Hi all, new to the forums; not sure if this is appropriate here or in 3D Printing: I have smallish electronics boards I’d like to custom mount on/in a 3D printed box or chassis. These (an LM2596 DC/DC converter and an ESP32 devkit board) have mounting holes, but there are traces or components near them with essentially no clearance for a bolt head. Yes, I could solder the ESP32 to a custom circuit board with better mounting access, but there’s really no opportunity for that on the DC converter. Are there good solutions out there?
You could 3d print an enclosure with slotted grooves but mind that the LM2596 is soldered on a large copper plane, with many vias to the other side, to dissipate heat. When it fits too snugly in its enclosure it might overheat.
The ESP32 does not pull very much power through the LM2596.
you could design a box with 2 covers and a center section with pinches the ESP at the mounting holes(which are sitting on pins of the bottom cover). The other side of the center section could have a shelf for the buck converter with 2 mount holes then the top cover has pins which interface and pinch the buck converter in place.
Or just make a larger box and stuff some foam between the boards and tighten the cover.
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I have used exactly the same buck converters to supply 12V to some self adhesive led strips. Although these boards are rated for 3A, at 0.75A the temperature rises significantly. That might be less of a problem because the ESP board consumes less power but when the heat accumulates in a tight space it is something to be careful with.
Another issue I had with one of these boards is the potentiometer. After a few months I noticed that the light intensity changed. That was not a problem for a led strip but in case of a microcontroller you don’t want that. I suggest you replace the potentiometer with two fixed resistors once you have the correct setting for the required voltage.
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I’ll be driving servos (or possibly stepper motors) through it as well.
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I might be able to use the pin solution with the ESP chip; there’s a little space around the mounting holes to engage with if I can print the pins with enough precision.
The buck converter is just impossible, though. I think what I’ll end up doing is gluing it to a (probably printed) carrier plate with usable mounting holes. And the more I think about it, I may as well do that with the ESP, too. They’re both pretty cheap, so making a permanent attachment isn’t really that big of a deal.
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There’s not even enough clearance along the sides of the LM2596 board to fit in slots. Per my other comment, I’m just going to glue them to carriers.
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the cool thing about plastic pins through mounting holes is that you can just do a little top melt and the board stays in place.
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Doh! I never thought of that.
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If it’s always upright, sure. I have an application in mind that’ll be handheld. Someone’s suggestion of foam under a top panel would work, of course.
Many of these boards use the backplane as a heatsink, if you mount them with foam etc. be careful not to block airflow underneath any bits of the board used for this.
This is the back of a similar board. The ‘pincushion’ of through-plated holes conducts heat from the chip mounted on the other side of the board into the large copper area around it. If you are running high power through the converter make sure you allow air to flow here.
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