Advances in technology continue to shrink the size of components. Hobbyists, who have traditionally worked with through-hole parts, are finding these parts harder and harder to come by as more parts become unavailable in through-hole variants.
Soldering surface mount components with a soldering iron, while possible, can be a rather tedious task. In particular, when you’re working with densely packed pins like those of a microcontroller, hand soldering a board quickly becomes a daunting task.
Reflow soldering is an easier way of soldering these surface mount parts. Solder paste is applied to the PCB where the component pads will make contact. The components are then placed in the solder paste. Because of the viscosity of the paste, these components stick. When placed in the oven and heated, the solder paste melts, binding the component to the pad and aligning the part with the pads.
The reflow process itself requires that the oven be heated to a soak temperature, allowed to soak for a minute or so, and then brought up to the peak temperature for a moment before being allowed to cool. While you can do this manually in a toaster oven, the process is prone to error. Commercial solutions are expensive and provide little over a standard toaster oven.
Reflowster to the rescue!
Enter Reflowster, a simple reflow controller to make soldering with a standard toaster oven easy and painless. Reflowster simply plugs in between your toaster oven and your power outlet. A thermocouple (included with Reflowster) plugs into Reflowster and is placed inside the toaster oven to measure the temperature. The final step of set up is to put the toaster oven into "always on" mode which is typically available by turning the timer backwards a few degrees.
Reflowster's encoder and LED display allow you to navigate menus and use either a standard soldering profile or your own custom profile. Once the reflow process is started, Reflowster turns the power to the toaster oven on until a soak temperature is reached. Reflowster waits for the configured soak duration and then turns the oven back on until the peak temperature is reached.
- Pre-programmed with lead and lead-free soldering profiles
- Supports custom soldering profiles
- Doesn't require modifying your toaster, simply plug and play
- Stand-alone operation, doesn't require a PC
- Fully Arduino-compatible, upload custom code using the Arduino IDE
- Micro USB port allows for two way communication with Reflowster
- Reflowster sends serial temperature data and status over Micro USB
- Accepts commands via Micro USB when a PC is connected
What kind of toaster oven is required?
Reflowster does need to be paired with a toaster oven to work, but unlike many DIY solutions Reflowster requires NO toaster modification. No need to cut cables or risk electrocution!
Reflowster may not work perfectly with every toaster oven, but we've found that smaller, cheaper ovens typically work great because they allow for faster changes in temperature. Most simple toaster ovens without digital controls will work. In particular, a toaster that can be stuck in the "on" position is required. This state needs to persist through a power cycle. Most toasters do this by turning the timer knob backwards.
We probably don't need to tell you that you should really buy a toaster oven specifically for use with solder, since you don't want to contaminate your food with lead and other metals/chemicals.
The toaster oven that we are using is pretty much the cheapest one we could order on Amazon: Proctor Silex 31111 (http://www.amazon.com/gp/product/B004O0ANH2)
Because Reflowster is fully compatible with the Arduino IDE, new code can easily be uploaded to re-purpose Reflowster to do anything you can think of. The thermocouple, relay, LED display, and encoder make Reflowster a perfect platform for a variety of alternative projects. We only provide the firmware for performing a reflow soldering job, but with a little imagination and some programming, a variety of projects are possible. Here are some ideas:
- A temperature controlled fan
- A circadian light timer
- An outlet with an automatic shutoff
- An easy bake oven
- An incubator
- A sous-vide machine
While having a Reflowster in hand has you well on your way to performing your own complete reflow of your custom PCBs, we've added a few backing levels to help you get started right away.
If you have never done any reflow soldering yet and are looking for a kit that contains everything you need, we highly recommend backing at the "Hacker's Kit" level or above.
If you've already have solder paste, soldering tools, and a toaster (or plan on getting these) the Reflowster itself will be sufficient.
Progress so far
Over the past 4 months, we've designed the PCBs and enclosure for the first version of Reflowster and today we have the fully functional result of this design.
With the functional prototype in our hands, we were able to make a number of small, one-off improvements to Reflowster and have compounded those into a mostly-complete design for the next version of Reflowster.
The plastic case you see in these photos is a little rough around the edges because we cut holes in it manually, but rest assured that the final case will be cleanly machined by our enclosure supplier. The setup for this machining is very pricey for small quantities, so a part of your contribution will go towards a large batch of these custom cases.
Our plan going forward is to finalize another version of the board, get it certified, manufactured, and to your mailbox. We need your support to get the final few pieces of polish in place. Once backed, we can start the steps to take this prototype into production.
We all know that plans don't always work out perfectly, so we've built some extra time into our schedule. The above schedule is designed around the worst case scenario. Once we kick off, we'll issue frequent updates to let you know where we stand.
Julian (on the left) has a Degree in Computer Science and has been programming for 17 years, 5 of which have been in the industry. He specializes in designing and building robust APIs and sleek and intuitive user interfaces. He's been heavily involved in the hardware and PCB design scene for the last 2 years as a hobbyist.
Tony (on the right) has a degree in Electrical Engineering and a professional background in research and defense technologies. His expertise includes circuit level design and high voltage systems. He's been letting the smoke out of ICs at home for over 10 years, so his real world experience will be invaluable.
Check out our bio for more information!
Risks and challenges
As with many Kickstarters, if we get funded, we face the risk of over-backing. We're well equipped to produce up to 300 units. However, if we get backed above that level, we might experience delays.
Another risk lies in the FCC certification process. This is a new thing for us, and while we hope that it will go without hitch, it is possible that we'll need to redesign the PCB or implement some other workaround.
The most unique component in our product is probably the case itself. In the unlikely event that our supplier falls through somehow, we will need to redesign the case and perhaps the PCBs inside. This could add perhaps two months to the project, but wouldn't be a showstopper.
If something terribly catastrophic and unpredictable happens like our lab gets obliterated by a meteorite, we'll deliver whatever we have ready and release all our technical data and designs so that the community can finish the project.Learn about accountability on Kickstarter
- (28 days)