Dear all, I'm trying to get a set of equipment for my lab using which we can prototype PCBs. The cost is not important and I can go as high as $100k. However, I want something that is very reliable. I have used laser prototyping equipment (from LPKF) and mechanical ones (also from LPKF) for many years and both methods are very unreliable. When they work, life is amazing but most of the time they give issues.
Now, I'm considering prototyping using the following two approaches. Either wet etching approach (spin-coating, UV, developing, etching) or dry etching approach (a very high-end high-resolution laser-LED printer, dry-film laminator using heated bed, UV, etching). Can you guys please share your experience with any of these methods? I'm inclining towards dry etching method since the wet etching is messy and requires high maintenance. But also if you have any other approaches in mind I would love to hear. Thanks in advance.
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I don't know but there are companies that specialize in it. I'm pretty sure chemical etching is still the standard method.
There are ways for hobbyists to do it but most electronics companies farm it out and there companies that specialize in fabrication for hobbyists or prototyping.
I've had a couple boards made by Seed Studio/Fusion and I got 10 or 20 small boards for less than $100 total, including DHL shipping (before the current tariff situation). They are made in China. It took about 10-14 days. They were double-sided boards with silkscreen & solder mask, etc. More "professional" than I could have done myself.
Wet etching requires a room to keep the splashes to a minimum.
That was how we used to do it in the late 1960s, forget it. Been there and got the spotted tee-shirt.
How about using a CNC to cut the design from normal copper clad laminate?
Example shown here:-
Of course use a bigger CNC machine for bigger PCBs.
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How are you going to handle plated through holes ?
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Ammonium Persulphate Copper Etchant is less messy than Ferric Chloride but a bit more fussy to use.
To be honest, unless you absolutely need to etch boards at home, I would suggest one of the online board houses. I've used JLCPCB for a while now - in fact I've just sent off 5 4-layer designs for my RC2014/RCBus Motorola M68000 boards today.
P.S.
One reason for doing it yourself might be speed. But the 1st time it will take you longer to set-up & learn than ordering the boards.
If you live in a city with a board fabrication house you can probably get 1-day turn-around which is probably still slower than you can do at home once you're set-up.
The forum member @liuzengqiang seems to be running a one-stop shop which includes board assembly and maybe board production (based on some of his older threads e.g. Dip soldering boards causing relay stress). He may have something to say about what is required to get started.
What type of components are you intending to use? All leaded components? If so, then like in the 1960's all will work. But if you are using SMT, surface mount devices, then you begin to have problems with using fine pitch devices. Also when the board it not already tinned, you will have trouble soldering reliably.
@6v6gt Thanks for the mention! Yes, I have a one-stop-shop for design--firmware-fab-support type of consulting gig. My fab work starts with already printed circuit board, from overseas board houses. I do the assembly, testing, fixing, firmware loading and function testing in-house. Making printed circuit board has not been a part of my expertise though.
I'm just thinking, If the OP has extensive experience with in-house board fabrication and a 100 grand budget for a really good desktop fab system, there must be some reasons of not using board houses near and far that we don't know about. Based on just simple assumptions of prototyping work, board houses seem very reasonable. If fabricating boards are the ONLY requirements, what about stencils, pick-n-place, reflow? Where does this $100,000 investment end?
With a $100K expense, comes necessary human resources. You need a large part if not a whole person to maintain the equipment so every other board is not like the first board that took forever and numerous trials to get right. I speak from my own experience running a desktop pick-n-place machine.
I don't know the standard in-house prototype solution of coating a routed copper clad with tin. I think in a board house they use hot air solder leveling or HASL. That's a lot of solder in a bath to dip into and remove excess. Without tin coating, the copper clad gets tarnished easily and attracts finger prints. It's just generally hard to solder.
FYI - Where I work (and where I have worked) "fab" relates to the bare board. In fact, I've often heard the bare board called the "fab". I call them "bare boards" but someone might say, "We can't start production until we get the fabs." When it's soldered and done we call it a "PCB assembly" or "PCBA".
And everywhere I've worked the bare board fabrication has been done by an outside PCB fabrication house. It's a different specialty.
Where I work now we do the PCB assembly (surface mount and through-hole wave soldering, etc.).
I've worked at other places where we'd order the bare boards and other components and then send a "kit" to the assembly house.
The company that I used to work for went from ferric chloride etching to using an LPKF PCB milling machine over 20 years ago, and never looked back.
We found that we had to limit the number of users to a few 'specialists', otherwise people would change the settings and it was difficult to know what they had done.
Are you using the inspection microscope to verify that the cutter is cutting to the right depth?
This is quite likely to be well out of the range of experience of most of the people here. And $100k, plus the recurring costs of anything that elaborate, will buy a lot of quick-turn professional board house PCBs, even at non-China fabs.
I have an old LPKF machine (mechanical), and I've pretty much given it up in favor of OSHPark and China. For the boards I was making, I never found it particularly "unreliable", but it went quickly from very simple boards to "unsuitable" due to lack of fine-pitch capability and plated holes.
Yes I've used JLCPCB too and have been very happy with the results. Amazingly inexpensive and boards come back in less than a week. They're at my door step in less than 7 days from when I send them the files. And they cost only $4 for 5 boards plus about $20 for shipping. (trump's tariffs may have changed that though)
I also have been using JLCPCB for a number of years. They provide PCB fab consistently and timely enough for me. Unless there's a compelling reason to maintain an in-house expertise in PCB fab at the prototyping quantity, they are hard to beat.
The same way as you handle holes in a Ferric Chloride etch. Which is basically:-
- You don't use them and stick to single sided designs only, or
- By designing in tinned copper wire links to the other side that mimic the effect of a plated through hole. If your CNC is such that you can align it accurately enough to create a double sided board.
Use JLCPCB , they can build and test the boards too and carry vast stock of parts .
So paying silly money for a system with health safety and maintenance issues is just not worth it .
JLC can do multi layer boards, gold connectors, different colours , stencils, different shapes, holes etc etc and 24hr is you need.
If you use easy ADA you can even check stock and reserve parts
Really is a no brainier
There are systems available where you can rivet a through hole.
I'm still wondering what sort of development needs fast turn around on PCBs, especially when you have to compromise on design rules, which surely means you need a different design for production, in which case what exactly are you testing.
In the companies I have worked at, we spend a lot of time at the design stage simulating and possibly prototyping small parts of the circuit before committing to a v1 pre-production board. That board is then used as a vehicle for all manner of testing, and the design is refined for a v2 production ready PCB.
I can see there might be a desire for "agile" hardware development which involves a lot of hardware iterations, but bringing PCB fabbing in-house seems like a retrograde step compared to advanced simulation techniques.
Hi,
I use JLCPCB and at my work.
Major advantage.
Fast, to Australia.
You don't have to have dedicated floor space for equipment and environmental safeguards.
You don't have the maintenance needed to support the equipment.
You don't have the cost of chemical storage, safety, and waste removal.
You don't have to have trained staff to accomplish all this.
My work place is small and China pcb manufacturers have been a god send to enable us to produce customised and prototype products.
If you are still looking at in house production, go and talk to the expert/suppliers of the PCB systems.
Tom.... 
