Applying solder to copper tracks

The bigest problems with your green board in the opening post are the size of the pads and the solder mask partially covering the pads.
Why the solder mask covers the pad, I can’t answer, but the pads can easily be changed to something more suitable for your young newbees.

Below is a board layout demonstrating examples of various pads that are easy to create.
The Rs are 20 mm between pins, C2 & 3 1.5mm and C1 & C4 2.5mm.
Note the pads with red arrows. These have offset holes. Pad 1 C2 can be of use to increase the copper area if the wires from the cap. can’t be spread.
Note also the purple ring surrounding the pads. This is the solder mask expansion. This moves the solder mask away from the pad. This is best viewed in the 3D image below. Solder mask expansion is set at 15 mil which still leaves some mask between pads on C1 & C4, but removes mask between pads on C2 & C3.

Pad editing can be done in the Footprint Editor or directly on the PCB with Pad Properties.
Solder mask expansion is set in PCB Editor > File > Board Setup > Board Stackup > Solder mask / Paste.

I hope this belated comment is of help.


Hi jmk.

That was a fantastic reply which is so useful. Thanks very much!!! I’m now working with Kicad and getting what I want out of it thanks to such brilliant help.

Thanks again.

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Surely the readability of the RH panel has more to do with being able to see where the tracks go. If you want easier soldering for kids who don’t yet have good hand-eye coordination, you could make the pads larger, more widely separated, and retain the soldermask.

I’ve seen old single sided designs where silkscreen on the component side echos the copper on the other side.

This is where I’ve got to now. Main difference is now the pads are larger and tinned.

The teachers say they don’t want silk screen as it will then become too easy.

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Looks good. Big pads and thick tracks are a must for the inexperienced solderer. There is far less chance of lifting the copper from the PCB.

Using solder mask is also good. It requires more effort and concentration to get the soldering correct. Without soldermask, extra solder will be drawn to the copper tracks. With soldermask, not only do the students have to get the time and heat correct, but also the amount of solder.

You can tell them they are stupid teachers, and doing more in CAD to make production and assembly easier is a good thing. Or, (if you want to be a “good” student) say nothing and just act as if they are right and you understand it. (Or do something in between. I’ve never been very good at social things myself).

I did have a look at the first photograph, It has solder mask all over the pads and that is not a good thing. I am not sure what happened there, but I guess you used via’s instead of pads.

I’m not so sure.
No silk means they have to read and understand the schematic drawing if they wish to solder the components in the correct holes.
With silk means they only have to associate the Refs with the Values.

Hmmm, maybe.

But if they just created the schematic itself and created the PCB themselves too, then that is a passed milestone, and silkscreen just helps prevent making silly mistakes during soldering. Although I agree that is a step students have to learn too. Some 30 years ago I did solder a few home etched (no solder mask nor silkscreen) PCB’s by hand, and that is a good educational moment of the benefits of the Silkscreen. Making mistakes is an important part of learning, and works much better then just reading some texts.

i love the #baresolderpunk look. It reminds me of my youth covered in ferric chloride.

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With that and sodium thiosulphate, I was the bane of my mother’s life. :neutral_face:

Well I was 13 when I started soldering with tin/lead solder, and I blame the fumes for my sense of humor. :crazy_face: Maybe 11 or 12 is not much worse. But ROHS solder is more difficult to work with.