I don't think there are any duties charged on an order under $20. Every country is different though. Customs doesn't normally open a package any more. They have xray equipment and sniffer dogs if there's anything suspicious but they normally go off comercial invoices here in Canada.
Maybe it will slip under the UK's HMRC radar...
Last time I purchased something overseas, it was from Protocase based in Canada (total value about $350) and was stung for an extra $50 for import duties which was something I hadn't budgeted for, so want to avoid wherever possible. But as this is quite a low value ($30), I guess it's not worth their hassle.
Last time I purchased something overseas, it was from Protocase based in Canada (total value about $350) and was stung for an extra $50 for import duties which was something I hadn't budgeted for, so want to avoid wherever possible. But as this is quite a low value ($30), I guess it's not worth their hassle.
Just wanted to mention that my rep at pcbway.com (someone named Lambo) just sent me an email saying was no longer with pcbway, but still offering PCB fabrication. Honestly I'd rather still work with the PCBWAY website and hope this isn't a sign of the company (which is probably small already) falling apart. My impression of this rep is that from day one, he was trying to lure my business away from PCBWAY, hoping I'd work with him directly, and the company may have just caught him in the act and fired him. But from recent messages here, I guess I can assume they are still in business and still filling orders as expected. I hope that's true... I have 4 boards undergoing final updates that I'm hoping to get get done at PCBWAYs usual good prices!
Hmm, well my PCBs have arrived.
I'm chuffed to bits with the quality (at least for my first attempt / newbie-who-doesn't-know-what-to-look-out-for).
Top side
Bottom side
Excuse the hair and dust - macro photos really do reveal warts 'n' all
I'm chuffed to bits with the quality (at least for my first attempt / newbie-who-doesn't-know-what-to-look-out-for).
Top side
Bottom side
Excuse the hair and dust - macro photos really do reveal warts 'n' all
Nice! One hopefully small thing, I'm assuming your copper pours are both for shielding and electrical connections. It appears that you have a number of pours that seem to be isolated from each other.
Holding that very first attempt at PWB layout in tangible form really gives you a feeling of accomplishment, doesn't it? Kind of like that very first kiss, or first . . . well, first time for other things. 😀 For me, the feeling is still there even after laying out at least a dozen PWB's.
There are several ways to deal with them before sending Gerbers off to the PWB fabricator:
These unconnected "islands" of poured copper are undesirable because you can't easily predict how they will affect overall circuit behavior. They MIGHT provide some shielding effect, but then again they might behave as antennas that give all kinds of electromagnetic crud access to your circuit. Or, they might provide coupling between parts of the circuit that are best kept isolated from each other.
There are several ways to deal with them before sending Gerbers off to the PWB fabricator:
- Some PWB layout programs allow you to delete them individually after pouring the copper fill.
- A strategically placed via may provide connectivity.
- Your program may allow you to specify a minimum size (units of area - sq inches, sq cm, etc) for copper pour areas.
- Slight adjustments to trace locations may prevent the creation of unconnected islands, or allow them to be connected.
- Your program may permit some control over how the copper pour areas are generated - in the "Options" or "Configuration" section, look for parameter names such as "Copper pour stroke width", "Copper pour smoothing factor", "Chord height", "Copper pour minimum separation", etc. Be careful with these - they might correct the problem of unconnected islands at the expense of more serious problems.
- You may be able to add "cutouts" within the copper pour area, to specify areas where the program won't attempt to pour copper.
Copper pours are OK - well should be! They are for different potentials, VDD and VSS. In fact, I have three voltage levels, as the ground is different to VSS because although the main output is running at 12V, the majority of the circuit operates at 5V. so I have a Zener in there giving me 5V from 12V 🙂
It all tested out OK on the breadboard, although there were no copper pours then! 😀
My only real concern, especially for safety, is the 230V AC side. There will be moderate power going through some of the mains with the relay, but I looked at some calculators for track width depending on copper density and even with my highest currents, temp shouldn't raise more than about 10-15 degrees C...
I'll assemble the low voltage DC side this weekend, and hopefully, it will work, then I'll do the AC afterwards.
Ooooh so exciting for my first time 😀
It all tested out OK on the breadboard, although there were no copper pours then! 😀
My only real concern, especially for safety, is the 230V AC side. There will be moderate power going through some of the mains with the relay, but I looked at some calculators for track width depending on copper density and even with my highest currents, temp shouldn't raise more than about 10-15 degrees C...
I'll assemble the low voltage DC side this weekend, and hopefully, it will work, then I'll do the AC afterwards.
Ooooh so exciting for my first time 😀
When dealing with mains voltages, safety requirements dictate copper-to-copper clearance (and possibly trace widths) significantly greater than the dimensions you get from calculations based on insulation breakdown (or dielectric withstanding voltage), leakage current, or conductor temperature rise.
You really should consult the regulatory or standards organizations that apply to your location - in the U.S., it is usually "Underwriters Labs" (UL). You may need to get some help understanding these, since they typically appear to be written in engineering terms but are actually written in a dialect of legalese. After you understand how the regulatory bureaucrats look at your design, you may or may not follow their requirements - as long as your design is only for your personal, private, use.
Going from my superannuated memory . . . . Several years ago I did a preliminary PWB layout for a line-powered consumer device. As I recall, copper-to-copper spacing on the mains-connected circuitry (switch, circuit breaker, EMI filter, power transformer, etc) had to be at least 1/8" (125 mils), and spacing from mains-connected circuitry to ANY conductive material that a user may contact (chassis, mounting hardware - as well as the low-voltage circuitry) had to be twice that distance unless the separation included an air gap (i.e., slot in the PWB). I think the customer imposed these requirements, so they may not precisely reflect regulatory requirements of that time.
Dale
Hi
Getting the cheapest is one thing, I also want to know how well the pcb stands up to rework. I worked with a lot of US made pcb, they usually can stand up to desolder components a few times before the pads fell off. I ordered a run from China, visually, they looked good. BUT it won't stand up to desoldering. When I use solder wig to suck out the solder in the through holes, there is a chance that the pad will come out. So you really have one chance of making the board.
For production, it's ok. But for DIY and you want to experiment with different values. You are screwed with this!!!
I read good things about PCBway.com, how is their quality in turns of desoldering? What other company in China that make good pcb that can stand up to at least two or three desoldering?
Getting the cheapest is one thing, I also want to know how well the pcb stands up to rework. I worked with a lot of US made pcb, they usually can stand up to desolder components a few times before the pads fell off. I ordered a run from China, visually, they looked good. BUT it won't stand up to desoldering. When I use solder wig to suck out the solder in the through holes, there is a chance that the pad will come out. So you really have one chance of making the board.
For production, it's ok. But for DIY and you want to experiment with different values. You are screwed with this!!!
I read good things about PCBway.com, how is their quality in turns of desoldering? What other company in China that make good pcb that can stand up to at least two or three desoldering?
That has more to do with board design. It's easier to rework a board that has slightly larger through holes. larger pad sizes and thermal reliefs make soldering easier as well. I've had no issues with reworking yet.
No, I have standard library, I use the same 52mil pads 31 drill for 1/4 resistor all these years. Never did I have problems with US made pcb all these years until you get to the 4th or 5th desoldering. I would say 30% of the pads came off on the first desoldering with the run of China boards.
I have been in the field for 30 years, doing a lot of soldering and rework, not a novice that messing up on soldering. So technique is not in question here.
Yes, I increase the pad size if all possible. On the tight layout, Now I use 60mil pad and increase drill size to 35 to make extraction easier. I tried 70mil, but it made layout harder because it cut up the ground and power plane in tight layout.
Even in US made boards, some can stand up to rework a lot better. I had boards that never failed. But all of them can take at least 4 to 5 desoldering.
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These days I doubt it matters who etches it. They likely all use the same Chinese 1/16" 1 oz FR4 board unless you specify something else. As I said, I've had no issues with reworking.
Not true, at work 9 years ago, we never use 1oz copper. We did very fine pitch surface mount stuffs. We use 1/2oz or 1/4oz. We used local companies for fast turn. It's been a few years, back in the days, we did 0402 resistors and caps, TSSOP ICs, BGAs that were fine pitch. I don't know whether companies in China can even touch that. Rework was just a norm. Never have we encounter any problem.
You think 52mil pads and 31 drill is small, try 0402 SM pads with no through holes!!! China boards from the company I order will never survive even one rework. That's the reason I want to look a little deeper.
You think 52mil pads and 31 drill is small, try 0402 SM pads with no through holes!!! China boards from the company I order will never survive even one rework. That's the reason I want to look a little deeper.
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1 oz 1/16" board is the default at any online board house that I've looked at but there are many other options available at every one of them.
People hand etch SMT with toner transfer. Photo resist works well too. I used 1/2 ounce for that as well. It isn't anything out of the ordinary these days. 35 mil pads aren't uncommon if you want to squeeze traces between IC pins. Up until a few months ago I hand etched everything.
I can have 10 Chinese boards produced cheaper than 2 North American boards and they are usually delivered to my door within a week of ordering. Build a prototype. I torture test it,rework it and figure out what components are going to work, then throw it on a shelf somewhere and assemble some finished products without all the damage from rework. You get a nicer finished product that way.
I have to agree with you on this. Usually by that point I would have realized I screwed up the design and started with corrected boards.
I can comment on that. Thanks to an occasional screw up by me in my layout, etc. I have had to do some "rework" on boards that I ordered from PCBway. I never experienced any problems like pad lifting, etc. even with stubborn leads that were difficult to remove and required some aggressive heating and pulling.
Wrong, If you work on RF boards, you change it many times. You cannot just design on paper, you fab the run of boards, then you tweak. You design guitar effect and amp, every little change in value of components change the sound drastically. You experiment to get the sound.
In real world, it's not people's design that screwed up. Most likely marketing change their mind, or different requirements come up, engineer need to accommodate the changes and has to rework the board. Rework over and over is a necessary evil. It's not like there is simple goal here.
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Dale, thanks for that. I did read about UL and it was a bit complex to understand. My friends in the field suggested I should have a 1.3mm gap, but with the soldermask, and relatively warm temps, it should be OK.
I've already reworked the design for a v2 increasing the insulation width and fixing an error in my design where I ended up mixing my different voltage levels. Stupid mistake in carrying the design into the computer - was fine on the breadboard!
I've already reworked the design for a v2 increasing the insulation width and fixing an error in my design where I ended up mixing my different voltage levels. Stupid mistake in carrying the design into the computer - was fine on the breadboard!
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