The thermocouple should be firmly pressed against the hot plate. The LCD can then be screwed in place, together with the button. you have laying around can be made to fit. Some additional holes need to be drilled: one for the power cord, one for the button and two for the LCD. Add the hot plate and secure it in place (mine is secured with screws in the bottom). The pieces can be glued together as a puzzle, just use enough clamps. Due to the living hinge, this design can only be made on a lasercutter: small slits in the MDF make it able to bend. In my case however, there was not enough room, so I had to design a new one. A first option is to modify the existing enclosure, this is viable if it is big enough to accommodate a SSR, LCD etc. But, for most hobbyist use, it's overkill.For the case we have two options, depending on your hotplate. It is more precise, which is important if you have more sensitive components. Last year I built a temp-controlled reflow oven using the Controleo3. Unless you have especially sensitive components (like WS2812 LEDs, which I have found best to hand-solder), this works really well, is cheap, and easy. I used the following "profile", turning on a stopwatch when I turned on the oven: I used a thermocouple the first few times I did this, and you may want to do that to get a feel for it, but mostly found it unnecessary. I switched to an unmodified, cheap toaster oven, which I have used to do many boards. This was OK, but I found it a little touchy, and tended to burn the PCB. Stencils are quite cheap now, I see no reason to manually dispense paste from a syringe, which I find pretty finicky.įor the actual reflowing, I started with a hotplate. Any more than that, and I will get a stencil and reflow. 0603 passives and SOT-23 or SOIC-8 size), I will hand solder them with an iron. For me, if there are only a few SMD components on a board, and they're not too fine pitch (e.g. People vary in which type of assembly they prefer. I do a mix of one-offs and 10s of boards, with anywhere from a few to hundreds of components. I have done a lot of at-home assembly of SMD boards. For example, I would not use hot air to reflow a large 10" wide PCB with many surface mount components and plastic connectors, but I have done 1" PCB modules with hot air and found that it worked fairly well because the boards were so small I could evenly heat them. Further problems occur with plastic components, which tend to be hard to reflow without melting because you don't have that fine control over temperature. The disadvantage is that it is hard to reflow large boards evenly, so except for very small PCBs you will probably end up applying too much heat to some areas and too little to others. The advantage of hand reflow with hot air is that it is fast, doesn't require a reflow oven, and for prototyping can work quite well. The disadvantage is usually cost, and that cheap reflow oven often do not precisely track the programmed profile. Assuming the oven is well calibrated you can precisely reproduce the manufacturers reflow profile, hopefully resulting in reliable soldering and very low probability of damage to components. The advantage of a reflow oven is that it evenly heats everything in a controlled and automated way.
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