Pad Properties, what impact dose the Technical layers options have?

Hello just wondering if someone could explain what the Technical layers options in Pad Properties tab do?

Just trying to make a NPTH as I’m planning on having these done on a single layer PCB, so don’t want plated through holes in the gerber.

Notice in 3D view if I untick the F.Mask and B.Mask the holes are there, but with a mask over them. and when I have them ticked I see what looks like a small amount of solder mask clearance is added to drill hove, even though my value for clearance set to 0.

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I think you already found out what they do: they add the pad shape to the said layer. You can control the clearance for paste and mask separately in the Local Clearance tab. The clearance is needed for the mask because there should be room for the registration error for the whole mask layer (the minimal clearance recommended by the manufacturer). But see How does solder mask layer work? and the recommendation to find out what your manufacturer wants. It’s possible that they add the mask hole themselves if you don’t.

If it’s not clear already: because the mask in the manufactured board is substance applied to the board after it has been drilled, there should be hole in the mask (graphics in the mask layer) so that the mask isn’t poured into the hole.

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Thank you, that was very helpful. But, I don’t quite understand the part:

A neat trick is to draw a zone (not just a graphic polygon) around the whole board and set the width to 0. When you fill zones, this will be filled, too, so that it covers the whole board area but nothing more, just like with copper zones.

As I’m sure you can tell, I’m very new to KiCad.

I just left the top solder mask layer out of my Gerbers as I only wanted the bottom to have a mask (and left them a note).

How are you having your PCB’s manufactured?
These days it’s rare to have separate prices or process for single layer PCB’s, and if you order a single layer PCB, the most likely thing to happen is that they make a dual layer PCB, but etch away one layer completely.

For example these remarks on single sided PCB’s:

It also states you can not simply delete a solder mask layer from your gerber files set. (They call it a “stop mask”), as it generally is a “negative” layer, and absence of the layer is apparently interpreted as “cover everything”.

How are you having your PCB’s manufactured?

I Will be using JLCPCB for the prototypes and then projects that go ahead will be made here in the UK in larger volume, mainly due to the substrate I use.

I only really do reproductions of vintage PCBs for repair and retrofitting at the moment, like this:

Seen there is no real difference in price for single over dual-layer, but right now my PCBs are all just single-sided, no mask, no silkscreen, with just an OSP finish. So having all the extras even though they don’t cost any extra just seems a bit wasteful to me.

But that said am planning to move into doing more modern PCBs taking advantage of the mod cons, so just playing with KiCad and trying to get used to it and a potential “normal” workflow over my current very long-winded and expensive process that means more work for me, and higher prices for customers, so trying to bring both of those factors down.

(also first time using one of these prototyping services, with the exception of some OshPark PCBs for personal projects about 10? years ago, im more of a point to point, turret board kind of guy, Vero stripboard at a push and feeling fancy :smile:)

Showing a picture of the sort of PCB’s you want to make clarifies a lot.

Are you satisfied with a functional reproduction, or do you want accurate copies, including the curved hand-laid tape look?

The current stable version of KiCad (V5.1.10) only does straight copper track segments. KiCad-nightly V5.99 does have some support for curved tracks but it’s still in an early stage of development.

There are some 60+ “side projects” around KiCad and one of them that may be of interest to you is:

I have actually been using the svg2shenzhen plugin this week as for me (well my customers) the aesthetics are everything from the hand taped traces to the old phenolic look. svg2shenzhen has a few quirks, main two bugbears for me are:

  • No current implementation of NPTH, a problem for single-sided boards.

  • Bring all my holes in under sizes by -0.0001mm, so a 1mm hole come into KiCad as 0.9999mm

Not sure how problematic the latter of the two really is for fabrication, but iv been left click, pressing E, and changing a LOT of holes these last few days to resize them and make NPTH to make them as fab friendly as possible and I guess it’s responsible for me now trying to learn KiCad and I can get curves onto the copper layers with it, so I has really been useful for my use case, and just finished the obligatory Getting To Blinky v5 training videos, so hope to be playing with more conventional layouts.

(and to be frank, having traced a few vintage PCBs in Eagle with curved traces, even that is more work svg2shenzhen+KiCad, just hope svg2shenzhen keep up with the newer versions of KiCad as it seems somewhat abandoned at the moment with the last update being over a year ago, shame as it is ideal for my needs!)

Ah, yes, I did remember a recent thread about that plugin, but only just now saw it was also started by you (and it describes the sort of projects you do, which also rang a bell, even though it was not very loud).

Our local PCB factory while doing prototypes they put at one form (size right for their technology) many projects and manufacture them together. They can’t skip the top-solder mask placing at pcb just because you didn’t send them that gerber. Don’t know how other factories do prototypes but it seems being logical to made many at once.
If you don’t want top-solder mask the right gerber telling no top-mask would be better then no gerber at all, I think.
I know nothing about JLCPCB but you probably can find the information about their prototype offer - if it is by definition 2 layer or may be they also offer single layer prototypes. As a global firm they can get so many single layer prototypes that may be they have special process for it. Who knows.

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