Assembly line thoughts - DDM Novastar - Page 1
Forum section: electronics / general

author: kylehunter
author_rank: Regular Contributor
timestamp: April 06, 2019, 02:19:04 am
content: Hello all,My company does electronics design and prototyping of consumer products. Recently, however, a few clients who are more in the industrial space have been wanting us to support them with small production runs. This makes sense for them, as us being in the US, and the ones who designed the PCB and firmware allow it to be entirely in-house.Our requirements:Up to 500 boards a month, around 100 components each boardMostly leadedSmallest components are 0402, no BGA, QFN-pitch of 0.4mmPrefer new, as I don't want the headache of worrying about used issuesBudget around $60kI have completed hours upon hours of research, and people are strongly opinionated about this topic. I have contacted DDM Novastar and talked with them extensively. I have never encountered such incredible pre-sales customer support in my life.I received a reference sheet of around 15 companies that are using their GF-12HT oven. I called them, and they all seem very satisfied, with the only complaint being that the edge 0.5" of the board is tough to reflow. Novastar themselves told me about this "issue" beforehand.It seems that the GF-12HT would be able to do significantly more than my 500 boards a month, so that would not be the bottleneck.For the P&P, the LE-40V should have around 3-4x the capacity I need and can do the 0402 and 0.4mm pitch QFNs. Both of these bring me to around $40k, which gives me some room for a stencil printer and feeders.My question(s)/concerns are as follows:People online, specifically SMTNet, who haven't owned a Novastar, talk down on Novastar, treat them like they are garbage, and act like going used is sooo much better.Of course they can't compare to heller/fuji/etc, but we don't need 1000's of perfect boards a day.The people I have talked to who have owned their equipment seem very happy.Does this sound like my plan is valid? We are a tiny company. This would be the largest investment we have made. We really can't absorb a loss here.Any other suggestions/advice/etc.Thank you so much for any help,Kyle

author: coppercone2
author_rank: Super Contributor
timestamp: April 06, 2019, 10:30:23 am
content: with modern PCB manufacturing I think testing is going to be your most likely bottleneck. All that other stuff flies (especially SMD) in comparison to any human work.Did you factor in testing jigs and testing personnel and testing procedure development? as for a potential loss, a PCB tester breaks down in your office and you are up shit creek because of a production delay. Especially if no one knows how to fix it.You would probably want to do an analysis of operations after some time to see if you can identify a bottleneck you did not anticipate.And inspection. You don't want to make it so your making boards for a long time without inspections because then you might produce a bunch of garbage, you want sampling and feedback continuously to identify and process problems that need tuning. This inspection is time consuming.

author: spongle
author_rank: Regular Contributor
timestamp: April 06, 2019, 11:20:42 am
content: With you having no experience as a manufacturer, only one client, and this investment being an existential threat to your business, seems like a very bad idea.I can see you're trying to do your due diligence, but there are likely many many factors you don't even know to research (e.g. last poster's point about inspection).very hard to see how this could make economic sense compared to a specialized fab house.maybe you can position yourself as a service provider, outsource the manufacture to someone else local or overseas, and provide coordination, final testing, firmware programming etc.

author: kylehunter
author_rank: Regular Contributor
timestamp: April 06, 2019, 11:44:47 am
content: Quote from: coppercone2 on April 06, 2019, 10:30:23 amVery good points. As for now I have planned on doing manual testing, as with only seeing up to 500 boards a month, that is not too overwhelming to handle. Yes, definitely have been planning on the added manpower for this.Many of the boards at the start will be unique LED panels, which are quite easy to test. The others are LCD based driver boards, again pretty easy to test.Do you have any good resources on more automated testing jigs and setups in the future? My plans have been just to design a pcb with spring contacts that would mate with the main board and could interface with it.Quote from: spongle on April 06, 2019, 10:30:23 amGlad you bring that up, that has definitely been the main decision I have been having to weigh. Not to get too into the business side of things, but the only reason I mentioned the one client, is because that is the main one we are working with. We also have another two that we would be able to quickly support. The way I am viewing it, we have three client's who we have dealt with for years who can help up with the initial orders to get us going and support the running costs of the equipment.Once everything is setup and we have a good setup, then will be branching out. We have a pretty well developed client base, with many who focus on small high quality boards, which we can handle.EDIT:My goal is to make turnkey small scale prototype and production runs a portion of our business. This initial client base just allow us to do so with much less risk, assuming the equipment is reliable.I was mostly being overdramatic about the cost significance. No, a failure won't sink us, yes it would make it very difficult to branch down this road again.Thank you both very much

author: OwO
author_rank: Super Contributor
timestamp: April 06, 2019, 01:42:24 pm
content: Unless you are a fairly big company (>50 engineering staff) it rarely makes sense to do PCBA in house. Even just running the pick and place machine is hugely complex and there are 1000s of things that can go wrong. I highly recommend reading all the threads here about people setting up a PnP system for the first time. You are going to need in-house expertise for this and any average EE isn't going to cut it.

author: OwO
author_rank: Super Contributor
timestamp: April 06, 2019, 01:46:23 pm
content: https://www.eevblog.com/forum/manufacture/the-reality-of-a-pick-and-place-lifestyle/

author: Reckless
author_rank: Frequent Contributor
timestamp: April 06, 2019, 03:18:01 pm
content: Kyle,You and I spoke over the phone 2 weeks ago. I still don't think APS Novastar makes good machines. I have owned 2 of their ovens and 1 of their wave solder machines. Their ovens are defintely better than China, they are pretty BUT NOT usable for more than basic prototyping (less than ~1000 boards). There is a reason why most of the used ones have very little use. Same goes for their pick n place machine. I wouldn't touch theirs with a yard stick. They are not even on the list of pick place machines. Their technology is even below china. IMO, Chinese pick n place machine are much more desirable. I bet they are reselling an old chinese pick n place from 5+ years ago. I would be surprised if anyone succesfully used their machine to make 500 boards. Likewise would be impressed if someone was able to use their reflow oven 10,000 times.I would buy oven used, stencil printer used and invest heavily in new feeders and good pick place machine. I'm a big universal instruments pick n place fan but they are big machines but super precise and repeatable esp for 0402. You can find them cheap and universal will support them for $500. One major cost you are overlooking is setup/training. I spent more on this then everything else. Next major cost was feeders which typically run more than the machine.For quantities less than 1000/month I wouldnt want to do it in house. You are better off partnering with an EMS and not getting your hands dirty. I understand being passionate about SMT as a hobby but strictly business wise not a wise investment. No such thing as reliable table top SMT. The closest thing is the Essemtec fox which had issues running at speed when I saw it demonstrated.

author: jmelson
author_rank: Super Contributor
timestamp: April 07, 2019, 02:56:28 am
content: The only bad thing you mention is the 1/2" border. This is pretty serious. I can imagine maybe 1/2" border on two sides, but if it needs a 1/2" border on all FOUR sides, this would be a REAL problem. I often do boards with parts just 5mm from several edges, and have no problem placing or reflowing them. So, you might want to reconsider this. Of course, look at your existing boards, maybe this is actually NOT a problem for your designs.Jon

author: kylehunter
author_rank: Regular Contributor
timestamp: April 07, 2019, 03:09:47 am
content: Quote from: jmelson on April 07, 2019, 02:56:28 amNo, I meant 1/2" from the edge of the conveyor. So it's a 12" wide conveyor, if you reflowed a 11" wide board the edges may not reflow.

author: jmelson
author_rank: Super Contributor
timestamp: April 07, 2019, 04:42:56 pm
content: Quote from: kylehunter on April 07, 2019, 03:09:47 amOh, of course, I suspect all machines are like that. Well, if you never will make a board over 11" in the NARROWER dimension, then it will be fine.Jon

author: kylehunter
author_rank: Regular Contributor
timestamp: April 11, 2019, 02:12:45 am
content: So after listening to many people's options and thoughts, I have decided against novastar. There is a reseller near my office that offers full support, training, and service on used equipment. They also fully refurbish all equipment beforehand.Oven would be a Heller 1500. P&P would be a Juki 2060 or an assembleonTopazOpal Xii. The assembleon would be 10k-15k less than the Juki.What are your thoughts with this route, and the Juki vs Assembleon?As for the feasibility in-house, I have a commitment now from a second existing client we do design work for, to do the assembly. Both of the clients together easily make the machines feel comfortable financially.Thanks!EDIT:It is an assembleon Opal Xii, not a Topaz

author: Reckless
author_rank: Frequent Contributor
timestamp: April 11, 2019, 05:48:23 am
content: 1500 is kind of old and may not be lead free capable. How much is he selling it for? I have a brand new in crate 1707EXL for $15k which is atleast 10+ years newer and won't need any maintenance/repairs for a loong time. Plus Hellers are much easier to learn on, very intuitive. 1707 uses Windows XP.Topaz is good, I heard bad things about the Juki 2030/2040/2050/2060 series from Joe. I had bad luck with older Juki's. I have an Assembleon Sapphire (which is same as 2 Topaz's put together) for sale $10k (with tons and tons of brand new spare parts) in great condition.$25k gives a quick ROI.

author: Styno
author_rank: Regular Contributor
timestamp: April 11, 2019, 11:11:33 am
content: Topaz maximum component height is only 6.5mm. Also the spec says it will handle 0402 and up, but I'm always weary of actually using the smallest possible chip size capability. I haven't tried it but our Dima Optimat should also be capable of 0402, however I strongly suspect that one would need luck, lots of twiddling to get everything right and a very hands-on approach to production.

author: mrpackethead
author_rank: Super Contributor
timestamp: April 11, 2019, 11:12:44 am
content: Quote from: OwO on April 06, 2019, 01:42:24 pmThis is the worst advise i have read in a long time. Yes its not simple but its not rocket science, and bringing pnp in house transformed our business.

author: kayvee
author_rank: Regular Contributor
timestamp: April 11, 2019, 11:22:28 am
content: Quote from: mrpackethead on April 11, 2019, 11:12:44 amAbsolutely agree with mrpackethead on this one.We are a small company and it absolutely can be done with little fuss and a little bit of knowledge.One of the better decisions I have taken.

author: kylehunter
author_rank: Regular Contributor
timestamp: April 11, 2019, 11:47:09 am
content: Quote from: Reckless on April 11, 2019, 05:48:23 amI believe it to be lead-free capable, but I will double check for sure.Quote from: Styno on April 11, 2019, 11:11:33 amYeah, those two reasons (along with Juki feeders being more reliable) that I have for "upgrading" to the Juki. While I was at the shop, a Juki 2070 did a test board with like 50 01005's without any trouble whatsoever. The 2060 is rated to 0201's, which for the time being is smaller that we will need (we use 0603's and occasional 0402's).EDIT:It is an assembleon Opal Xii, not a Topaz, so the assembleon is 0201 capable as wellQuote from: kayvee on April 11, 2019, 11:22:28 amYeah, I highly doubted you need that much infrastructure in place. Of course, it is a massive undertaking, and I wouldn't ever downplay that fact. But on the thread of the P&P lifestyle, it seems like most of the people with the horror stories either bought cheap machines, used machines that had to be repaired, or didn't have a service/support center nearby.

author: jmelson
author_rank: Super Contributor
timestamp: April 11, 2019, 07:19:43 pm
content: Quote from: mrpackethead on April 11, 2019, 11:12:44 amRight! We make small runs of PC boards, selling a few hundred per year, with about 15 different models. We got a Philips CSM84. a 3-nozzle machine that is kind of an earlier version of the Opal. The 6.5 mm component height limit is a bit of a limitation, but not really serious. Otherwise, the machine is VERY flexible, so we use it for parts ranging from 0603 up to 20 mm square FPGAs.Our machine doesn't have vision, so alignment is fine down to SOIC, but is a bit iffy on .65mm lead pitch and finer.Anyway, it is certainly one of the best investments I made, and beats hand assembly by a factor of 100 X or so. Over the last 12 years, we have had just a few breakdowns with the machine, and I was able to fix them all, although some of them took a while to diagnose.As for setup, I'm still learning, but I was in full production with it within one week of the machine's arrival. And, I'd never even seen a P&P in real life before getting this one. (I did do a lot of research before committing to this one.)Note that all the Gem series of machines require 3-phase power, which I don't have here.Jon

author: coppercone2
author_rank: Super Contributor
timestamp: April 12, 2019, 12:28:29 am
content: dave jones has some videos on making the PCB testable.The best method is to get more layers and route test traces to a test header (optimal) or some kind of test side-card thing (worse but still good). Dave jones actually makes it so the master PCB panel has traces going to it, so the entire panel is tested at once, then the boards are broken out.The next option is to put extra pads on your PCB so that a 'bed of nails' tester can be used and hooked up to either a home-made test box that a technician cycles through, or a DAQ system... I.e. something like a Fluke Hydra, or NI stuff if you have money and time to set it up. Keep in mind current measurement is a problem unless you put the shunts on the PCB and absorb the cost, if you need to measure current in circuit subsections.If you make a bed of nails the thing you need to worry about is stiffness. Make it out of really thick plastic and make a good base for the PCB (like with holes under the components so as much of the PCB as possible is being supported by heavy plastic), because when you compress it with all the pogo pins it will tend to bend. Like make a seperate base for every PCB with holes drilled under all the components so that as much of the PCB as possible sits flat in the tester. It should also be static dissipative.The next option is obviously just paying a tech to sit with bench equipment and manually probe it. This will usually be slower and more error prone and prone to blowing up the circuit if probes slip on high density stuff. And people can rip parts off the board sometimes. A more advanced tech will probobly make their own adapters and simple jigs etc to speed it up, but it won't be as fast as a engineered tester or a multilayer board with a seperate test plane that connects to a DAQ through a single cable. On the other hand so long he shows up to work you can get the tests done, a test box fucking up = problem.However, even if you decide to hire people, it is merfitful to make the supported base that holds the PCB absolutely stable and prevents flexing during probing. Less chance of slipping etc and probobly faster and more reliable then a panavice.You can literarly take the gerbers, put em in MS word and draw colored circles over all the raised parts, print it out, spray-glue it to your substrate and drill holes.Would be best if you leave a few spare holes on the PCB so that pins can be used to fix the board into place. Like use your feducials for it. Also would help in bed of nails tester (you can even screw it down with larger thumbscrews if space is available).https://www.mouser.com/ProductDetail/Smiths-Interconnect-IDI/S-3-H-4-G-S-C-SS-SPGS?qs=1%2FkFHMS5B%2Fj7cxIPv8BgqQ%3D%3D&gclid=CjwKCAjwy7vlBRACEiwAZvdx9iIu9I1YRoETSwKLwz64TvqVB5Ii8r4nRfLKgqKpb8ZRfNztWJy9WRoCZiUQAvD_BwEMain skills required would be precision layout of drill holes to build the tester. With some kind of jig borer, mill, or cnc if you are good with that it would be easier.The problem with using the PCB with spring contacts as you have in mind is flexing and solder cracking from stress. For mass production you want something really beefy IMO. PCB is not meant to be used as a panini press.

author: kylehunter
author_rank: Regular Contributor
timestamp: April 13, 2019, 12:41:29 am
content: Quote from: coppercone2 on April 12, 2019, 12:28:29 amWow thank you so much, that is really useful information! I guess it really just depends a lot on the specific boards also, and what data is needed from the testing.One question I've had on bringing the traces out on the panel for testing. Don't you worry about when you break the boards out, that the traces could short out on something since they are exposed on the edge of the board?

author: mrpackethead
author_rank: Super Contributor
timestamp: April 13, 2019, 05:08:46 am
content: I've looked at this test method, of bringing the tracks out.. I'm not convinced its a great idea, but i can understand why Dave things its got merit. Like many things there are often differnet ways of doing thigns and often you can acheive an outcome in multiple differnet ways..