OK, comments on the T862++ after some research into its operating principle and the embodiment of such in the unit under discussion
1. The operating principle of using a combination of powerful IR emitting lamp and collimating lens(es) is a proven solution to BGA and SMD soldering and desoldering.
2. The incorporation of specific lenses to suit IC dimensions is both desirable and effective in providing a controlled thermal field and so avoid unnescessary thermal shock or heating to surrounding components.
3. The IR lamps used to generate the Infrared energy are 'tuned' for maximum IR output rather than visible light wavelengths. Their use for this application is both justified and wise so using a common 12V 100W Non dichroic reflector Halogen lamp may still work, but is not an optimised solution.
3. The T862++ incorporates a 600W ceramic 120mm x 120mm lower pre-heating plate. This is considered adequate for the intended use and IC dimensions. The pre-heating of the PCB carrying the IC is very important but pre-heating of the whole PCB is not essential provided care is taken with the localised pre-heating stages. Expansion stresses and thermal shock to components within and outside the are of pre-heating area must be considered.
4. The IR lamp on the T862++ is controlled by a 'PID' in the base unit. The design of the lamp controller is too simple for the intended task and appears to operate much li,e a Microwave oven controller that it injects energy into the target are by simple on/off cycling of the heating source. Such a simple approach may suit heating food but it is far from optimal for heating a delicate IC and PCB. The correct approach would be far more analogue in nature and the IR Lamp PID should provide a PWM output to drive the IR lamp at a level appropriate to both gradually achieve the target temperature on the IC, and maintain it for the required period of time. Further control in the form of a programmable stepped heating and cooling cycle further
Enhances performance. A K type thermocouple should be used to provide the PID with an accurate surface temperature of the IC or PCB. Non contact IR K type thermocouple sensors may be used to further enhance the design. Programmable PWM PID's are now common and relatively inexpensive. Many provide PC control capabilities.
So in summary, the T862++ is a sound mechanical design that uses a proven approach to heating BGA and SMD technology. Its flaws lie in the control of the IR energy source and the IC/PCB temperature monitoring, in fact it provides no such temperature measurement. The unit is clearly 'entry level' and sadly it will easily destroy components if not used with intelligence and care. The on/off cycling of the IR lamp rather than a PWM drive to gently increase and decrease its output is a serious flaw in my opinion. The lamp life is reduced by on/off cycling and thermal shock is induced into the component being illuminated in the IR energy beam. The physical build of the u it appears more tha. Adequate for the basis of a good BGA Rework station working with the smaller BGA IC's. I suspect that PC North and South Bridge IC's dimensions would be the limit of the units capabilities, even after improvements are made to the design.
Am I happy with my purchase ? Yes. Thee are more expensive u its that claim greater performance but those are also lacking in some areas. The IR6000 is an example. It uses a ~400W 80mm x 80mm ceramic IR radiating plate as its IR above decks heat source. Thee is no collimation of the thermal energy leaving that heat source beyond the head casings shape around the ceramic heater. The design appears flawed in this respect but could likely be improved without too much effort.
I will be sourcing a PWM programmable PID for my T862++ and may already have one in stock. As I paid far less than the normal retail price for the T862++ I do not begrudge this small extra expenditure or work as it will make the unit fa.r more useable and will also extend the life of the IR lamp. At £23 each that is a good idea.
Some may wonder why I have made no mention of the soldering iron supplied with the T862++. The reason is that it is the standard cheap and nasty soldering iron available as a soldering station at very low cost. It's performance is relatively poor and it is not well thought of by many users. I do do not intend to even connect it to the base unit. A decent quality soldering iron is highly recommended for any serious electronics work on BGA or fine pitch SMD pins.
Finally, in its ex factory form. The T862++ may work as an IC removal and installation system, but it will easily cook the IC and components that reside within its powerful IR beam. I have watched I. Horror as some You Tube videos show people virtually incinerating BGA chips and PCB's with this unit. All tools should be used with intelligence !
Fraser