[nathan] sends in this combo of projects which combine to make a very interesting reflow oven.
First is PowerCore which has two microcontrollers, an ATmega and a ESP8366 working in tandem to turn the AC on and off at set intervals. A GLCD displays the current profiles and WiFi allows for remote control as well. Input is handled by a momentary switch rotary controller. He decided to go this route after reading forums on the commercial controllers and deciding they needed too much fiddling and weren’t hacker friendly enough.
The PowerCore then attaches to a halogen work light. He took the front glass off the halogen light and covered it in aluminum foil. This becomes the base of the oven. The PowerCore and a sensor are attached to the back. Using the lighting element as a heating one makes sense and, as we can see from the curves, appears to provide a very accurate response.
On top of all this [nathan] has documented the project beautifully. The small size and great control bump it way up in our list of reflow builds to recommend.
Ok fine, we get it that sometimes HaD does reviews on closed-source projects. This is ok and we can still learn stuff from well-analyzed closed hardware and closed software. But let us not be so crass as to not be up front that all that is being done here is an advertisement for his indiego project.
The open version:
https://www.youtube.com/watch?v=ZDQNOU2w_ek
:o)
Heat a chip for hours?! Most chip will fail long before that.
Balderdash.
Did you look at the video? Nothing there.
Hi all, thx for your comments, Nathan here. Just to clarify — this project is entirely open source (hardware, software, STLs, etc.) and everything will be released when we run the first batch of boards. I’ve just been waiting for enough interest to justify building a bunch of boards. The motivation behind waiting to release the source is to avoid the awkward scenario where clones appear before the original project launches. If someone wants to build one before I run a batch of boards, just email me!
It will help get things to a point where I can release everything faster if you can express some interest in the project here (even if you don’t want to go in on the initial boards, that’s fine): https://forms.gle/bnKJQnud6wE4r14DA
Thanks! -Nathan
I do reflow with a £20 halogen lamp. A £5 zero point crossing detector a £5 thermocouple and an arduino. It works great. I win.
I use bathroom IR heater as the base heater, halogen light with 600W short bulb as top heater, arduino with two PID loops, two thermocouples, two opamps, two triacs, zero cross detect transistor and a big 20×4 display. It has repaired many GPUs and notebooks that work to this day for years. I have never reflowed new SMD boards on it though but desoldered few motherboards, so i could say that it can do this too. to get most fun out of it make reflow party with friends, pile of GPUs and notebooks, a grill and beer. Use RMA223 flux and and HY610 heat conduncting pasete to reassemble and you’re ready to go.
Hmmmm…. Fire insurance fully paid up?
i was thinking the same: nice way to burn the floor. i get why he did it this was around but still seem like a risky thing to do. i have to admit i never have heard of reflowing with a halogen lamp before but i don’t really understand why he had to use two microcontrollers to do it.
I’m not actually convinced that board is safely laid out (enough mains isolation, etc.), especially if someone’s trying to sell that, but it’s hard to tell from the pictures.
Halogen lamps don’t work as well because most components and the board itself do not absorb visible light very evenly, so you’ll have much less even heating. This is why most reflow ovens are in IR – or my favorite trick, from mikeselectricstuff – take a normal $20 toaster oven and stick a variac on it. I think he kind of realized this, but if you run them at maybe 50% power, before the heating elements have substantial glow, most of the power is emitted in longer wavelength IR instead of visible light. That’s all you really need to reflow boards well. IIRC halogen lamps are designed to emit more visible than IR, so they’re kind of inherently a bad choice.
I’ve reflowed 0.4mm pitch BGAs with the toaster oven. Usually the limit is how accurately you can place the components by hand.
Thanks for your comment! I have carefully laid out the board to make sure everything is w/in safe tolerances and then some. To your point, the safety of the design does depend on the reliability of the AC/DC module, which has been chosen and sourced with safety and reliability top of mind. That said, working with mains is dangerous (duh), so this project is not for the inexperienced.
halogen lights do not emit more visible than IR, they are just barely above the 10% visible light vs IR of incandescence light, mainly due to higher temperature (3000/3500K instead of 2500/2700K).
This. Halogens/incandescents are IR emitters. There’s some visible light on the shoulder as the blackbody curve rolls off, though.
https://upload.wikimedia.org/wikipedia/commons/c/cc/Halogen_spectrum.svg
Some time ago we even had a commercial reflow ofen (~ €3000,-) in a small company where I used to work. This also used (long) halogen tubes as heating elements. And it worked.
I just use an unmodified convection toaster oven that I think I bought used for $10 or maybe $20. I have never had any problems with reflowing boards. I’ve probably reflowed around 100 boards or flexes in it by now. I don’t understand why people make it so complicated.
I always wonder how little information is visible on hackaday.io pages. just 4 pictures, 2 movies and three alineas covering more than a normal page, forcing me to scroll down, to nothing extra. hackaday: PLEASE upgrade this horrible interfarce. pulease!
Don`t understand this, most toaster ovens also use halogen “lamps” for heating
It’s an old idea: https://hackaday.com/2017/07/13/a-bright-idea-for-reflow-soldering/
… but a good one.
A pitty you didn’t credit previous similar works… looks like you made the project without previous research on what had be achieved before.