Soldering on Saturday Night!  I'm curious if anyone has had success soldering strips of

Archive FastLED Archive
1

Soldering on Saturday Night! I’m curious if anyone has had success soldering strips of 144/m APA102 or other 4-wire strips butting together. I have soldered sporadically for decades, but I can’t seem to get the soldering iron in close enough without melting the 5050 LED casings and generally producing connections that I don’t trust at all, if they connect at all.

I’m about to give up and just wire the splices with wires going into the back of the strip instead of using solder to hold the butted strips, but thought I’d ask if there was any secret I’m missing. I have a ~2mm diameter cylindrical tip with chisel end on my Weller WESD51 temp controlled iron.

An adafruit tutorial https://learn.adafruit.com/1500-neopixel-led-curtain-with-raspberry-pi-fadecandy/preparing-led-strips made me think this would be possible, but I neglected to notice that they were working on 60/m which have a lot more space to maneuver the soldering iron.

2

Okay, answering my own question, I’m having much better luck soldering the butts on the backside than the front side. I’m thinking this might do it…

3

Thanks for the info. I may need to try this myself. Are you tinning the pads at all first before heating on back?

4

Using rosin?

5

I spent a fair chunk of today working on exactly this. My solution was to use some very thin wire to sew the pads together before soldering.

I took plenty of pics, so I’ll see if I can get a detailed blog post up about this approach tonight.

6

I actually went as far as to grind the tip of my old soldering iron down as to make it longer and sharper…worked a treat

7

Just make sure you don’t grind a brand new tip as you’ll remove the plating and your tip will oxidize much faster…

8

Thanks Jez I commented on your post with more info on how I did it similarly to you. Thanks all for your help. BTW didn’t have to pre-tin or use rosin with the approach referenced in Jez’s post.

9

I’ve only worked with 60/m so far, but I always use a wee bit of flux on the pads and then tin them. Then I tin the end of a piece wire far longer than I need. I bend the tinned end so that the bent portion is the length I need to join the pads. I also tape down the two strips I’m joining and, if spacing is critical, I line them up with another strip running parallel to them (so I can line up the LEDs). Then all I have to do is hold the short tinned portion of the bent wire on top of the tinned pads and give it a quick touch with the soldering iron. Then I use my nippers to trim the extra wire off.