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EEVblog => EEVblog Specific => Topic started by: Psi on January 31, 2012, 12:12:36 pm

Title: EEVblog #241 - Circuit Labs PCBs from New Zealand
Post by: Psi on January 31, 2012, 12:12:36 pm
Nice comparison between the two boards.
Especially the closeup stuff.

The silver plating also looks really nice.

For the new uCurrents you could get the front panel text done as silver plated copper instead of using the silkscreen. It might look quite nice.
 Just an idea. :)


EDIT: reading some of the youtube comments for the video, someone said that silver coatings can tarnish, so it may not be the best plan.
Title: Re: EEVblog #241 - Circuit Labs PCBs from New Zealand
Post by: EEVblog on January 31, 2012, 12:28:47 pm
Yes, silver is notorious for tarnishing. Great when new, no so great when left for a long period.
Some cheap-arse gold plating can be pretty poor too, but not nearly as bad as silver.

Dave.
Title: Re: EEVblog #241 - Circuit Labs PCBs from New Zealand
Post by: Rufus on January 31, 2012, 12:44:22 pm
Yes, silver is notorious for tarnishing. Great when new, no so great when left for a long period.

Silver tarnishes within days exposed to atmosphere, they need to be delivered in vacuum sealed packs.

Spraying them with the rosin based flux you can get in aerosols will protect them but the boards stay tacky and are more likely to need washing after assembly.

Edit after watching the video:

You generally don't want silver plating because of the tarnishing problem. A pad with solder finish is always going to solder easier than one with silver. The problem with hot air solder leveled (HASL) is poor control of how much solder is left on the pads and that really is a problem for fine pitch SMT parts where solder on the pad reduces the amount of paste (and importantly flux) that gets stenciled on to it, it also prevents parts sitting flat on the PCB. Gold of course is the expensive answer the other down side being risk of embittlement so some people think silver is the safer option for difficult parts like QFNs.

On the silk screening the difference looks to be the NZ ones were not screened but photo imaged - cost again. Same might apply to solder resist differences.

On the high cost of panels - they don't fit into the prototype flows which give the cheap prices. When you buy 50 boards on a prototype flow they put one of your boards on a big panel along with one of everyone elses boards and make 50 of those big panels. You share the set up costs with everyone else on the big panel and get the volume savings making 50 of the same. When you buy 50 boards in panels of 10 it is harder to fit your larger panel in with other boards and they would only need yours on 5 big panels not 50. The cheap prototype flows are all about using all the space on a large panel and making as many of the same large panel as possible. That is why you get big discounts for longer turn around, it gives them more opportunity to fit your boards in with others.

It is difficult to calculate true costs for these flows, I have had automated quotes like it was cheaper to buy 10 boards and throw two away than it was to buy 8. 
Title: Re: EEVblog #241 - Circuit Labs PCBs from New Zealand
Post by: Psi on January 31, 2012, 01:12:40 pm
I've used gold before (from pcbcart) and those boards still look perfect today (a year later)
I guess they use proper gold plating.
Title: Re: EEVblog #241 - Circuit Labs PCBs from New Zealand
Post by: electrode on February 01, 2012, 12:13:33 am
Wow PCBZone do nice work. So we know what it cost you to get 4 boards, but could someone please tell me what the pricing structure is? $x/sq in. + setup fee? Or are there minimum sizes/quantities and so forth?
Title: Re: EEVblog #241 - Circuit Labs PCBs from New Zealand
Post by: mikeselectricstuff on February 01, 2012, 12:29:16 am

Silver tarnishes within days exposed to atmosphere, they need to be delivered in vacuum sealed packs.

Spraying them with the rosin based flux you can get in aerosols will protect them but the boards stay tacky and are more likely to need washing after assembly.
Liquid fluxes as used in flux pens dry to a non-sticky finish, and will keep a silver board good for ages.

Silver is absolutely fine if you are assembling PCBs within a week or two, and always preferable to HASL for SMD boards for the reasons mentioned above
 
For boards to be hand assembled, gold has the advantage of the colour change when soldered making it easier to spot joints you've missed, or had insufficient paste.
Title: Re: EEVblog #241 - Circuit Labs PCBs from New Zealand
Post by: EEVblog on February 01, 2012, 12:31:49 am
Wow PCBZone do nice work. So we know what it cost you to get 4 boards, but could someone please tell me what the pricing structure is? $x/sq in. + setup fee? Or are there minimum sizes/quantities and so forth?

They have an online instant quote system, but you currently have to register to use it.
They are thinking about removing that restriction.
There is no setup fee for prototype boards.

Dave.
Title: Re: EEVblog #241 - Circuit Labs PCBs from New Zealand
Post by: electrode on February 01, 2012, 12:35:31 am
Thanks, saw that before, but didn't really want to register if there was a quick answer. I usually just perma-ignore sites that force registration for basic info. :p
Title: Re: EEVblog #241 - Circuit Labs PCBs from New Zealand
Post by: BravoV on February 01, 2012, 12:42:36 am
Really interested at the pcbzone's delivery time in just few days, is that the standard delivery time even just for few proto boards ?
Title: Re: EEVblog #241 - Circuit Labs PCBs from New Zealand
Post by: McMonster on February 01, 2012, 12:58:35 am
Really interested at the pcbzone's delivery time in just few days, is that the standard delivery time even for just a few proto boards ?

The small problem with Dave's service reviews is that any hobby electronics related business that cares about whatever they're doing would likely prioritize any order labeled "for Dave Jones". Makerbot is the extreme example of this phenomenon as they've sent Dave a box full of awesome without even asking. ;)
Title: Re: EEVblog #241 - Circuit Labs PCBs from New Zealand
Post by: EEVblog on February 01, 2012, 03:01:54 am
Really interested at the pcbzone's delivery time in just few days, is that the standard delivery time even for just a few proto boards ?

The small problem with Dave's service reviews is that any hobby electronics related business that cares about whatever they're doing would likely prioritize any order labeled "for Dave Jones". Makerbot is the extreme example of this phenomenon as they've sent Dave a box full of awesome without even asking. ;)

Yes, PCBzone knew this one was for me (and it was a sample, I didn't pay for it), so I'm not sure if they rushed my job to impress me, or just because they happen to have idle capacity at the moment, or they really are that quick all the time. it's always going to vary based on how many jobs they have on though.
For the prototype service they publicly quote 3-6 days. To me, that means, expect 3 days usually, but if we are busy, it may take 6.
I've generally found that PCB houses don't sit on jobs, if they have the capacity available at that time, they push it through at the first available opportunity.
PCBcart used to be easily able to meet their 8 day quoted time a few years back. But then they got so massively popular that they started to almost always be late.

Best service ever was Agilent who had a replacement scope hand delivered to my door within 12 hours of the review unit failing :->

Dave.
Title: Re: EEVblog #241 - Circuit Labs PCBs from New Zealand
Post by: Psi on February 01, 2012, 04:06:41 am
I quite often order stuff from digikey on Friday, even as late as midnight.
I always find an email waiting Saturday morning saying the package has shipped and 90% of the time the package arrives Monday morning.
That's pretty fast service, and it's almost always quicker than ordering during the week.
Title: Re: EEVblog #241 - Circuit Labs PCBs from New Zealand
Post by: Bored@Work on February 01, 2012, 07:52:44 am
prioritize any order labeled "for Dave Jones"

Business idea: Print authentic "for Dave Jones" stickers and generate authentic "for Dave Jones" electronic certificates , sell them for a nominal fee, so people could stick them onto their orders in the hope it speeds up things  ;)
Title: Re: EEVblog #241 - Circuit Labs PCBs from New Zealand
Post by: Rutger on February 02, 2012, 07:01:39 am
Any recommendations on PCB prototyping service here is the USA?

Rutger
Title: Re: EEVblog #241 - Circuit Labs PCBs from New Zealand
Post by: electrode on February 02, 2012, 07:04:46 am
Dorkbot (http://dorkbotpdx.org/wiki/pcb_order) is the cheapest I've found @ $5/sqin (3 copies) and free US shipping. They also look to do gold plating as standard, as well as the sexy purple soldermask. I put an order through today with a simple board to see how it goes.
Title: Re: EEVblog #241 - Circuit Labs PCBs from New Zealand
Post by: mobbarley on February 02, 2012, 07:11:09 am
prioritize any order labeled "for Dave Jones"

Business idea: Print authentic "for Dave Jones" stickers and generate authentic "for Dave Jones" electronic certificates , sell them for a nominal fee, so people could stick them onto their orders in the hope it speeds up things  ;)

I live in sydney, i'll just have to start ordering under my other name - dave jones.
Title: Re: EEVblog #241 - Circuit Labs PCBs from New Zealand
Post by: Rutger on February 02, 2012, 02:09:25 pm
Dorkbot (http://dorkbotpdx.org/wiki/pcb_order) is the cheapest I've found @ $5/sqin (3 copies) and free US shipping. They also look to do gold plating as standard, as well as the sexy purple soldermask. I put an order through today with a simple board to see how it goes.

Thanks,  let me know what you think of the quality when you get he boards back from them.

Rutger
Title: Re: EEVblog #241 - Circuit Labs PCBs from New Zealand
Post by: Frenchie on February 02, 2012, 04:13:43 pm
I've ordered from dorkbot (Laen) a couple of times. The boards have been consistently good quality and the turnaround time is excellent. The last order I placed I had in my hands in Australia 16 days later.

Internal cutouts also don't seem to be a problem (despite not being promised). Considering they make big panels that all have to be routed out anyway I don't see that it would suddenly become an issue.

The only issue I have is that $5/sq inch adds up very quickly. If I'm going to do a small board they're my first choice every time. If it's a bit bigger then I might look to go somewhere like Itead where I can get it done a bit cheaper for lower quality.
Title: Re: EEVblog #241 - Circuit Labs PCBs from New Zealand
Post by: G7PSK on February 02, 2012, 06:31:50 pm
Hi Dave I was wondering how much extra cost gold plating is as opposed to silver or is there another reason for going to silver.
I have had very little experience of board design or etching I tried it in the 70's but have not done any since and I am now just getting back into such things. I love your shows and have been pushing my internet to the limits ever since i discovered your site.
 
Title: Re: EEVblog #241 - Circuit Labs PCBs from New Zealand
Post by: Alex on February 02, 2012, 11:59:09 pm
In the video the itead service is compared with pcbzone, also in terms of cost.

I did a cost comparison between the two for a standard 10x10cm board, 2 layers, green soldermask and 1.6mm thickness, 1oz copper.

For itead there is a standard product, you get 10x PCBs of the above for the total price of USD 28.00 (ignore the February sale). A cost of USD 2.8 per board, plus shipping.
http://iteadstudio.com/store/index.php?main_page=product_info&cPath=19_20&products_id=175 (http://iteadstudio.com/store/index.php?main_page=product_info&cPath=19_20&products_id=175)

I then used the members' calculator in pcbzone. For the same board to get 10x PCBs from pcbzone, I get a quote of NZD 712.50 (USD 592). A cost of USB 59 per board, plus shipping and handling.

http://desmond.imageshack.us/Himg209/scaled.php?server=209&filename=64420792.jpg&res=medium (http://desmond.imageshack.us/Himg209/scaled.php?server=209&filename=64420792.jpg&res=medium)

And even though it is no longer a direct commparison, I decided to also try ordering 5x as suggested in the guidelines of the pcbzone service. The cost now came to NZD 337.5 (USD 280) i.e. USD 56 per board.

http://desmond.imageshack.us/Himg252/scaled.php?server=252&filename=96448079.jpg&res=medium (http://desmond.imageshack.us/Himg252/scaled.php?server=252&filename=96448079.jpg&res=medium)

The quote from pcbzone is not different from any traditional professional house, e.g. Eurocircuits - if anything they are more expensive.

And another point is about a limitation pcbzone applies, which is to only have silk on top. I am not sure what itead states on this, but the boards I have in front of me from itead have silk on both sides.

Am I entering the wrong information or otherwise missing something here? Because quite frankly, what is the excitement about?
Title: Re: EEVblog #241 - Circuit Labs PCBs from New Zealand
Post by: EEVblog on February 03, 2012, 12:02:16 am
Hi Dave I was wondering how much extra cost gold plating is as opposed to silver or is there another reason for going to silver.
I have had very little experience of board design or etching I tried it in the 70's but have not done any since and I am now just getting back into such things. I love your shows and have been pushing my internet to the limits ever since i discovered your site.

Gold usually isn't much extra, and very worthwhile getting. I don't know how much more Circuit Labs charge though.
I got silver because that's what Circuit Lab's standard offering is.

Dave.
Title: Re: EEVblog #241 - Circuit Labs PCBs from New Zealand
Post by: G7PSK on February 03, 2012, 09:37:06 am
Thaks for the answer Dave, When I first left school (1969) I trained as a horologist (Watchmaker) back then gold plating was far cheaper than silver to apply as the gold could be so much thinner than silver or other plating very often being applied through vapor deposition so thinly that you could see through it with a loupe and a strong light.
Title: Re: EEVblog #241 - Circuit Labs PCBs from New Zealand
Post by: janekm on February 03, 2012, 10:20:18 am
Thaks for the answer Dave, When I first left school (1969) I trained as a horologist (Watchmaker) back then gold plating was far cheaper than silver to apply as the gold could be so much thinner than silver or other plating very often being applied through vapor deposition so thinly that you could see through it with a loupe and a strong light.

I think the difference is that the "Silver" finish on PCBs is a chemical finish done by immersion, not vapor deposition, so it fits in well with typical PCB fabrication flows. My guess would be that the main extra cost with "gold" finish (ENIG, electroless nickel immersion gold) is the extra processing step for the Nickel that is under the gold.

For the Chinese boardhouses the extra cost seems to be the same (or close enough) for ENIG or Silver, but I know of at least two European boardhouses that have switched to the Silver finish as standard (partially due to the Rohs requirements, HASL Rohs being more trouble during assembly, partially due to the higher prevalence of QFN and BGA packages requiring flat surface finishes).
Title: Re: EEVblog #241 - Circuit Labs PCBs from New Zealand
Post by: mikeselectricstuff on February 03, 2012, 10:46:42 am
According to a guy at a local PCB place, an issue with electroless gold is that the process needs extensive treatment of waste water due to the chemicals used, which is why some smaller PCB houses either don't do it or outsource it.
Apparently the chemistry is also much more critical than other finishes, so again unless they are doing a lot of boards it may not be worth the investment in equipment and staff.
Title: Re: EEVblog #241 - Circuit Labs PCBs from New Zealand
Post by: janekm on February 03, 2012, 01:17:01 pm
According to a guy at a local PCB place, an issue with electroless gold is that the process needs extensive treatment of waste water due to the chemicals used, which is why some smaller PCB houses either don't do it or outsource it.
Apparently the chemistry is also much more critical than other finishes, so again unless they are doing a lot of boards it may not be worth the investment in equipment and staff.

I was just reading this document which discusses the impact of the different finishes, with comments from board houses and assemblers: http://www.epa.gov/dfe/pubs/pwb/pdf/sf_guide.pdf (http://www.epa.gov/dfe/pubs/pwb/pdf/sf_guide.pdf)

It also mentions some of those issues, especially with regard to the chemistry.
Title: Re: EEVblog #241 - Circuit Labs PCBs from New Zealand
Post by: chrisc on October 01, 2012, 08:21:54 am
The small problem with Dave's service reviews is that any hobby electronics related business that cares about whatever they're doing would likely prioritize any order labeled "for Dave Jones". Makerbot is the extreme example of this phenomenon as they've sent Dave a box full of awesome without even asking. ;)

I know this thread is many months old, but I thought I'd add a comment for the reference of anyone who comes across it in the future.

I sent a order to PCBZone last week because I liked what I saw in Dave's review, but didn't mention anything about EEVblog so they didn't know who I was or where I'd heard of them. The order was processed on Tuesday and shipped on Thursday, which as far as I'm concerned is pretty good going. I'm very pleased with the boards, too.
Title: Re: EEVblog #241 - Circuit Labs PCBs from New Zealand
Post by: Psi on October 01, 2012, 08:36:35 am
According to a guy at a local PCB place, an issue with electroless gold is that the process needs extensive treatment of waste water due to the chemicals used

Well that explains it, in china they probably don't treat the water at all, so little cost difference   :(
Title: Re: EEVblog #241 - Circuit Labs PCBs from New Zealand
Post by: SeanB on October 01, 2012, 03:56:06 pm
They treat to recover the gold, and the rest is down the drain out of sight...............