ColdHeat
Encyclopedia
Property
Property is any physical or intangible entity that is owned by a person or jointly by a group of people or a legal entity like a corporation...
graphite
Graphite
The mineral graphite is one of the allotropes of carbon. It was named by Abraham Gottlob Werner in 1789 from the Ancient Greek γράφω , "to draw/write", for its use in pencils, where it is commonly called lead . Unlike diamond , graphite is an electrical conductor, a semimetal...
-like compound Athalite. The composite material is claimed by the manufacturer to have the unusual ability to conduct large amounts of heat
Heat
In physics and thermodynamics, heat is energy transferred from one body, region, or thermodynamic system to another due to thermal contact or thermal radiation when the systems are at different temperatures. It is often described as one of the fundamental processes of energy transfer between...
and return to room temperature in a short amount of time.
Soldering iron
Soldering iron
A soldering iron is a hand tool most commonly used in soldering. It supplies heat to melt the solder so that it can flow into the joint between two workpieces.A soldering iron is composed of a heated metal tip and an insulated handle...
s. The manufacturer claims this soldering iron is unique in that its Athalite tip undergoes a temperature change from ambient temperature to approximately 800 °F (426.7 °C) and back to ambient within three seconds when the tip is removed from the work.
The tip of this apparatus is split into two sections that completes an electrical circuit when something of low resistance is placed across the tip; e.g. solder. With a current flowing, the resistance of both the solder and the tip produces heat and causes the solder to heat up and flow. For light duty work it was designed for, the Athalite tip barely warms at all and can thus cool very rapidly; however if the user attempts to solder things beyond the ability of the iron, this absorbed heat can make the tip very hot and it can take over a minute to cool in some cases.
The original iron is powered by 4 ordinary AA (LR6) alkaline batteries
Alkaline battery
Alkaline batteries are a type of primary batteries dependent upon the reaction between zinc and manganese dioxide . A rechargeable alkaline battery allows reuse of specially designed cells....
for portability and is capable of melting solder up to 18–20 gauge
American wire gauge
American wire gauge , also known as the Brown & Sharpe wire gauge, is a standardized wire gauge system used since 1857 predominantly in the United States and Canada for the diameters of round, solid, nonferrous, electrically conducting wire...
. The second iron is powered by 5 AA alkaline batteries, to give it more watt
Watt
The watt is a derived unit of power in the International System of Units , named after the Scottish engineer James Watt . The unit, defined as one joule per second, measures the rate of energy conversion.-Definition:...
age.
The soldering iron has a built-in light. The direct marketing
Direct marketing
Direct marketing is a channel-agnostic form of advertising that allows businesses and nonprofits to communicate straight to the customer, with advertising techniques such as mobile messaging, email, interactive consumer websites, online display ads, fliers, catalog distribution, promotional...
campaigns are geared toward occasional users who may lack soldering experience and to whom safety is important.
The device works by running a high current (by electronic standards) through the tip. Running a high electric current through sensitive parts inadvertently may not be a good idea in certain instances, for example, when soldering electronics. When not in contact with a joint the split tip has 6 volts (7.5 volts for the second iron) across it, easily enough to destroy semiconductor
Semiconductor
A semiconductor is a material with electrical conductivity due to electron flow intermediate in magnitude between that of a conductor and an insulator. This means a conductivity roughly in the range of 103 to 10−8 siemens per centimeter...
p-n junction
P-n junction
A p–n junction is formed at the boundary between a P-type and N-type semiconductor created in a single crystal of semiconductor by doping, for example by ion implantation, diffusion of dopants, or by epitaxy .If two separate pieces of material were used, this would...
s on contact if the iron accidentally touches multiple closely spaced pads . This has nothing to do with static-electricity damage
Electrostatic discharge
Electrostatic discharge is a serious issue in solid state electronics, such as integrated circuits. Integrated circuits are made from semiconductor materials such as silicon and insulating materials such as silicon dioxide...
; a forward-biased p-n junction may be destroyed by less than 1V applied across it unless the current is limited to only a few tens of milliamperes, which ColdHeat does not do and could not operate if it did.
Some people debate whether the heat actually comes from the resistance of the tip or from the resistance in the solder. As one ColdHeat engineer said:
It’s a common misunderstanding that high current in the joint causes the heat. The heat is generated by resistance within the tip. Heat is then conducted to the joint just as in traditional solder tools. Also, current in the joint is limited to the small region between the two tip halves and doesn’t pass through the part being soldered. There is a tiny transient voltage when the tool is applied or removed, but it is orders of magnitude below the levels that cause static-electricity damage.
Criticism
Common criticisms include that the tip is very fragile and therefore easily damaged, the unit doesn't have enough power for effective desoldering of many board-mounted and chassis-mounted components, and that the design of the tip is incompatible with some soldering techniques such as continuous flow soldering (a popular technique for hand-soldering high-pin-count SMTSurface-mount technology
Surface mount technology is a method for constructing electronic circuits in which the components are mounted directly onto the surface of printed circuit boards . An electronic device so made is called a surface mount device...
packages, based on the principles of wave soldering
Wave soldering
Wave soldering is a large-scale soldering process by which electronic components are soldered to a printed circuit board to form an electronic assembly. The name is derived from the use of waves of molten solder to attach metal components to the PCB...
).
One thorough review http://www.epemag.wimborne.co.uk/cold-soldering2.htm of the ColdHeat soldering iron has noted:
- "For the electronics hobbyist, one particularly disconcerting side-effect of the Coldheat way of doing things is that localised arcing and sparking may be produced sporadically when the heating circuit opens or closes. ... sparks anywhere near a semiconductor are an anathema to the electronics enthusiast. High reverse voltages can be produced in inductive circuits as well. ..."
- "The overall results of the soldering exercise were very disappointing. ... the test results on the p.c.b. were of extremely mixed quality. ... The quality of the soldered joints was extremely inconsistent, due to the lack of temperature control and other variables that affect the finished joint. ... perhaps 20% of the finished joints being of a reasonably good standard... It was difficult to feed solder onto the joint at a consistent rate because the heating effect was variable. ...The dull crystalline appearance of many joints points to inadequate heating, caused by the heat not sinking throughout the joint sufficiently to melt the solder thoroughly, before the iron was removed. Although a grey crystalline joint will often form a sufficiently working joint for non-critical applications, the circuit might have an intermittent fault because of this. ..."
- "There is ... no escaping the most fundamental principle of soldering: in order to make a good quality solder joint, all parts should be heated to the melting point of the solder so that it can flow properly. In the case of "cold-soldering" a p.c.b. (such as our Velleman kit), then only one half of the joint can effectively be heated by the iron, e.g. a cropped resistor lead that you use to short out the electrodes to generate heat. Solder can then melt onto the hot leadout but it is then forced to flow onto the other component (the p.c.b. copper pad) which is completely cold. Inadequate through-heating of components is the main cause of dry (gray) solder joints. What little heat there is, sinks away through the workpiece and the solder never flows properly. A crystalline, dull and brittle joint is formed. ...with our test circuit board... three p.c.b. copper pads were damaged by excess heat, causing the copper track to lift away from the laminate altogether. ... Unfortunately we failed to finish and test our sample board successfully, due to the damage caused to three copper pads."
- "... With just a little practice with an ordinary electric iron ...it is perfectly possible for any novice or hobbyist to produce good quality consistent results ...that are superior – and faster – than the Coldheat principle. ..."
- "Unfortunately, I can’t recommend the Coldheat Soldering Iron to the average electronics constructor unless they are extremely accident-prone, lacking confidence or have a real need to go cordless: they should save money and buy an ordinary electric iron instead. ...Users stand a much better chance of producing a higher quality and more consistent solder joint with an ordinary iron using accepted techniques... ."
Athalite
Athalite is a highly malleable, yet fragileFragile
Fragile may be an adjective meaning brittle.It may also refer to:-In albums::*Fragile , 1971*The Fragile, a 1999 album by Nine Inch Nails*Fragile , 2000*Fragile , 2000...
, composite material
Composite material
Composite materials, often shortened to composites or called composition materials, are engineered or naturally occurring materials made from two or more constituent materials with significantly different physical or chemical properties which remain separate and distinct at the macroscopic or...
. The name is derived from "Accelerated THermal Action". It is most likely composed of graphite. It might also be formed by other materials containing semiconductive elements such as germanium
Germanium
Germanium is a chemical element with the symbol Ge and atomic number 32. It is a lustrous, hard, grayish-white metalloid in the carbon group, chemically similar to its group neighbors tin and silicon. The isolated element is a semiconductor, with an appearance most similar to elemental silicon....
or silicon
Silicon
Silicon is a chemical element with the symbol Si and atomic number 14. A tetravalent metalloid, it is less reactive than its chemical analog carbon, the nonmetal directly above it in the periodic table, but more reactive than germanium, the metalloid directly below it in the table...
, as stated in the patent
Patent
A patent is a form of intellectual property. It consists of a set of exclusive rights granted by a sovereign state to an inventor or their assignee for a limited period of time in exchange for the public disclosure of an invention....
application. A nickel
Nickel
Nickel is a chemical element with the chemical symbol Ni and atomic number 28. It is a silvery-white lustrous metal with a slight golden tinge. Nickel belongs to the transition metals and is hard and ductile...
-chromium
Chromium
Chromium is a chemical element which has the symbol Cr and atomic number 24. It is the first element in Group 6. It is a steely-gray, lustrous, hard metal that takes a high polish and has a high melting point. It is also odorless, tasteless, and malleable...
or other resistive
Electrical resistance
The electrical resistance of an electrical element is the opposition to the passage of an electric current through that element; the inverse quantity is electrical conductance, the ease at which an electric current passes. Electrical resistance shares some conceptual parallels with the mechanical...
alloy
Alloy
An alloy is a mixture or metallic solid solution composed of two or more elements. Complete solid solution alloys give single solid phase microstructure, while partial solutions give two or more phases that may or may not be homogeneous in distribution, depending on thermal history...
is another possibility listed in the application, but is unlikely to have been used.
Other products
Prior to the website's closure, ColdHeat featured products other than the soldering tool that use the same technology, including a cordless hot-melt glue gun called Freestyle. It heats up much more quickly than others (but not instantly like the solder tool.) It comes with a built-in stand, a pack of mini glue sticks, rechargeable battery, battery charger with its AC adapter, and an instructional manual and a book with different project ideas. However, much like the soldering tool, the Freestyle also had quality issues, usually related to the battery charge, and the heating element. There is a model that runs on AA batteries, for those who prefer their convenience.ColdHeat had recently released a cordless heated seat, as well as a selection of heated pet beds.