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Tiny SMD Resistor Soldering

A project log for My Advanced Realistic Humanoid Robots Project

Building bio inspired realistic looking humanoid robots to do chores and sports and stuff.

larryLarry • 10/21/2025 at 15:16•0 Comments

Well I finally got back to the electronics after about a month long detour real life interruption. All kinds of stuff slowed my progress on this session. But I got stuff done nonetheless. 0603 LED to 0805 resistor and some nickel strip leads coming off. Tested and working. This will be the indicator light for when the lowside mosfet comes on for one section of the custom BLDC motor controller. 0603 LEDs are extremely tiny for hand soldering and they don't take solder well either. I was originally going to go with blue LEDs but chatgpt said that would give off a unrealistic color through the silicone skin so orange would be better to give a more natural and less silicone skin piercing indicator light. Somehow I ran out of 470ohm resistors so I had to order more and I used my 200ohm ones instead for now. Which are a bit too bright. But chatgpt said I can diffuse the LED with a glob of silicone tinted black to darken and diffuse the light it gives off which sounds like a good idea to me. I am planning to use wire wrapping wire to come off of this assembly and tie into things. Somehow just attaching these two parts and testing it took me almost 3 hours. Between studying the schematic to refresh my memory on what is going on, visualizing placement options, overheating and destroying one LED, trying to locate the right color LEDs, shopping for replacement 470ohm resistors, researching and substituting in 200ohm resistors, discussing LED color options with chatgpt, figuring out how to solder a 0603 LED directly to a 0805 resistor part to part by hand, accidentally breaking a part off of its nickel strip lead and having to redo the connection, etc etc. All of it just crawls. Hard to stay patient with electronics sometimes and I do things in inefficient ways often. Learning what can and aught not to be done is tough from a patience perspective. But I insist on trial and error and experimentation which takes time. I just need to get into a daily habit to stick with it till completion. It's all complicated. Trying to figure out how to electronically isolate it all next. Thinking of using lamination plastic taped around it all so I can still see it all and visually troubleshoot. Also I'm considering how I can use solder wick braid as a heat pipe for each mosfet and run that over to the liquid cooling system. But it can't conduct. So thermally it can conduct but electrically it can't. Trying to figure out whether to create a barrier of micah or just thermal silicone for this and the routing needed. Also considering if I need mini coaxial shielded cable for the wiring of each or just regular wire wrapping wire when going from microcontroller to mosfets etc. Also trying to figure out if I need hall effect sensors or back emf reading or no feedback but my potentiometer and the implications of each option. Just so much to consider in all of this. And all of those considerations also slow things down even more as I have to make decisions on it all. It's quite overwhelming.

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