Suggestion on how to solder this LED - Page 1
Forum section: electronics / projects

author: madworm
author_rank: Frequent Contributor
timestamp: November 02, 2012, 12:55:23 am
content: Currently still I'm planning to use paste + soldering iron, but I have my doubts.Would going for baking / hot-plate / hot-air right away be the better approach? I'd have to get the tools for that.The number of boards is < 10.

author: Psi
author_rank: Super Contributor
timestamp: November 02, 2012, 01:20:19 am
content: Can you post a pic of the actual LED?It should be fine to do with just an iron though.The easiest way to solder most 2 pad components is to tin one pad then use tweezers to place it while heating that pad.That will hold it on while you solder the other pad, then you can return to the first one and touch it up if needed.Remember to give it a little time to cool down before moving between sides or the heat may transfer through and melt the other side.If you tin both pads you will find it really hard to get the component flat.

author: IanB
author_rank: Super Contributor
timestamp: November 02, 2012, 01:37:05 am
content: See tutorials here for illustration of general technique:

author: sacherjj
author_rank: Frequent Contributor
timestamp: November 02, 2012, 03:24:53 am
content: I find paste and a hot air iron really easy for stuff like that and the result is good. But you should be able to do it with an iron and good tweezers. You can tin one pad. Use tweezers to set flat on board with iron on tinned pad. Then solder the other side with a bump of solder.Hot air will self center, like normal reflow. I think the cheap Atten unit off ebay has been really worth it.

author: madworm
author_rank: Frequent Contributor
timestamp: November 02, 2012, 11:30:48 am
content: @IanB: I know how to solder with an iron ;-) I just don't want to waste my time if it can be done quicker.I guess I will have to see if I go mad after the 3rd or 4th board... and switch to one of the other methods.

author: jeroen74
author_rank: Frequent Contributor
timestamp: November 02, 2012, 11:40:57 am
content: How many LEDs in total do you have to solder? If it's only 10, surely hand soldering is faster any time. How long does it take to get other tools?I actually solder two pin parts with two soldering irons simultaneously. Tin both pads, place component and tack on one side, apply flux then apply heat on both sides. Part aligns perfectly automagically and no need to place components accurately which I find the most tiresome part. But this technique only seems to work properly when the board is preheated to ~100C, but that could be because I only tried it on a 6 layer board so far with two solid inner ground planes.

author: andyturk
author_rank: Frequent Contributor
timestamp: November 02, 2012, 02:59:51 pm
content: I tried the "wet tack" method, but my caffeinated hands make it difficult to transfer solder from the iron to the first pad with 0603 parts. I've been more successful with solder paste.1) dab a tiny bit of solder paste down on the first pad only2) position the part and hold it with tweezers to prevent tombstoning3) touch the iron to the pad with paste4) solder the other pad normally using an iron and fine rosin core solder

author: ee851
author_rank: Regular Contributor
timestamp: November 02, 2012, 03:28:24 pm
content: Thank you for posting the videos. Watching them has encouraged me to have another go at working with surface mount devices.