VCM II PCB Colour – How much do you know?

I just wanted to comment on the issue of the PCB plating as I am qualified (electronics and computing).

The boards are made of copper laminated to fiberglass. When these boards are made – BEFORE installing the electronic components – they normally plate the copper with tin or a cadmium alloy to prevent corrosion of the copper.

The colours you see are a consequence of the plating process.

– Tin is a silver colour and has been incorrectly described early in this thread as Aluminium which is never used for a PCB plating. Tin is the normal plating used as the solder is an alloy of >90% tin. The old 60% lead and 40% tin solder is no longer used as the lead is a poison that leaches into the ground when electronics are disposed of.

– Gold colour is the cadmium alloy plating and is usually selectively applied where exposure to moisture occurs such as connector contacts and test points. I rarely see it soley used on the whole PCB as a plating but it can be cheaper to plate the whole board rather than selectively at times.

– The real Copper colour of a red gold is an unplated board – VERY BAD. I would avoid such a unit at all costs because if they are such cheapskates and cost cutters not to have the PCB tin plated then they will have cut costs elsewhere.

There was a reply that tried to correct this matter but I hope this makes things a lot easier to understand.

BTW, There are many other issues that affect the quality of performance of any electronics such as capacitor quality.

If the board is showing all the copper tracks then that is a problem in itself which leads to oxidisation in air, most boards have a coating (conformal) to prevent this, finding a pcb manufacturer who plates every single track is impossible, coating the pcb with a protective layer of conformal prevents oxidisation in air and compared to the cost of tin varnish is minimal and the process much cheaper, tin needs high temperature to flow while varnish can be sprayed on at room temperature.

This is good info to know…

But actually…. I still think the problem we all face when we try to do certain functions is due to poor quality components (or missing components)

My vcm2 sp177-c1 works perfectly on ALL new generation ford / Mazda but have difficulty to achieve some functionality on old ford based ECU (also on Mazda equipped with ford ECU).

I’m pretty sure that the Chinese “engineers” who developed those clones didn’t copy the OEM board 100% . They must have took some shortcuts to save $$.

Big thanks to dstirrup and MrPhil who share good info with us


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