Help with SMD soldering 240203

Hello @benmorius, @mathewbusby, @malcolmputer,
@tmc4242, @barkingchicken, @artg_dms and the
DMS Electronics forum,

Working on project shown at

which uses SMD components.

Have done thru hole soldering for
over eight years on dozens of projects
with good result.

Have been working on the Neopixel PCB for
several days with no luck.

Have viewed several videos including
the one in the post in this forum


All of the videos seen, like the one above,have
component elements that extend out away from the
component body. In the Neopixel project
the WS2812b LED chips the pads on the chips
do not extend out from the chip.

Willing to pay $50 to anyone who can
show me how to solder these chips.


Allen Pitts
[email protected]

Have you tried using hot air? If the PCB land pattern does not extend much past the component pad, then soldering with an iron can be difficult. I’d recommend tinning the pads with an iron or using solder paste and reflowing using hot air with a generous amount of tacky flux.

I have rig that i have to fix. I could do it at makerspace when do you need it done?

I also have the j std 001

DIDODI Soldering Practice Kit…

The WS2812 packages have a history of failures when soldered using reflow. The problem appears to be much worse when hand soldering - as in you are luck to have a functional part when hand soldering.

I’ve avoided them as components if I had a choice because of their reputation and their funky timing requirements. I have several commercial strips, end even there their failure rate is unpleasant.

So you are suggesting a common cathode through hole? the color still have to be curren controlled (i.e. pulsing via a pwm or rheostat).

Yup, heard of them, but the OP was asking about hand soldering SMD neopixels which are WS2812B RGB LEDs with an integral driver. The packages are finicky and hard to solder using reflow, and generally much worse by hand. This is not a good choice for newbie SMD hand soldering.

If you want to assemble these yourself, they really need to be reflowed in our IR reflow oven, and even then plan for problems.

Hello ceramicCap and the DMS Electronics forum,

Have Bible study on Tuesday morning between 7 and 8:AM and a bluegrass jam Thurs at 11 AM. Other than that any time, any place.
Will bring PCBs, components, solder paste, solder, flux and tools that are being used.
Allen Pitts
[email protected]

The reflow oven on the top shelf may need repair. I didn’t see a users manual. I could not make it work. Lights light but buttons don’t button. I am very interested in reflow work as well, also using WS2812B’s in the 5050 form factor. I bought a reel (1000) of WS2812C-2020 for a high density project, so reflow is the only option.

I’m not shocked. I’ll try and look at it during office hours Thursday if some spare time presents itself.

Hello James_Brand and the 3D Fab lab forum,

Success has been found using solder paste:
Chip Quik SMDLTLFP Solder Paste Sn42/Bi57.6/Ag0.4 No-Clean Lead-Free Low Temperature Melts 138C 281F

The issue was first thought that that too much solder paste was placed on the SMD pads.
But even with a tiny amount of solder paste place on the pads
the solder paste tended to pool and bridge which was thought
to be a fatal error.
The real key was discovered that not enough time was spent heating
the paste. When it was realized, from the excellent
help of Tom (Tom, what is your last name if you read this?)
that if the solder paste is heated long enough (eight to ten seconds
at about 400 degrees Farehnheit)
two things happen: 1. The solder paste gathers onto
the pad. 2. The components, the WS2812b pixel
and the even smaller 0.1 uF capacitors (0603), will sort of
wiggle themselves into place.

It was not possible to discover the method from YouTube tutorials
or forum posts. The discovery of the the process was
only edified by hands on demonstration.

Following the very incomplete Instructable at

the home made pixel ring was finally complete. This is a
a video of my final product:

And so after a dozen or so YouTube tutorials
and a several days of frustration
the method for soldering SMD components
was found through the kindness of a stranger,
Tom, who demonstrated the use of a hot air
gun for soldering SMD components.

If there is some one who is still doing
through-hole soldering and would like to move
on to SMD components, respond to this
post. You will find that, like Tom,
I am

Privileged to be,
Your humble servant,

Allen Pitts

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