Share tips you have come across

@larryd I love your post #692. Brilliant! And when I saw your photo of the capacitor going to the ground plane I thought this would be a great EMI barrier for projects in an noisy environment. One could drill a hole in the center of the isolated pad, bring a wire through and bypass it with a cap.

I am not a super fan of using ‘hollow desoldering needles’, but they have their place.

You do have to be careful not to damage the plated through hole when using these.

A set of needles can be found on eBay at reasonable prices.

However, I find an assortment of stainless steel ‘Blunt Dispensing Needles” are reasonably priced, come in a variety of diameters, are easy to manipulate and they do a good job.

Of course, the solder wick 'with' solder flux technique is also useful but your pads can be lifted if you are not careful.

An SC-7000 desoldering gun is always nice to have, but it is expensive.

@JohnRob
The technique is useful for prototyping circuits.

As mentioned previousely in the thread, you can also punch out copper pads form 1/32" PCB material to do something similar (or even combine the two methods together :wink: ).


Mounting switches and other electronic components in a wooden box can sometimes be difficult.

The length of the switch, and the wall thickness of the box may be such that you cannot add mounting hardware to secure your component.

This discussion shows one method to make mounting such components easy.

Equipment needed:

  • Forstner bit
  • Brad point bit (component mounting bit)
  • Drill press
  • Good quality wrench

Forstner bits come in many diameters:

2019-12-25_16-37-09.jpg

That is often my approach but clearly much better documented.

Thanks as always Larry for these tips.

I used a Chinese acrylic glass laser cutting service for the first time and I am quite happy with the result (cover plates for wall thermostat project).

I had quite complicated ideas in mind about 3d printing covers, but I think this is much better than anything I could have printed.


How about a link to where you got this done.

larryd:
How about a link to where you got this done.

Wasn't sure if that was seen as advertisement. I had this done at Elecrow. They also do PCBs that I am quite happy with and seem to arrive a little earlier in Germany than Seeedstudio.

LED ‘Breadboard Helper’.

You can make an 8 LED board to speed up prototyping on your solderless breadboard.

Discussed below, is an 8 coloured LED board and a series resistor board.

Images show a ‘Common Cathode’ circuit, ‘HIGH’ on Arduino outputs will turn on these LEDs.

If single colour LEDs are used, you can rotate the LED board 180° and move the resistor common to +5V for ‘Common Anode’.

50Pcs SMD To DIP PCB Pinboard 0805 0603 0402 LED SMT 20.3*10mm Board (50 for ~$4.00)

https://www.ebay.ca/itm/50Pcs-SMD-To-DIP-PCB-Pinboard-0805-0603-0402-LED-SMT-20-3-10mm-Board/312911841778

Even though these adapter boards do not say 1206, you can solder 1206 LEDs on them (magnification helps :wink: )

LED     Resistor
White   4700Ω
Red     2200Ω
Green   1200Ω
Blue    4700Ω
Yellow  2200Ω

larryd:
LED 'Breadboard Helper'.

You can make an 8 LED board to speed up prototyping on your solderless breadboard.

You can buy a readymade 6 LED board.
https://www.aliexpress.com/item/32273206116.html?spm=a2g0o.productlist.0.0.5b9250c8nGrFw9&algo_pvid=69f491ff-d8a0-4552-9cd5-55f21bc32e46&algo_expid=69f491ff-d8a0-4552-9cd5-55f21bc32e46-49&btsid=faf74563-88a2-4efd-aae1-6a27e360a30d&ws_ab_test=searchweb0_0,searchweb201602_6,searchweb201603_53
Only single colour LEDs and not as versatile as your design, though.

I prefer my version:


Closeup of the modules.

Resistors are on bottom (SMD), can be made common anode or common cathode. Quick for checking Arduino's output. I had a few old 20 LED bargraph but also fits 2x 10 LED bargraph. Headers are all on one side so I can just mount them on the side of the breadboard.

If you purchase a board like a Buck Converter ‘and’ the board doesn’t have components on one side, you can use it as a Castellated daughter card on a PCB you design.

Use a table sander to take off the edge(s) of the PCB where the through solder holes are located.

For insulation/isolation purposes, place Kapton tape on the flat underside of this PCB.

When 1/2 of the buck converter hole is removed, solder the remaining plated through hole to the motherboard’s pads.

On a none castellated edge, tack the daughterboard to the motherboard, use UV glue.

You can use ‘Solder Wick’ to manually generate a small-scale solder wave.

PCB factories use a solder wave method to solder plated-through hole PCBs.

B.png

C.jpg

This can be accomplished on a much smaller scale with a ‘Gull Wing’ soldering iron tip.

Continued in the next post . . .

A.png

B.png

C.jpg

A.jpg

We have all used solder wick to remove excess solder from electronic component leads.

By reversing the process, you can use solder wick to apply a controlled amount of solder to small fine pitch components.

Use a magnetic hold down tool to anchor your component to the PCB.

Add a drop of liquid flux to the leads.

Melt a ‘small’ blob of solder on the end of a piece of solder wick; small being the operative word.

Add a drop of liquid flux to the blob, heat with a soldering iron.

When the blob melts, slowly drag/pull the solder wick blob over the component leads; the leads take only the amount of solder they need.

Add more solder to the end of the solder wick as needed.

Experiment with different widths of solder wick to see what works best for you; 2mm wide wick is used in these images.

Going to refer to this from now on as the: SW2 soldering technique (SolderWick/SolderWave). :slight_smile:


Melt the blob, pull the wick over the leads.

There are two kinds of 90’ male headers available.

I prefer the the header in the 1st image as it has a lower profile.

bB.png

Further to posts #713 & #714

Another example:

Hi Larry, IPA := Isopropyl Alcohol ?? Like to be SURE with chemicals... THANKS!

Hi Terry, hope the family is well, better stay out of China for a while :(.


Yes IPA is Isopropyl Alcohol (99% from Costco)

Use an old electric toothbrush with the IPA to get in between component leads.

Rinse with water.

Use ’hot air handheld soldering wand‘ to dry PCB (or your wife’s hair dryer :wink: ).

00159E19-5658-4337-BCF2-D09422FAD0C8.png

Always use a good magnifier to inspect for solder bridges.

00159E19-5658-4337-BCF2-D09422FAD0C8.png

hope the family is well, better stay out of China for a while :(.

Worried about our good friend/partner Jun Peng and his wife and children. They traveled back 'home' to Hunan province and are with their parents / grandparents. He said "Yes I am in PingJiang where is safe though isolated now, many roads are blocked, most of the people stay home."

The mix of Technology, Ideas and People I love seems to encompass a smaller and smaller World. We're in this together, now. I have stayed at his grandparents farmhouse several times in the past 10 years. It looks like this:

Mary Alice is showing kids this for Chinese New Year in her library in Vermont: (CLICK)