How to copper-plate laminate / How to make custom copper boards from scratch? - Page 1
Forum section: electronics / projects

author: mrflux
author_rank: Contributor
timestamp: April 14, 2015, 05:12:10 pm
content: Hi guys!I've been following EEVblog for some time and decided to test out the forums.I'm currently working on a project that requires a large amount of large surface areas of PCB, for example 100 square meters of PCB cut into 50x50cm. Currently, I'm looking at a price of about $50 per square meter. But I think I'll be able to do much better if I make it myself.I'm looking for a copper plating of at least 50 microns.Any ideas?My current idea is to coat the plastic with conductive ink and copper plate it. But I'm not sure how I can control the thickness (except for exposure time), or whether this is really a viable approach. Perhaps the copper will oxidate easily. The surface looks very different from ordinary PCB. Does ordinary PCB use an alloy?

author: tggzzz
author_rank: Super Contributor
timestamp: April 14, 2015, 05:31:38 pm
content: Quote from: mrflux on April 14, 2015, 05:12:10 pmWhat makes you think you will be more efficient (=> cheaper) than the professionals?If you are, then you've made your fortune - either you will put the existing manufacturers out of business or you can see you rexpersise to them.

author: mrflux
author_rank: Contributor
timestamp: April 14, 2015, 07:02:37 pm
content: Hi tggzzz,Let me clarify: The "PCB" manufacturers are extremely good at making high quality boards at small sizes, with many layers, with very high precision.What I'm looking for is basically to make LED panels which require single sided, single layer, big surfaces, low quality, thick copper, low precision specs.It's a completely different type of product than what they're offering. At least the way I see it.Additionally, as I see it, 99% of the cost of PCB manufacturing is in the photomasking, etching, drilling, plating, masking, SMT placing, testing and so on.I welcome any questions that may identify problems I haven't thought about until nowThanks!

author: max666
author_rank: Frequent Contributor
timestamp: April 14, 2015, 07:06:57 pm
content: Have you ever made a pcb from start to finish yourself? If not I think it could be an eye-opening experience.I wouldn't recommend you making 100 square meters pcb's yourself, because I think you aren't quite ready to handle all the required chemicals responsibly and environmentally correct (please correct me if I'm wrong).

author: PeterFW
author_rank: Frequent Contributor
timestamp: April 14, 2015, 07:16:38 pm
content: Quote from: mrflux on April 14, 2015, 05:12:10 pmMy idea would be to do the math!You need hundreds of liters of chemicals, a safe way to dispose of the contaminated waste, big tanks, heaters, flood light sized UV lamps, masks and so much more.I roughly estimate (read: pulled number out of my hat) you will end up with well over 2000 Liters of rather harmfull chemical waste material.There shurely will be a better solution to put a few LEDs out into the world.If noone else has done something like you, there will be a reason for it.Adressable LEDs strips, mudular boards, point to point wiring...

author: mrflux
author_rank: Contributor
timestamp: April 14, 2015, 07:44:31 pm
content: Great questions!Does anyone here source their own bare pcb? In what kind of quantities do you buy - and what prices? Less than $50 per sqm?Chemicals: The process seems quite simple and the chemicals seem to be recyclable. Zero waste.The boards would be in vertical baths, so I think the volume would be much less.Addressable LEDs: Yeah, but mounted on what?Modular boards: Not sure what you mean? Strips perhaps? That would reduce the surface area, but increase complexity.Point to point: Possible. But part of the cool thing about solid PCB is the heatsinking capability which prolongs LED lifespan.You would need heatsinking anyway.PCB from scratch: Yes, except for the first part of laminating/plating copper to a surface.Reason why noone has done it: Because they haven't needed to make this type of product before. Chinese manufacturers are doing something similar, but they seem to be mainly interested with mass production of standard types of products.This guy is doing something completely without chemicals

author: PeterFW
author_rank: Frequent Contributor
timestamp: April 14, 2015, 07:55:09 pm
content: Quote from: mrflux on April 14, 2015, 07:44:31 pmUhm... no?They get used up, 100L will only etch so many boards before they have to be replaced...How do you recycle the chemicals? How are they named, how do they work, how do you recycle them?QuoteSomething like this:http://www.cutedigi.com/images/LED_stip.JPGGlued to something like... you got me there, thin flat sheets of some kind?

author: mrflux
author_rank: Contributor
timestamp: April 14, 2015, 08:06:13 pm
content: We're talking plating, not etchingBut as for etching - yes, it's possible to take the copper you etched away and replate it.That's the beauty of the process. You can actually etch the panels and recycle the copper.Do you have any experience with plating that you could contribute with? I'd really love to hear from people who have tried to plate copper.This guy has laminated/glued copper foil onto glass. Which is another way to approach it - without chemical baths and so on.

author: mazurov
author_rank: Frequent Contributor
timestamp: April 14, 2015, 08:30:06 pm
content: You can bond copper foil to the fiberglass, that's how outer layers of PCB are made. Your cost will be the sum of costs of foil, fg, and glue. The cap'invetstment will be the price of a suitable press/oven. You then mill out isolation for your LEDs. I've done it some time ago, the results are quite good ->https://plus.google.com/+OlegMazurov/posts/jF18vokKdCpPCB offcuts (obviously much smaller than 50cm2, more like 3"x4", 4"x6") can be bought on eBay or from board houses much cheaper than $50/m2. In the US the price for offcuts of any flat material is based on amount of material that fits in some USPS flat rate box. You want 2oz copper on both sides of thin fiberglass, 0.02"-0.031" thickness is common and stil easy to work with. The board from the linked post also have milled slot in the middle to even out heat transfer.

author: Alex Eisenhut
author_rank: Super Contributor
timestamp: April 14, 2015, 08:39:26 pm
content: Quote from: mrflux on April 14, 2015, 08:06:13 pmStained glass hobby stores sell copper foil with adhesive backing. PCBs are usually built as a stack of fiberglass stock and foil shoved into a press (vast oversimplification). The only way to get decent adhesion is by the surface roughness of the foil "biting" into the wet epoxy/fiberglass.

author: edavid
author_rank: Super Contributor
timestamp: April 14, 2015, 08:44:19 pm
content: Quote from: mrflux on April 14, 2015, 07:02:37 pmThat's exactly what consumer electronics PCB fabs make, but 400 boards might be low volume for them.Also, if it's for LEDs, don't you need aluminum core boards?

author: PeterFW
author_rank: Frequent Contributor
timestamp: April 14, 2015, 08:49:00 pm
content: Quote from: mrflux on April 14, 2015, 08:06:13 pmWich still leaves you with the etchant and gasious electrolysis products.QuoteI have plated silver, nickel and gold at home, small scale.When i think of scaling that up to a square meters worth i would have to rent a place. I think you vastly underestimate the work.The only feaseable way of putting copper on bare FR4 or FR2 i can think of would be laminating etched copper foil with epoxy in a press, multiple stacks at once.A ton of heavy duty square tubing and home made hydraulics or a seriously big screw press.

author: atos
author_rank: Contributor
timestamp: April 14, 2015, 09:02:49 pm
content: Hi,if you have... say tinfoil, you might be able to use that as a base to electroplate a cooper surface to it, and then glue it to something more rigid. Have not verifiedthisproject, but the idea seems solid enough to be adapted to achieve your goal of making your own PCBs.On a side note, it should also be possible to make MCPCBs with this.Good luck!

author: sleemanj
author_rank: Super Contributor
timestamp: April 14, 2015, 09:05:36 pm
content: Pcb manufacturers do not plate the initial copper layer, it's a bonded copper sheet, plating is used after masking to build up the trace layers and do the (activated) holes.Blank copper clad board for your own etching is probably not plated at all, just bonded sheet.Plating is not the way to go.You would be better to purchase copper foil, a laminator, and a suitable adhesive.

author: mrflux
author_rank: Contributor
timestamp: April 14, 2015, 09:10:02 pm
content: mazurov: Right - I was thinking about routing as well as a simple (cheaper) way of isolation.+Alex Eisenhut- thanks for the links!I'm looking for high volume though, so hobby stores are out of the question. Basically I'm looking to mass produce a product that I'm working on, preferably with local sourcing. But feel free to post links to other sources as well, in case other people read this and are looking for low volume options.edavid: I've seen a ton of aluminium LED panels / pcbs. Basically they use a solid aluminum base, coated with mask, then coated with copper, then coated with white solder mask? The aluminum base is purely for heat transfer purposes?I've seen boards with aluminum coating also (or perhaps tin?). Any idea on how they handle the reflow on aluminum? Isn't it difficult to solder to aluminum?PeterFW: You're probably right, that laminating copper foil is an easier way to go. I just wanted to make sure that plating would be too complicated.I'm okay with investing at least $10k.It seems easy enough though:I'm more concerned with uneven thickness, poor adhesion of the copper to the base, poor solderability, breakage, oxidation etc.sleemanj: Yes I noticed that Eurocircuits specifically mentions using pre-bonded laminates (at 5:10)Any ideas about bendability of PCB? e.g. LED strips are quite flexible. At what point does this become a problem?Still, it would be interesting to go the plating-way, since it would allow custom shapes as well, including round objects.

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: April 14, 2015, 09:11:58 pm
content: Focus on your product, not reinventing the wheel. Once you take into account all the time, labour and equipment there is no way you will beat the people who have been doing this all day every day for years.

author: nctnico
author_rank: Super Contributor
timestamp: April 14, 2015, 09:19:25 pm
content: Quote from: PeterFW on April 14, 2015, 07:55:09 pmLook for CuCl etching (copper chloride). This process allows to use the same etchant for an unlimited amount of boards and time. You start with FeCl (ferric chloride) and add HCl (hydrochloric acid) when the FeCl starts to run out. This is where the FeCl etching process turns into an CuCl etching process.To the topic starter: There are cheaper board materials and cheaper etching processes. A Chinese firm is probably able to help you get this huge number of boards. I would not recommend making your own PCB material. You are likely to fail or at least waste a massive amount your time better spend working in the local supermarket.

author: atos
author_rank: Contributor
timestamp: April 14, 2015, 09:27:12 pm
content: Quote from: mikeselectricstuff on April 14, 2015, 09:11:58 pmThen again one shouldn't underestimate newcomers, they often have a different perspective. Doing things all day and everyday for years in similar ways, one tends to develop subconscious blinkers.

author: mrflux
author_rank: Contributor
timestamp: April 14, 2015, 09:30:40 pm
content: atos: Indeed. I realize that ball shaped PCB is not what I originally asked for - but imagine a nickel plated bowling ball... maybe it could be used for something. Not dodgeball...but something

author: edavid
author_rank: Super Contributor
timestamp: April 14, 2015, 09:34:21 pm
content: Quote from: mrflux on April 14, 2015, 09:10:02 pmRight.QuoteAluminum is never used for traces.P.S. Have you made a test board yet? Let's see it...

author: mrflux
author_rank: Contributor
timestamp: April 14, 2015, 10:31:14 pm
content: edadavid: Right. They seem to be using "immersion tin lead", which would be prohibited in the EU.I've tested the electroplating process, but I wasn't able to build up thickness. It just covered the material. However, I've acquired a nice textbook on the subject, so perhaps I'll have some results over the summer, while I try to work on the foil-bonding approach as well. I'm thinking to try to find a local workshop that does electroplating and use their equipment for testing the method first, before getting something I don't need etc.I'm quite pleased with the advice here. Thanks guys! O0http://www.ledlightpcb.com/photo/pl3924187-high_power_smd_3014_led_panel_pcb_aluminum_led_pcb_boards_1_layer.jpg

author: CatalinaWOW
author_rank: Super Contributor
timestamp: April 14, 2015, 11:33:34 pm
content: Don't forget to include the cost of electricity in your estimate of what it takes to plate these enormous boards. Lots of amp hours involved in moving those copper atoms around. Remember that the exponent on Avogadro's number is 23, while the exponent on a coulomb is only 17, and as I recall the chemistry it takes two electrons per atom.Lamination is the way to go, and that requires capitol investment. Your key is to find companies who do this lamination and move up the food chain. The kind of company you want will probably be doing some kind of continuous roller press. If your volume is high enough and your trace pattern simple enough you might even look into a roller stamp to cut the foil prior to lamination.Don't buy retail from the guys who deal in boards that are 0.01 sq meter when you want each piece an order of magnitude bigger, and want hundreds of pieces.

author: mrflux
author_rank: Contributor
timestamp: April 15, 2015, 07:04:46 am
content: @CatalinaWOW: Right. But the electricity consumption would be the same as for those who make the copper foil to begin with right?In the video shared by Alex Eisenhut (), it is mentioned that the copper foil is produced by making an electrolyte by dissolving copper wire, electro deposition onto a drum, which forms the sheets that are then cut. They could have more efficient machines etc., but the process is the same.I love the idea about roller stamping the foil. I'll look into that!

author: brutester
author_rank: Contributor
timestamp: April 15, 2015, 07:19:19 am
content: You can use screen printing on board. I've seen a smd project board done this way and it is working very good.I can send you a contact to a guy in Plovdiv that does it.

author: Alex Eisenhut
author_rank: Super Contributor
timestamp: April 15, 2015, 06:21:57 pm
content: Quote from: mrflux on April 15, 2015, 07:04:46 amNot necessarily, they might have a special industrial rate.

author: CatalinaWOW
author_rank: Super Contributor
timestamp: April 16, 2015, 01:41:50 am
content: You may be able to match their costs, but when you are comparing doing something in house to purchasing outside you have to add up all of your costs. You may be able to neglect something because it is a fixed expense (someone who has to be paid 8 hours a day for example, but is only working 5 or 6, or the capital costs of a machine which you have purchased for another project that is not fully utilized), but consumables like electricity always must be included. You should also include an opportunity cost. Is it better to apply your brain to learning how to duplicate something others have done, or inventing something new?The vendor of laminate may have other advantages (or disadvantages). They may be in a region with cheap hydro power, low labor rates, proximity to raw materials so transportation costs are low and so on.Unless you can identify some key advantage you have (free building space, zero value for your own time, local tax break, a customer preference for locally source materials or something), you are best focusing on your idea, as others have said.