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I have no experience of dealing with the PCB manufacturers except the time that I once used PCBWay's service. I would like to know if there are some standard PCB board sizes that one needs to create when getting a custom PCB made?

My basic idea is to not incur extra cost for the loss of the material PCB Manufacturer faces. For example, Let's say they use a Board of 10*10 Inch to manufacture and I submit a custom board request with dimension of 7*7 Inch, Does that increase cost of PCB?

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    \$\begingroup\$ Apart from a trivial "no" this question is not specifically answerable within the rules of SE sites - in particular questions that could only be answered with a list are not permitted. A given vendor may have a particular "up to size X" deal but this is unique to that vendor. Apart from exotic materials or requirements actual panel sizes fabricated are huge and include many unrelated boards. \$\endgroup\$ – Chris Stratton Jan 20 '18 at 17:17
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    \$\begingroup\$ Yeah, I have seen those upto X size, So I can get a X/2,X/4 sized pcb. But what if I do some unconventional size and shape, will I have to bear the cost for that? Is that question still out of rules of SE? If yes, I'll happily delete. \$\endgroup\$ – MaNyYaCk Jan 20 '18 at 17:22
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    \$\begingroup\$ Check with your PC manufacturer. They produce multiple boards on a panel of a fixed size, then cut them to your dimensions, so they almost always make a full panel of boards no matter how many you order. You can talk to them and get an idea of an optimum size so they can get the best use of their panel. \$\endgroup\$ – John Birckhead Jan 20 '18 at 17:24
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    \$\begingroup\$ Generally in high volume it is the total mass of copper that is the cost driver for simple boards. weight * area* layers \$\endgroup\$ – Sunnyskyguy EE75 Jan 20 '18 at 17:26
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    \$\begingroup\$ Possible duplicate of Is there a standard PCB Array Size for PCB Assembly? \$\endgroup\$ – Passerby Jan 20 '18 at 17:59
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What's important to the fabrication shop is not the size of the individual board, but the size of the panel it will be made in. Meaning, typically PCBs are made with multiple images on a panel, and then cut apart either before delivery or after component assembly.

And, yes, there are (semi-)standard panel sizes.

Among those standards, different shops will be set up for different ones. However, every shop I know offers 18 x 24 inches as a standard size.

There are lots of other sizes available, so if 18 x 24 doesn't work for you, contact your shop to see what else they offer.

If the total area of your order (plus some allowances I'll mention below) is less than the smallest panel your vendor can handle, you'll end up paying for some waste. If you try to absolutely maximize the usage of a panel, the vendor is likely to run one extra panel to allow them to still deliver your order if there's a defect in one location, and again you'll pay (a fairly small amount) for this extra panel to be made and then discarded. If you design your board to fit (for example) 12 to a panel, and then only order 10 boards, you're likely to get about the best pricing you can hope for.

When deciding how to panelize your board, you also need to consider the routing allowance needed between the boards and gutter allowance along the edges to allow for handling. In my experience, typical minimums for these are 0.2 and 0.25 inches, but different shops may have different requirements, so confirm this with your shop.

If the boards will be assembled (pick & place'd) in panel form, you should also verify the edge gutter requirement with your assembly shop.

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  • \$\begingroup\$ I accidentally left the edge outline off a PCB and the manufacturer put (presumably the smallest they could make) tooling strip on there - about 3.5mm from the V-groove. \$\endgroup\$ – Spehro Pefhany Jan 20 '18 at 17:55
  • \$\begingroup\$ @SpehroPefhany, and then your assembly shop likely charged a special handling or NRE fee to make carriers for those boards. \$\endgroup\$ – The Photon Jan 20 '18 at 17:58
  • \$\begingroup\$ They didn't charge anything extra as it was a turnkey assembly PCB deal. ;-) It did make later handling a bit more difficult. \$\endgroup\$ – Spehro Pefhany Jan 20 '18 at 18:01
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Sometimes PCB makers have a per-panel price. They will tell you the size they are using..or more importantly, what area you have to work with-- usually usable area (not panel size) is at least 10" x 16", maybe up to 10.5" x 16.5" or a bit more. That would be a small panel. For large production I believe larger panels are more typical. Typically phenolic single sided boards use much larger panel sizes. This reference lists typical standard PCB panel sizes as follows:

enter image description here

Panel borders (maybe 0.5" on each side) take away from that area.

It is not particularly important unless your PCBs (or your self-panelized PCBs) are getting up to the size where you only get a few from a panel- materials are not really the biggest part of the PCB cost in prototype volumes despite you being charged per square cm or inch. If your PCB or panel is approaching or exceeding about a letter-size or A4 sheet and your quantities are more than hundreds (of that size, it could be thousands of panelized boards) it might be worth worrying about.

When you order loose boards you don't have to pay for router kerf and tooling strips either as PCB area (well, you do but it's not figured directly into the costs) or as shipping mass, but extra costs are incurred later.

It might be interesting to play with the online calculators that many PCB makers have and see if panelization figures into their calculations. You would expect the cost per square inch to not follow a straight line as the size gets bigger. Keep in mind though that getting large defect-free areas gets more expensive as the area increases so a large panel (without X-outs permitted) may be more expensive per square inch than a smaller panel. It may not be important if the technology level is low, but for multilayer boards with fine pitch and tiny holes it is not negligible. Often the online quotes are not the final quote in such cases, and they will come back with an adjusted quote (hint: it is never lower).

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to not incur extra cost for the loss of the material PCB Manufacturer faces

I think this is your key assumption which I would challenge. While it is great that you care about other people and nature not to waste the materials, I am afraid that it is simply out of your control in this case.

Each square inch of the board is a cost for PCB house. They strive to minimize losses, they combine boards on the sheets, rotate them, use other tricks.

Since PCB manufacturing is nothing than just a business, what you primary would care about is your - end customer - price for their end product - the PCB. And of course less board size should (usually) lead to less variable cost (the cost which really depends on the production of your board - for example, FR4 material sheet size, amount of mask, etc).

In general, if you are still curious beyond the price as indication of the manufacturer's usage of materials (and their quality :) you always can ask them which equipment they use, how they use it, what they do with your Gerber files etc, but I bet they will try not to disclose much of this info because usually this information is not for your eyes as a customer.

Update: as @BeB00 summarized in the comment

so the correct answer is to just get quotes for different sizes and see

and I would add to it that you must design your board so that device would work as expected, can be mounted into place, and be serviceable (if possible). Trying to stick to some size without real product requirement, from my point of view, is nonsense.

Respectable PCB houses usually advise their clients on the quality of their Gerber designs, and even tell clients if there're any elements which can be changed to (a) decrease production cost/minimize productions issues, and thus (b) decrease total cost for customer.

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  • \$\begingroup\$ I think OP is asking if there's a standard size because OP doesn't want to pay for the wastage, rather than worrying about the manufacturer's profit margin \$\endgroup\$ – BeB00 Jan 20 '18 at 17:46
  • \$\begingroup\$ And here I say that it anyway is out of control for the customer. None will share this information for the same reason as will not share profit gained in the operations. \$\endgroup\$ – Anonymous Jan 20 '18 at 17:49
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    \$\begingroup\$ Right, so the correct answer is to just get quotes for different sizes and see \$\endgroup\$ – BeB00 Jan 20 '18 at 17:56
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The PCBWay website has an instant quote feature. This is not an estimator, this is the price you pay if you submit your order. All you need is to plug several different sizes and parameters, in panels or individual boards, and see yourself how the pricing goes.

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  • \$\begingroup\$ Actually it clearly says "Final price is subject to our review", and multilayer boards seem to attract surcharges (probably a different factory). \$\endgroup\$ – Spehro Pefhany Jan 20 '18 at 22:10
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    \$\begingroup\$ @SpehroPefhany, not really, their review is to check for manufacturability and DRC. If you don't do anything crazy, the price is right on. BTW, they are really good in catching mistakes and omissions/discrepancies between what you put into their web, and what is in your Gerber documentation, punctuality of their review is outstanding. \$\endgroup\$ – Ale..chenski Jan 21 '18 at 0:04

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