end. Soldering bits are in various sizes,depending on the nature of the work or job to be done.Heavy copper is used in heavy works or jobs,while light copper is used in light works or jobs .Soldering coppers could either be heated electrically or by the use of burners.
types of soldering bits
In soldering bits,there are two common patterns of used;they are:
- Straight soldering bit
- Hatchet soldering bit
Incase you don’t know what bits are,they are made from copper.Copper is an excellent conductor of heat and also solder and copper have a great affinity when the solder is in its molten state.
straight soldering bit:
The straight soldering bit is used for general work,and for getting into restricted places that are not easily accessible.
The hatchet soldering bit is used for making long joints because of its blade-like edge.It is also used for soldering in grooves.
Solder is the material used in its molten state for the joining of metals.The best soft solder is an alloy or metal made of lead and tin. Solder is used for general work.It is usually made of one-half lead and one-half tin. It is sometimes called half and half or fifty-fifty. Solder must have a lower melting point than the metals to be joined so that they can melt at about 230 degrees celsius. Solder bits are in long bars and also in wire form on spools.
There is a form of solder known as special solder which is used for soldering aluminium; remember that aluminium requires more heat to melt than solder made of lead and also tin. Commercial paste-type solder is used on various metals. Plumbers use it to sweat solder joints and fittings on copper tubes. On the other hand,silver-tin alloy which has a low melting point is used for soldering stainless steel.
Flux is the substance applied on metals to be joined so that the surfaces of the metal can be cleaned. Flux cleanses the metals and helps the solder to flow. Flux makes metal surfaces chemically clean and stops corrosion,permitting the solder to stick tightly to produce good joints. Ready made flux in liquid,crystal and paste forms can be used for ordinary soldering.
Make sure that after soldering,you wash the job or work with water to stop the acid in the flux from eating the metal.
There are mainly two sources for heating the soldering bit. The first is to heat it electrically;here all that is required is to plug the bit cable into an electricity socket and allow it to heat up for some time. You can as well use another source of heat from blow lamps,though this depends on the size of soldering bit to be heated. Blow lamps use paraffin(kerosene) as fuel. There are also stoves specially made or designed to heat soldering bits quickly and economically.
Cleaning up the soldering bits is called tinning the bit. The first thing to do during soldering operation is to clean up the soldering bit and the parts to be soldered. When tinning the bit,clean the point thoroughly with a file,head the copper or bit till the flame turns light green,dip the heated point into flux,rub a stick of solder over the bit;giving it a thin coating all around.
For you to carry out a successful soldering,you must follow these following steps:
- tinning the bit
- cleaning the metals
- holding the work(metals to be joined)
- the art of good soldering
- tacking a seam with drops of solder
HOW TO CARRY OUT SOFT SOLDERING OF A JOINT
- You have to select and clean the parts to be soldered in such a way that they cannot move. If it is possible for you,clamp the joint.
- Make sure that you apply flux to the cleaned parts to be soldered.
- You will have to re-heat the area with the soldering bit. Also re-heat the bit and place it over the seam and apply the solder to the edge and at the same time to the scam,allowing the solder to flow between the parts.
- When the solder has hardened,wash off the flux with water under the tap.The parts to be joined may also be tinned in advance.Then press together the parts to be joined,drawing the heated soldering bit along them so that the coating of solder is melted and the parts are joined.
OTHER TYPES OF SOLDERING
Yes there are other types of soldering.They are sweat soldering and hard soldering.
The sweat soldering is used when it is convenient to use the soldering bit. In sweat soldering,the heat is applied to the pieces to be joined and the solder is melted by this heat. As it melts,the pieces of solder form balls,then flow along the joint. However,the surfaces or edges to be joined are first cleaned. Then flux is applied a little on the surfaces. Small pieces of solder are placed and then heat is applied on the parts until the solder melts and joins the parts together.
Hard soldering is used where a stronger joint is needed or where the parts will afterwards have to be in greater heat than the melting point of soft solder. The most widely used hard solder types are the silver and silver-alloy solder. Most of them melt at temperature from 735 degree celsius to 890 degree celsius. Hard soldering is used for joining metals like copper,silver,gold in jewelry and art metalwork. It can be used on all carbon and alloy steels. It is also used to join band blades.
HOW TO CARRY OUT HARD SOLDERING
- Carefully clean and arrange the parts to be joined.
- Then apply flux,the type recommended for silver soldering is when the parts to be joined are silver materials.
- Then place pieces of silver solder on the joint.
- Heat the parts until the solder melts and runs into the joint and fastens the parts. Heat for hard soldering is usually applied directly from the flame or torch to the parts to be joined.
Brazing is a type of hard soldering which uses filler rods to join the metals together. Brazing is done at a higher temperature than that of soft soldering. It is used on joints that need to be strong and have to withstand heat. Like in soft soldering,flux is used in brazing;the appropriate flux being borax. The heat which should be bright red is usually supplied by an oxyacetylene blow-pipe.
procedures for brazing
- Select and clean the materials or joints to be brazed.
- Apply flux on the surfaces to be joined with the correct flux.
- Arrange the surfaces to be joined with a reasonable gap allowed.
- Apply a rod to the work and heat with the acetylene tank nozzle until the rod melts and flush into the joint and fastens the parts.
safety precautions during brazing
- Avoid inhaling fumes by not leaning over too close to the brazing spot.
- Brazing should always be done in a well ventilated room so that the fumes from molten flux are dispersed quickly.
- Flux should be handled with great care.It should not touch the skin or eye.
- Then as soon as brazing work is finished,the hands and fingernails should be scrubbed clean.