From: Clint Jay <cjaysharp@gmail.com>
To: Microcontroller discussion list - Public. <piclist@mit.edu>
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Date: Wed, 3 Feb 2021 10:09:05 -0800
Subject: Re: [EE] Measuring PCB copper weight?
Thread-Topic: [EE] Measuring PCB copper weight?
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I'd perhaps ignore the soldermask and measure bare substrate then copper
and subtract the difference working on the assumption that soldermask
should be fairly consistent. If that gives wildly varying results then
scrape away.

On Wed, 3 Feb 2021, 17:59 Neil, <picdude3@narwani.org> wrote:

> I have calipers w/0.01" resolution here, but not sure if that will be
> accurate enough, especially with soldermask, which I'll have to scrape
> off.  I can't measure pads as that will have a plating on it.
> Google tells me that 1-oz is 1.4 mils thick, so I guess I could run out
> and get a better caliper or micrometer for this.  Even harbor freight
> calipers should be good enough for this I guess.
>
>
>
> On 2/3/2021 11:54 AM, Clint Jay wrote:
> > Micrometer? The thickness of the copper should be a giveaway
> >
> > On Wed, 3 Feb 2021, 16:01 Neil, <picdude3@narwani.org> wrote:
> >
> >> Is there a simplish way to figure out or measure the copper weight on =
an
> >> existing PCB?
> >>
> >> I'm asking because I'm redoing a layout for someone and I did not do t=
he
> >> original circuit design, so was planning to use the same trace widths =
as
> >> on the original board, but I'll need to know the copper weight to orde=
r
> >> a prototype board.
> >> If I have to redo the math on current etc, that opens up another can o=
f
> >> worms as I don't have all of the specs otherwise.
> >> And the copper does feel thicker than usual.
> >>
> >> Thanks.
> >>
> >>
> >>
> >>
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