If you get unsoldered pads but you are already hitting peak temperature try to make your profile last a little longer for every phase (while keeping it inside the maximum limits). Of course this is not very practical and you should be ok by following a couple of simple rules: Ideally you should measure temperature over the entire board and across every component to be sure to have a profile with a peak temperature high enough for reflowing but not too high to cause thermal shock on the bigger components. Moreover, since in the toaster ovens the heat is transferred mostly by radiation, remember that bigger black components heats faster than smaller ones. When using a toaster oven this problem can cause some serious issues like pads where the solder paste do not reflow correctly or, even worst, components which overshoots the target temperature.
#Reflow soldering temperature professional
It may be quite difficult, even with big professional ovens, to keep a uniform temperature across the entire PCB. X-toaster comes with a preprogrammed desiccant profile to keep the components at 125☌ for 60/90 minutes.Įven so keep in mind that this is not an ideal process and that micro fractures could be forming. If you have some sensible components sitting in a box for more than a few days you should try to let the moisture in it evaporate gently before attempting any reflow. If you have a lot of components to be soldered in many PCBs during more than one day, always use an ESD safe sealed bag and keep them in it, with the indicator and the desiccant.
This lead to the first rule: only open these packing when you are going to solder them on the PCB and check the indicator that the moisture has not gone over the maximum allowed percentage.
#Reflow soldering temperature cracked
That’s because the moisture in the package when exposed to high temperatures vaporizes and, if you do not give this vapors enough time to exit the package, the result could be a cracked microcontroller. When you order some big microcontroller from Digi-Key or Mouser they usually come in a sealed bag with a humidity indicator and a desiccant pack inside. The first is that some components are sensible to thermal chock and the moisture content of their packages may be an issue. When dealing with reflow soldering there are some things to know which usually are not needed when hand soldering with an iron. X-toaster has been designed to follow any reflow profile, to be adaptable to any oven and to compensate for inertia and hysteresis. These toaster ovens also transmit heat mostly by radiation than convection and this is another factor to take into account when building a controller. Industrial ovens usually costs more than 1.000 USD and the cheaper Chinese alternatives on the market (which still are quite pricey, around 400/500 USD) are simply too buggy and do not have a build quality good enough for a reliable (and secure) use.Ī toaster oven conversion is usually a much cheaper (and often better) alternative, but to be able to control the temperature to follow the suggested thermal profiles you are going to need a controller capable of compensating for the high thermal inertia usually related to cheap mass produced food ovens. The only high cost device to buy is a reflow oven.
Lately these costs, thanks to some Chinese production facilities and resellers (like Elecrow, SeeedStudio, ITead, etc…), have been lowered from several hundreds of dollars for a steal stencil to less than 20 USD, allowing even hobbyists to build devices with modern and difficult footprints. Reflow ovens are the first choice in the industry for production and prototyping, the only downside are their cost and the costs related to reflow technique: you are going to need a stencil for every board and you need to use solder paste which is generally quite expansive. BGA components are of course impossible to deal with and for them a reflow oven is a must.
Some footprints like QFN are very difficult to be soldered with an iron even for a trained technician and often those joints are not good enough even for prototyping purposes. It also requires some skills to be able to solder smaller components and high-density pins. While many SMD components can be soldered with just a standard iron this is generally a very slow process. Because it is easy, fast, reliable and gives professional results with very little skills to master.