In our schematic entry software, PADS_LOGIC, we assign an attribute to
every part on a schematic, namely our 7-digit stock number, and the
program generates a BOM in our preferred format. That's cool.

But every board has parts that are not usually on the schematic:
screws, nuts, lockwashers, spacers, brackets, stickers, tie-wraps,
glue, heat sinks, light pipes, and of course the PCB itself.

I was thinking of creating two new logic parts

PCB the board. Ref desig PCB1

M any mechanical part that wouldn't normally appear on the sch
ref desigs M1, M2, etc

which would just look like little boxes on the schematic and have no
PCB decal. Each would get the right stock number attribute.

On the last page of every schematic we'd put the PCB mounting holes,
fiducials, the PCB itself, and as many M's as we need. Good place to
plop any useful notes too.

Now when we make a BOM all that gets included.

How's that sound? How do you handle keeping track of non-electronic
parts on a PCB?

On Sunday, December 4, 2022 at 6:35:28 PM UTC-5, John Larkin wrote:
> In our schematic entry software, PADS_LOGIC, we assign an attribute to
> every part on a schematic, namely our 7-digit stock number, and the
> program generates a BOM in our preferred format. That's cool.
>
> But every board has parts that are not usually on the schematic:
> screws, nuts, lockwashers, spacers, brackets, stickers, tie-wraps,
> glue, heat sinks, light pipes, and of course the PCB itself.
>
> I was thinking of creating two new logic parts
>
> PCB the board. Ref desig PCB1
>
> M any mechanical part that wouldn't normally appear on the sch
> ref desigs M1, M2, etc
>
> which would just look like little boxes on the schematic and have no
> PCB decal. Each would get the right stock number attribute.
>
> On the last page of every schematic we'd put the PCB mounting holes,
> fiducials, the PCB itself, and as many M's as we need. Good place to
> plop any useful notes too.
>
> Now when we make a BOM all that gets included.
>
> How's that sound? How do you handle keeping track of non-electronic
> parts on a PCB?

You need to remove all those "parts" from the files you give the assembly house. They won't know what to do with them.

In most companies, this is handled by having another level of assembly. So you'd have a bare board, and an assembled board. The assembled board would have a parts list that included the components that are soldered on, as well as the other parts that are bolted, glued or tied to the assembly. No place I've ever worked put these "other" parts in the electronic parts list.. Even elements like fiducial marks, need to be removed from the BoM.

--

Rick C.

- Get 1,000 miles of free Supercharging
- Tesla referral code - https://ts.la/richard11209

mandag den 5. december 2022 kl. 00.59.12 UTC+1 skrev Ricky:
> On Sunday, December 4, 2022 at 6:35:28 PM UTC-5, John Larkin wrote:
> > In our schematic entry software, PADS_LOGIC, we assign an attribute to
> > every part on a schematic, namely our 7-digit stock number, and the
> > program generates a BOM in our preferred format. That's cool.
> >
> > But every board has parts that are not usually on the schematic:
> > screws, nuts, lockwashers, spacers, brackets, stickers, tie-wraps,
> > glue, heat sinks, light pipes, and of course the PCB itself.
> >
> > I was thinking of creating two new logic parts
> >
> > PCB the board. Ref desig PCB1
> >
> > M any mechanical part that wouldn't normally appear on the sch
> > ref desigs M1, M2, etc
> >
> > which would just look like little boxes on the schematic and have no
> > PCB decal. Each would get the right stock number attribute.
> >
> > On the last page of every schematic we'd put the PCB mounting holes,
> > fiducials, the PCB itself, and as many M's as we need. Good place to
> > plop any useful notes too.
> >
> > Now when we make a BOM all that gets included.
> >
> > How's that sound? How do you handle keeping track of non-electronic
> > parts on a PCB?
> You need to remove all those "parts" from the files you give the assembly house. They won't know what to do with them.

they'd be marked "not mounted" just like any other option part

>
> In most companies, this is handled by having another level of assembly. So you'd have a bare board, and an assembled board. The assembled board would have a parts list that included the components that are soldered on, as well as the other parts that are bolted, glued or tied to the assembly. No place I've ever worked put these "other" parts in the electronic parts list. Even elements like fiducial marks, need to be removed from the BoM.
>

so there is already a procedure in place for thing the shouldn't be mounted like fiducials, mounting holes, optional parts etc.

On Sun, 4 Dec 2022 16:06:46 -0800 (PST), Lasse Langwadt Christensen
<langwadt@fonz.dk> wrote:

>mandag den 5. december 2022 kl. 00.59.12 UTC+1 skrev Ricky:
>> On Sunday, December 4, 2022 at 6:35:28 PM UTC-5, John Larkin wrote:
>> > In our schematic entry software, PADS_LOGIC, we assign an attribute to
>> > every part on a schematic, namely our 7-digit stock number, and the
>> > program generates a BOM in our preferred format. That's cool.
>> >
>> > But every board has parts that are not usually on the schematic:
>> > screws, nuts, lockwashers, spacers, brackets, stickers, tie-wraps,
>> > glue, heat sinks, light pipes, and of course the PCB itself.
>> >
>> > I was thinking of creating two new logic parts
>> >
>> > PCB the board. Ref desig PCB1
>> >
>> > M any mechanical part that wouldn't normally appear on the sch
>> > ref desigs M1, M2, etc
>> >
>> > which would just look like little boxes on the schematic and have no
>> > PCB decal. Each would get the right stock number attribute.
>> >
>> > On the last page of every schematic we'd put the PCB mounting holes,
>> > fiducials, the PCB itself, and as many M's as we need. Good place to
>> > plop any useful notes too.
>> >
>> > Now when we make a BOM all that gets included.
>> >
>> > How's that sound? How do you handle keeping track of non-electronic
>> > parts on a PCB?
>> You need to remove all those "parts" from the files you give the assembly house. They won't know what to do with them.
>
>they'd be marked "not mounted" just like any other option part
>
>>
>> In most companies, this is handled by having another level of assembly. So you'd have a bare board, and an assembled board. The assembled board would have a parts list that included the components that are soldered on, as well as the other parts that are bolted, glued or tied to the assembly. No place I've ever worked put these "other" parts in the electronic parts list. Even elements like fiducial marks, need to be removed from the BoM.
>>
>
>so there is already a procedure in place for thing the shouldn't be mounted like fiducials, mounting holes, optional parts etc.

Sometimes we have visible parts on the schematic that are not used,
like a resistor or a zero-ohm jumper, a placeholder just in case. Or
we have parts that are used on engineering units only, like test
connectors. We can set their "MAX" (stock number) attribute to "n/a"
or "engr", and they are still accounted for and handled properly.

If we hack the rev A BOM to add in parts that are not on the sch, the
list of such parts is sort of off to the side somewhere, things that
somebody has to remember. And if we spin the board to rev B, we have
to remember to include them again, ad hoc.

I think having everything on the schematic controls all those
otherwise invisible parts.

On Sun, 04 Dec 2022 15:35:17 -0800, John Larkin
<jlarkin@highlandSNIPMEtechnology.com> wrote:

>
>In our schematic entry software, PADS_LOGIC, we assign an attribute to
>every part on a schematic, namely our 7-digit stock number, and the
>program generates a BOM in our preferred format. That's cool.
>
>But every board has parts that are not usually on the schematic:
>screws, nuts, lockwashers, spacers, brackets, stickers, tie-wraps,
>glue, heat sinks, light pipes, and of course the PCB itself.
>
>I was thinking of creating two new logic parts
>
>PCB the board. Ref desig PCB1
>
>M any mechanical part that wouldn't normally appear on the sch
> ref desigs M1, M2, etc
>
>which would just look like little boxes on the schematic and have no
>PCB decal. Each would get the right stock number attribute.
>
>On the last page of every schematic we'd put the PCB mounting holes,
>fiducials, the PCB itself, and as many M's as we need. Good place to
>plop any useful notes too.
>
>Now when we make a BOM all that gets included.
>
>How's that sound? How do you handle keeping track of non-electronic
>parts on a PCB?

Subassemblies.

RL

On 04/12/2022 23:35, John Larkin wrote:
<snip>
>
> But every board has parts that are not usually on the schematic:
> screws, nuts, lockwashers, spacers, brackets, stickers, tie-wraps,
> glue, heat sinks, light pipes, and of course the PCB itself.
>

We (well, the bloke who does the tidy official schematics) put all those
on including a spiral to represent solder with its type. It seemed a
bit over the top at first, but I suppose it's rigorous.

--
Cheers
Clive

On Sunday, December 4, 2022 at 6:35:28 PM UTC-5, John Larkin wrote:
> In our schematic entry software, PADS_LOGIC, we assign an attribute to
> every part on a schematic, namely our 7-digit stock number, and the
> program generates a BOM in our preferred format. That's cool.
>
> But every board has parts that are not usually on the schematic:
> screws, nuts, lockwashers, spacers, brackets, stickers, tie-wraps,
> glue, heat sinks, light pipes, and of course the PCB itself.
>
> I was thinking of creating two new logic parts
>
> PCB the board. Ref desig PCB1
>
> M any mechanical part that wouldn't normally appear on the sch
> ref desigs M1, M2, etc
>
> which would just look like little boxes on the schematic and have no
> PCB decal. Each would get the right stock number attribute.
>
> On the last page of every schematic we'd put the PCB mounting holes,
> fiducials, the PCB itself, and as many M's as we need. Good place to
> plop any useful notes too.
>
> Now when we make a BOM all that gets included.
>
> How's that sound? How do you handle keeping track of non-electronic
> parts on a PCB?

Architectural drafting has been dealing with this problem for thousands of years, it's called detail drawing. So they make a notation on higher level drawings to see such and such detail drawing. The detail drawings can be very simple to very complex. The detail shows exactly how things are arranged..

In the Roman era the architect was required to stand beneath the structure when the formworks were removed, to demonstrate complete confidence in the finished product, and possibly eliminate poor performers from the trade.

On Mon, 05 Dec 2022 08:43:37 -0500, legg <legg@nospam.magma.ca> wrote:

>On Sun, 04 Dec 2022 15:35:17 -0800, John Larkin
><jlarkin@highlandSNIPMEtechnology.com> wrote:
>
>>
>>In our schematic entry software, PADS_LOGIC, we assign an attribute to
>>every part on a schematic, namely our 7-digit stock number, and the
>>program generates a BOM in our preferred format. That's cool.
>>
>>But every board has parts that are not usually on the schematic:
>>screws, nuts, lockwashers, spacers, brackets, stickers, tie-wraps,
>>glue, heat sinks, light pipes, and of course the PCB itself.
>>
>>I was thinking of creating two new logic parts
>>
>>PCB the board. Ref desig PCB1
>>
>>M any mechanical part that wouldn't normally appear on the sch
>> ref desigs M1, M2, etc
>>
>>which would just look like little boxes on the schematic and have no
>>PCB decal. Each would get the right stock number attribute.
>>
>>On the last page of every schematic we'd put the PCB mounting holes,
>>fiducials, the PCB itself, and as many M's as we need. Good place to
>>plop any useful notes too.
>>
>>Now when we make a BOM all that gets included.
>>
>>How's that sound? How do you handle keeping track of non-electronic
>>parts on a PCB?
>
>Subassemblies.
>
>RL

Suppose you sell a box with a board inside, and it ships with a cable
and a wall wart. What's the product structure?

On Mon, 5 Dec 2022 14:13:30 +0000, Clive Arthur
<clive@nowaytoday.co.uk> wrote:

>On 04/12/2022 23:35, John Larkin wrote:
><snip>
>>
>> But every board has parts that are not usually on the schematic:
>> screws, nuts, lockwashers, spacers, brackets, stickers, tie-wraps,
>> glue, heat sinks, light pipes, and of course the PCB itself.
>>
>
>We (well, the bloke who does the tidy official schematics) put all those
>on including a spiral to represent solder with its type. It seemed a
>bit over the top at first, but I suppose it's rigorous.

Being reasonable is good engineering.

Our manufacturing people have procedures for soldering and cleaning
and all that. They know that parts have to be soldered. I wouldn't try
to put all that into a little block on the schematic. But I might want
to convey the type of heat sink and nuts and screws and lockwashers.
It's got to be documented somewhere.

Some people here seem to be saying the equivalent of "we just do it."
I was wondering if we could include these things on the schematic and
in the auto-generated BOM from the first, and have that be in a known
place, initially and over revisions.

One could add notes "Screw head on top, nut and l/w bottom" or
whatever. Or call out the MAX number of some glue, quantity a/r, note
"GLUE LM45 TO COOLER" , things that I decide during the schematic
entry and have a place to save.

In other words, a schematic need not be restricted to only
electronically active parts.

On Mon, 5 Dec 2022 07:00:35 -0800 (PST), Fred Bloggs
<bloggs.fredbloggs.fred@gmail.com> wrote:

>On Sunday, December 4, 2022 at 6:35:28 PM UTC-5, John Larkin wrote:
>> In our schematic entry software, PADS_LOGIC, we assign an attribute to
>> every part on a schematic, namely our 7-digit stock number, and the
>> program generates a BOM in our preferred format. That's cool.
>>
>> But every board has parts that are not usually on the schematic:
>> screws, nuts, lockwashers, spacers, brackets, stickers, tie-wraps,
>> glue, heat sinks, light pipes, and of course the PCB itself.
>>
>> I was thinking of creating two new logic parts
>>
>> PCB the board. Ref desig PCB1
>>
>> M any mechanical part that wouldn't normally appear on the sch
>> ref desigs M1, M2, etc
>>
>> which would just look like little boxes on the schematic and have no
>> PCB decal. Each would get the right stock number attribute.
>>
>> On the last page of every schematic we'd put the PCB mounting holes,
>> fiducials, the PCB itself, and as many M's as we need. Good place to
>> plop any useful notes too.
>>
>> Now when we make a BOM all that gets included.
>>
>> How's that sound? How do you handle keeping track of non-electronic
>> parts on a PCB?
>
>Architectural drafting has been dealing with this problem for thousands of years, it's called detail drawing. So they make a notation on higher level drawings to see such and such detail drawing. The detail drawings can be very simple to very complex. The detail shows exactly how things are arranged.

That works but needs multiple higher level (or side detail) drawings
and nested BOMs. And it requires both to be developed concurrently. It
would be easier for me to put the non-electronic bits on the schematic
from the start. AThay gets the loose stuff into the BOM from the
start.

We name the firmware on a pcb BOM too.

>
>In the Roman era the architect was required to stand beneath the structure when the formworks were removed, to demonstrate complete confidence in the finished product, and possibly eliminate poor performers from the trade.

The Romans didn't make PC boards.

I think the confusion here is that you seem to be equating the BOM and the schematic. A schematic can have multiple BOMs. Yes, I put non-electrical parts on the schematic. The schematic is used by technicians and engineers trouble shooting the board. The BOM is used by manufacturering people who may never see the schematic. You can have a BOM with the part numbers of the PCB assembly with an empty socket, the programmable IC, the program, programming instructions and the label. The part number of the programmable IC is on the schematic as well as the socket. The BOM generated from the schematic is just the starting point. From there you generate assembly BOMs, assembly instructions, and assembly drawings.

On Mon, 05 Dec 2022 12:25:27, Wanderer@noplace.com wrote:

>I think the confusion here is that you seem to be equating the BOM and the schematic.

As noted, our layout software generates the BOM from the schematic.
There can be multiple BOMs for one PCB, as for instance dash-number
versions, and they have to be managed manually. But may as well take
care of all the common stuff.

> A schematic can have multiple BOMs. Yes, I put non-electrical parts on the schematic. The schematic is used by technicians and engineers trouble shooting the board. The BOM is used by manufacturering people who may never see the schematic. You can have a BOM with the part numbers of the PCB assembly with an empty socket, the programmable IC, the program, programming instructions and the label. The part number of the programmable IC is on the schematic as well as the socket. The BOM generated from the schematic is just the starting point. From there you generate assembly BOMs, assembly instructions, and assembly drawings.

One recent case is that there is a fuseholder on the schematic. We
created a new part for the fuse itself, and put that on the schamatic,
floating right next to the fuseholder. The fuse part has no pins; it's
just a graphic with a stock number attribute, so it gets on the BOM
automagically.

On 12/4/22 7:19 PM, John Larkin wrote:
> On Sun, 4 Dec 2022 16:06:46 -0800 (PST), Lasse Langwadt Christensen
> <langwadt@fonz.dk> wrote:
>
>> mandag den 5. december 2022 kl. 00.59.12 UTC+1 skrev Ricky:
>>> On Sunday, December 4, 2022 at 6:35:28 PM UTC-5, John Larkin wrote:
>>>> In our schematic entry software, PADS_LOGIC, we assign an attribute to
>>>> every part on a schematic, namely our 7-digit stock number, and the
>>>> program generates a BOM in our preferred format. That's cool.
>>>>
>>>> But every board has parts that are not usually on the schematic:
>>>> screws, nuts, lockwashers, spacers, brackets, stickers, tie-wraps,
>>>> glue, heat sinks, light pipes, and of course the PCB itself.
>>>>
>>>> I was thinking of creating two new logic parts
>>>>
>>>> PCB the board. Ref desig PCB1
>>>>
>>>> M any mechanical part that wouldn't normally appear on the sch
>>>> ref desigs M1, M2, etc
>>>>
>>>> which would just look like little boxes on the schematic and have no
>>>> PCB decal. Each would get the right stock number attribute.
>>>>
>>>> On the last page of every schematic we'd put the PCB mounting holes,
>>>> fiducials, the PCB itself, and as many M's as we need. Good place to
>>>> plop any useful notes too.
>>>>
>>>> Now when we make a BOM all that gets included.
>>>>
>>>> How's that sound? How do you handle keeping track of non-electronic
>>>> parts on a PCB?
>>> You need to remove all those "parts" from the files you give the assembly house. They won't know what to do with them.
>>
>> they'd be marked "not mounted" just like any other option part
>>

That's what I do, "DNP" for do not populate.

>>>
>>> In most companies, this is handled by having another level of assembly. So you'd have a bare board, and an assembled board. The assembled board would have a parts list that included the components that are soldered on, as well as the other parts that are bolted, glued or tied to the assembly. No place I've ever worked put these "other" parts in the electronic parts list. Even elements like fiducial marks, need to be removed from the BoM.
>>>
>>
>> so there is already a procedure in place for thing the shouldn't be mounted like fiducials, mounting holes, optional parts etc.
>
> Sometimes we have visible parts on the schematic that are not used,
> like a resistor or a zero-ohm jumper, a placeholder just in case. Or
> we have parts that are used on engineering units only, like test
> connectors. We can set their "MAX" (stock number) attribute to "n/a"
> or "engr", and they are still accounted for and handled properly.
>
> If we hack the rev A BOM to add in parts that are not on the sch, the
> list of such parts is sort of off to the side somewhere, things that
> somebody has to remember. And if we spin the board to rev B, we have
> to remember to include them again, ad hoc.
>
> I think having everything on the schematic controls all those
> otherwise invisible parts.
>

It isn't very customary though because screws, nuts and washers are
typically considered system assembly parts, not board assembly parts.
Unless it is a heat sink, shield or something that becomes an integral
part of the finished "ready-to-install" board. However, then they are
not DNP to begin with.

At one company they had a small bag of gummibears in the BOM because
back then they weren't available in the US but there were in Europe
where the boards were made. It worked but only until customs had a cow
about it one day. Then the designer got read the riot act.

--
Regards, Joerg

http://www.analogconsultants.com/

On Mon, 5 Dec 2022 12:04:13 -0800, Joerg <news@analogconsultants.com>
wrote:

>On 12/4/22 7:19 PM, John Larkin wrote:
>> On Sun, 4 Dec 2022 16:06:46 -0800 (PST), Lasse Langwadt Christensen
>> <langwadt@fonz.dk> wrote:
>>
>>> mandag den 5. december 2022 kl. 00.59.12 UTC+1 skrev Ricky:
>>>> On Sunday, December 4, 2022 at 6:35:28 PM UTC-5, John Larkin wrote:
>>>>> In our schematic entry software, PADS_LOGIC, we assign an attribute to
>>>>> every part on a schematic, namely our 7-digit stock number, and the
>>>>> program generates a BOM in our preferred format. That's cool.
>>>>>
>>>>> But every board has parts that are not usually on the schematic:
>>>>> screws, nuts, lockwashers, spacers, brackets, stickers, tie-wraps,
>>>>> glue, heat sinks, light pipes, and of course the PCB itself.
>>>>>
>>>>> I was thinking of creating two new logic parts
>>>>>
>>>>> PCB the board. Ref desig PCB1
>>>>>
>>>>> M any mechanical part that wouldn't normally appear on the sch
>>>>> ref desigs M1, M2, etc
>>>>>
>>>>> which would just look like little boxes on the schematic and have no
>>>>> PCB decal. Each would get the right stock number attribute.
>>>>>
>>>>> On the last page of every schematic we'd put the PCB mounting holes,
>>>>> fiducials, the PCB itself, and as many M's as we need. Good place to
>>>>> plop any useful notes too.
>>>>>
>>>>> Now when we make a BOM all that gets included.
>>>>>
>>>>> How's that sound? How do you handle keeping track of non-electronic
>>>>> parts on a PCB?
>>>> You need to remove all those "parts" from the files you give the assembly house. They won't know what to do with them.
>>>
>>> they'd be marked "not mounted" just like any other option part
>>>
>
>That's what I do, "DNP" for do not populate.
>
>>>>
>>>> In most companies, this is handled by having another level of assembly. So you'd have a bare board, and an assembled board. The assembled board would have a parts list that included the components that are soldered on, as well as the other parts that are bolted, glued or tied to the assembly. No place I've ever worked put these "other" parts in the electronic parts list. Even elements like fiducial marks, need to be removed from the BoM.
>>>>
>>>
>>> so there is already a procedure in place for thing the shouldn't be mounted like fiducials, mounting holes, optional parts etc.
>>
>> Sometimes we have visible parts on the schematic that are not used,
>> like a resistor or a zero-ohm jumper, a placeholder just in case. Or
>> we have parts that are used on engineering units only, like test
>> connectors. We can set their "MAX" (stock number) attribute to "n/a"
>> or "engr", and they are still accounted for and handled properly.
>>
>> If we hack the rev A BOM to add in parts that are not on the sch, the
>> list of such parts is sort of off to the side somewhere, things that
>> somebody has to remember. And if we spin the board to rev B, we have
>> to remember to include them again, ad hoc.
>>
>> I think having everything on the schematic controls all those
>> otherwise invisible parts.
>>
>
>It isn't very customary though because screws, nuts and washers are
>typically considered system assembly parts, not board assembly parts.
>Unless it is a heat sink, shield or something that becomes an integral
>part of the finished "ready-to-install" board. However, then they are
>not DNP to begin with.

A PCB assembly has a stock number and an assembly drawing here. If a
part is inherently on the board, like a heat sink or a fuse, it and
its mounting hardware are considered to be part of the PCA so are on
the BOM. All that gets assembled and inspected and usually subassembly
tested.

If engineering produces a drawing and BOM, we describe the end result
and let manufacturing decide how to stage assembly.
If that board is mounted into a chassis with spacers and screws, we
put those parts on the chassis drawing and BOM, the next higher
assembly.

>
>At one company they had a small bag of gummibears in the BOM because
>back then they weren't available in the US but there were in Europe
>where the boards were made. It worked but only until customs had a cow
>about it one day. Then the designer got read the riot act.

Some guys at one NASA facility, the Michaud plant in New Orleans,
designed an audio amp and had some manufactured there with all the
usual NASA parts and standards. It was reported to be a very bad amp.

On Mon, 05 Dec 2022 07:30:42 -0800, John Larkin
<jlarkin@highlandSNIPMEtechnology.com> wrote:

>On Mon, 05 Dec 2022 08:43:37 -0500, legg <legg@nospam.magma.ca> wrote:
>
>>On Sun, 04 Dec 2022 15:35:17 -0800, John Larkin
>><jlarkin@highlandSNIPMEtechnology.com> wrote:
>>
>>>
>>>In our schematic entry software, PADS_LOGIC, we assign an attribute to
>>>every part on a schematic, namely our 7-digit stock number, and the
>>>program generates a BOM in our preferred format. That's cool.
>>>
>>>But every board has parts that are not usually on the schematic:
>>>screws, nuts, lockwashers, spacers, brackets, stickers, tie-wraps,
>>>glue, heat sinks, light pipes, and of course the PCB itself.
>>>
>>>I was thinking of creating two new logic parts
>>>
>>>PCB the board. Ref desig PCB1
>>>
>>>M any mechanical part that wouldn't normally appear on the sch
>>> ref desigs M1, M2, etc
>>>
>>>which would just look like little boxes on the schematic and have no
>>>PCB decal. Each would get the right stock number attribute.
>>>
>>>On the last page of every schematic we'd put the PCB mounting holes,
>>>fiducials, the PCB itself, and as many M's as we need. Good place to
>>>plop any useful notes too.
>>>
>>>Now when we make a BOM all that gets included.
>>>
>>>How's that sound? How do you handle keeping track of non-electronic
>>>parts on a PCB?
>>
>>Subassemblies.
>>
>>RL
>
>Suppose you sell a box with a board inside, and it ships with a cable
>and a wall wart. What's the product structure?

depends on what the purchase order looks like - whether
the accessories are options or part of a sales package
with single part number.

RL

On Mon, 05 Dec 2022 07:30:42 -0800, John Larkin
<jlarkin@highlandSNIPMEtechnology.com> wrote:

>On Mon, 05 Dec 2022 08:43:37 -0500, legg <legg@nospam.magma.ca> wrote:
>
>>On Sun, 04 Dec 2022 15:35:17 -0800, John Larkin
>><jlarkin@highlandSNIPMEtechnology.com> wrote:
>>
>>>
>>>In our schematic entry software, PADS_LOGIC, we assign an attribute to
>>>every part on a schematic, namely our 7-digit stock number, and the
>>>program generates a BOM in our preferred format. That's cool.
>>>
>>>But every board has parts that are not usually on the schematic:
>>>screws, nuts, lockwashers, spacers, brackets, stickers, tie-wraps,
>>>glue, heat sinks, light pipes, and of course the PCB itself.
>>>
>>>I was thinking of creating two new logic parts
>>>
>>>PCB the board. Ref desig PCB1
>>>
>>>M any mechanical part that wouldn't normally appear on the sch
>>> ref desigs M1, M2, etc
>>>
>>>which would just look like little boxes on the schematic and have no
>>>PCB decal. Each would get the right stock number attribute.
>>>
>>>On the last page of every schematic we'd put the PCB mounting holes,
>>>fiducials, the PCB itself, and as many M's as we need. Good place to
>>>plop any useful notes too.
>>>
>>>Now when we make a BOM all that gets included.
>>>
>>>How's that sound? How do you handle keeping track of non-electronic
>>>parts on a PCB?
>>
>>Subassemblies.
>>
>>RL
>
>Suppose you sell a box with a board inside, and it ships with a cable
>and a wall wart. What's the product structure?

I had fun with this in companies at their early stages of 'part
numbering' a BOM. You could tell from the part number what stage
of the mfring process it could be found in, and where it could
be found.

Top level included packing material, labels etc.

Compeeyoodah limits determined the number of possible fields in MRP

IBM and xerox just issued numbers at random. That works too, if
the slaves can access a computer terminal.

RL

On Mon, 05 Dec 2022 08:43:37 -0500, legg <legg@nospam.magma.ca> wrote:

>On Sun, 04 Dec 2022 15:35:17 -0800, John Larkin
><jlarkin@highlandSNIPMEtechnology.com> wrote:
>
>>
>>In our schematic entry software, PADS_LOGIC, we assign an attribute to
>>every part on a schematic, namely our 7-digit stock number, and the
>>program generates a BOM in our preferred format. That's cool.
>>
>>But every board has parts that are not usually on the schematic:
>>screws, nuts, lockwashers, spacers, brackets, stickers, tie-wraps,
>>glue, heat sinks, light pipes, and of course the PCB itself.
>>
>>I was thinking of creating two new logic parts
>>
>>PCB the board. Ref desig PCB1
>>
>>M any mechanical part that wouldn't normally appear on the sch
>> ref desigs M1, M2, etc
>>
>>which would just look like little boxes on the schematic and have no
>>PCB decal. Each would get the right stock number attribute.
>>
>>On the last page of every schematic we'd put the PCB mounting holes,
>>fiducials, the PCB itself, and as many M's as we need. Good place to
>>plop any useful notes too.
>>
>>Now when we make a BOM all that gets included.
>>
>>How's that sound? How do you handle keeping track of non-electronic
>>parts on a PCB?
>
>Subassemblies.
>
>RL

So if you add one screw to a board, you have a drawing and a BOM for
the board, and a next-higher-assy drawing and BOM for the board+screw.

Deep.

On Tue, 06 Dec 2022 16:45:05 -0800, John Larkin
<jlarkin@highland_atwork_technology.com> wrote:

>On Mon, 05 Dec 2022 08:43:37 -0500, legg <legg@nospam.magma.ca> wrote:
>
>>On Sun, 04 Dec 2022 15:35:17 -0800, John Larkin
>><jlarkin@highlandSNIPMEtechnology.com> wrote:
>>
>>>
>>>In our schematic entry software, PADS_LOGIC, we assign an attribute to
>>>every part on a schematic, namely our 7-digit stock number, and the
>>>program generates a BOM in our preferred format. That's cool.
>>>
>>>But every board has parts that are not usually on the schematic:
>>>screws, nuts, lockwashers, spacers, brackets, stickers, tie-wraps,
>>>glue, heat sinks, light pipes, and of course the PCB itself.
>>>
>>>I was thinking of creating two new logic parts
>>>
>>>PCB the board. Ref desig PCB1
>>>
>>>M any mechanical part that wouldn't normally appear on the sch
>>> ref desigs M1, M2, etc
>>>
>>>which would just look like little boxes on the schematic and have no
>>>PCB decal. Each would get the right stock number attribute.
>>>
>>>On the last page of every schematic we'd put the PCB mounting holes,
>>>fiducials, the PCB itself, and as many M's as we need. Good place to
>>>plop any useful notes too.
>>>
>>>Now when we make a BOM all that gets included.
>>>
>>>How's that sound? How do you handle keeping track of non-electronic
>>>parts on a PCB?
>>
>>Subassemblies.
>>
>>RL
>
>So if you add one screw to a board, you have a drawing and a BOM for
>the board, and a next-higher-assy drawing and BOM for the board+screw.
>
>Deep.

If the screw only goes into the board, it should be in the board
assembly, probably before refolw or wave.

If the screw attaches the board to a box, then the box, screw and
board are in a 'testable' (?) or 'final' assembly, which likely
includes a few other bits. Some common sense is required here.
Imagine that it's your job just to put in that screw.

Depends on your in-house processes and how close you are to actually
filling a purchase order.

RL