hybridfree/eevblog-posts huggingface dataset:
Component supply crunch? - Page 1
Forum section: electronics / general

author: JohnG
author_rank: Frequent Contributor
timestamp: April 17, 2018, 08:18:07 pm
content: My company has seen some common items (certain resistor values, etc.) go out of stock with long lead times. Anyone else seeing this? Just curious.John

author: CJay
author_rank: Super Contributor
timestamp: April 17, 2018, 08:26:11 pm
content: People panic buying ahead of tariff impact?

author: darrellg
author_rank: Unknown
timestamp: April 17, 2018, 08:42:12 pm
content: https://epsnews.com/2017/10/19/component-shortages-to-last-longer-than-expected/

author: ataradov
author_rank: Super Contributor
timestamp: April 17, 2018, 09:11:58 pm
content: Yeah, buying generic ceramic capacitors is a pain at the movement. Some of that is probably due to Yageo pullout and others failing to adjust to increased demand.It started way before the tariffs stuff, so it is something else.

author: bd139
author_rank: Super Contributor
timestamp: April 17, 2018, 09:40:30 pm
content: Probably fallout from the cartels that got owned recently.I have noticed the same trouble. Fairly common parts are drying up.

author: Dr. Frank
author_rank: Super Contributor
timestamp: April 17, 2018, 09:51:56 pm
content: There's allocation on chicken food, like certain resistors (1206), MLCCs, coils, then on FETs, and even on special ICs and µPs.That's daily business, which is sinking a lot of R&D effort, just to circumvent the faults of sales and purchasing.

author: JohnG
author_rank: Frequent Contributor
timestamp: April 19, 2018, 12:35:15 pm
content: Ok, so I am not imagining it.
Manual solder paste printer. - Page 1
Forum section: electronics / general

author: hugeone
author_rank: Contributor
timestamp: April 17, 2018, 11:56:15 pm
content: Hi.I want to buy solder paste printer from China (probably via aliexpress) . Which one would you recommend?Thank you

author: l0wside
author_rank: Regular Contributor
timestamp: April 18, 2018, 07:36:35 am
content: You have two options:* Buy a printer for framed stencils. Pro: printer is cheaper. Con: stencils are effectively only available from China, framed stencils are more expensive than unframed, shipping cost might be higher than for unframed due to size and weight.* Buy a printer for unframed stencils. Pro: stencils available from virtually any supplier in the world (including China). Con: printer is typically more expensive.You might want to look for a used printer, they typically do not wear off.

author: hugeone
author_rank: Contributor
timestamp: April 18, 2018, 09:36:52 am
content: I personally prefer the framed ones. Less work and you do not purchase then to oftenas they last for a while.Actually I asked if someone has something to recommend as the quality of the Chinese products is a bit random

author: girts
author_rank: Contributor
timestamp: April 18, 2018, 09:15:51 pm
content: Quote from: l0wside on April 18, 2018, 07:36:35 am+ a lot of storage space necessary.Why not to prefer unframed stencils if you are looking for manual printer anyway? Like these -http://www.spide-smt.nl/products.html
Coil Winding Machine Recommendations - Page 1
Forum section: electronics / general

author: magicsmoke
author_rank: Regular Contributor
timestamp: April 17, 2018, 07:54:59 am
content: Does anyone have any recommendations for manual or low cost motorized (CNC preferred) coil winding machines? The targeted applications are bobbin winding and three phase armature stators. Ideally I would like to be able to control the lay of the coil in bobbin wound applications. Currently don't have time to build one myself.A couple of manual machines:http://www.whitelegg.com/products/electric-motor/electric-motor-rewind-and-repair/sub/coil-winding-equipment/hand-operated-coil-winding-machineshttp://www.armaturecoil.com/bench-type-hand-coil-winder/Or cheap CNC machines (Many similar to it):https://www.ebay.com/itm/Computer-CNC-Automatic-Coil-Winder-Winding-Machine-for-0-03-1-2mm-wire-110v-220v/371889517483?epid=2159870132&hash=item569657b3ab:g:ia8AAOSwAC1Z5rsSAny place else I should look for reviews or recommendations?
assembly od sma stainless steel connector - Page 1
Forum section: electronics / general

author: sdouble
author_rank: Frequent Contributor
timestamp: April 24, 2018, 06:07:32 am
content: Hi all,I intend to develop a board which will include a bunch of SMA connectors.My plan is to go for stainless steel connectors instead of standard brass ones.Would you know if that choice could lead to any problem in the assembly phase ?the connectors will be rather similar to that one :https://www.ebay.com/itm/20x-SMA-RA-thru-hole-female-jack-bulkhead-O-ring-right-angle-PCB-Mount-Connector/273166220321?hash=item3f99f9bc21:g:8SsAAOSw4GVYPU0Rbut SS made and unplated.thanks for your feedback
PCB cross-section is included with the order... That's a first! - Page 1
Forum section: electronics / general

author: ar__systems
author_rank: Frequent Contributor
timestamp: April 03, 2018, 02:45:14 pm
content: Tried a new PCB house. The order came with a small piece of PCB cut and encapsulated in plastic for inspection. Wow, I've never seen anything like that in 17 years!

author: PTR_1275
author_rank: Frequent Contributor
timestamp: April 03, 2018, 03:03:16 pm
content: Every production pcb batch we order gets one. Has the report for copper thicknesses and via thicknesses etc... they grind one side so it goes through a via for confirmation they are not lying to us.A friend of mine recently ordered some pcbs from a cheap online service and got one of the plugs as well.If you have a good enough microscope / macro lens on a camera and a reference slide, you can do measurements of the copper yourself.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: April 03, 2018, 03:19:46 pm
content: Oooh, nice!Who does that? And when -- is there a flag on the order form to receive a test coupon, or do they do it for orders of more than X pieces/area, or?I've also not seen anyone that does that, but I'm aware of the method, as I've seen (and done!) metallurgical sectioning before.Tim

author: asmi
author_rank: Super Contributor
timestamp: April 03, 2018, 04:02:35 pm
content: OurPCB always includes PCB cross-section sample.

author: Alex Eisenhut
author_rank: Super Contributor
timestamp: April 05, 2018, 12:35:53 am
content: We always get a cross-section for blind and buried mixed material boards. Makes me look important when I'm at the microscope...There's never anything wrong I can see.

author: ovnr
author_rank: Frequent Contributor
timestamp: April 05, 2018, 12:43:32 am
content: Huh, neat. Looks like it's cast in the plastic first, then ground and polished. Didn't think that was common for test coupons like this.

author: KE5FX
author_rank: Super Contributor
timestamp: April 05, 2018, 12:52:33 am
content: Looks like that section came from WellPCB.

author: RobK_NL
author_rank: Frequent Contributor
timestamp: April 05, 2018, 11:41:40 am
content: 5pcb do this as well. Also a piece (usually a quarter or so) that they used for solderability testing and a five page test report.

author: ar__systems
author_rank: Frequent Contributor
timestamp: April 05, 2018, 12:29:02 pm
content: Quote from: Alex Eisenhut on April 05, 2018, 12:35:53 amMakes sense for multilayers with custom stacks... These are simple 2 layers

author: Alex Eisenhut
author_rank: Super Contributor
timestamp: April 05, 2018, 10:34:24 pm
content: Quote from: ar__systems on April 05, 2018, 12:29:02 pmI'm doing some spring cleaning, I can mail you one!
The perfect POGO pin I have been looking for. - Page 1
Forum section: electronics / general

author: GreggD
author_rank: Regular Contributor
timestamp: April 03, 2018, 02:56:14 pm
content: Normal pogo pins that are ~31mm long are hard to use.Short pins from Milmax are $2 each.I have been searching for years for the perfect, easy to use, and cheap pin.I'm not a shill but,Here it is PGTH600 found on Aliexpress. Search for PGTH-xxxx on Google.The 600 is 6mm tall, 1.85mm compression. The solder tail is 1.85mm long and 0.85mm diameter so it fits in the same hole as a standard 2.54mm header.These work great in place of standard 2.54mm headers so when you make a pcb with bottom test points, make a 2nd one for pogos and testing.Available 10, 50 & 100. I got 100 with shipping for $17I am a happy camper.

author: ataradov
author_rank: Super Contributor
timestamp: April 03, 2018, 04:55:08 pm
content: Can you give a link to one of the listings? I'm not finding anything.

author: GreggD
author_rank: Regular Contributor
timestamp: April 03, 2018, 05:15:59 pm
content: Qu:10https://www.aliexpress.com/item/10pcs-Spring-Loaded-Pogo-Pin-Connector-2-mm-2-5-3-3-5-4-4-5/32829246846.htmlQu:100https://www.aliexpress.com/item/100pcs-Spring-Loaded-Pogo-Pin-Connector-2-2-5-3-3-5-4-4-5-5/32828716758.html

author: ataradov
author_rank: Super Contributor
timestamp: April 03, 2018, 05:28:10 pm
content: Cool thanks. It looks like the actual manufactures is called TangDa, and searching for "tangda pogo pin" gives a lot of results in other places, including eBay.
SMD Bus Bars  - Page 1
Forum section: electronics / general

author: Marchello
author_rank: Contributor
timestamp: March 14, 2018, 08:53:57 am
content: Hello!Does anyone know where to find similar SMD BusBars for PCB power lines? (preferably several different sizes)BRMark

author: ar__systems
author_rank: Frequent Contributor
timestamp: March 14, 2018, 03:32:02 pm
content: I doubt these huge chunks of metal will be able to get hot enough in the time normal reflow process takes.

author: Marchello
author_rank: Contributor
timestamp: March 14, 2018, 04:41:58 pm
content: I made several custom copper buses with dimensions of 20x4x1mm. and soldered them with our standard thermoprofiles absolutely without any problems.It remains to find something similar from component manufacturers.

author: Marchello
author_rank: Contributor
timestamp: April 02, 2018, 08:41:54 am
content: Someone, please!

author: max_torque
author_rank: Super Contributor
timestamp: April 03, 2018, 06:36:13 pm
content: I just get Laser or waterjet cut "profiles" taken out of copper sheets of the correct thickness. Watch out for the differing thermal expansion on long lengths, you might want to include some basic forming (bent sections) to absorb that expansion without resulting in the soldering failing or the pcb cracking eventually

author: Marchello
author_rank: Contributor
timestamp: April 04, 2018, 10:47:41 am
content: Quote from: max_torque on April 03, 2018, 06:36:13 pmThanks for answer!I thinking about waterjet cut, but also about one problem - finish soldering coating.BRMark

author: langwadt
author_rank: Super Contributor
timestamp: April 04, 2018, 11:13:58 am
content: Quote from: Marchello on April 04, 2018, 10:47:41 amcustom rf shielding cans and such are usually make with photo etch

author: thm_w
author_rank: Super Contributor
timestamp: April 04, 2018, 07:40:41 pm
content: There are a few varieties here, but its not cheap:http://uk.farnell.com/c/connectors/connector-tools-accessories/jumpers-shuntsIf you also google "tin plated copper bar" you will find some bus bar or metal suppliers, then you will need to have it cut to length (could be done with a bandsaw or similar).These are just a bit too big:http://www.elektronordic.eu/copper-busbars.html12 x 5 mm, but smaller ones should exist.

author: daqq
author_rank: Super Contributor
timestamp: April 05, 2018, 04:57:15 pm
content: QuoteCould you have it cut out of a tin plated sheet? The sides might be a bit of a problem, but with proper flux they should solder quite nicely, even if they are raw copper.

author: tszaboo
author_rank: Super Contributor
timestamp: April 05, 2018, 05:09:26 pm
content: The last time I had to use busbars, they were custom designed, and manufactured to our spec.If you want just a little more current in your PCB, Harwin has these, but these are small.https://www.harwin.com/filter/?level=3&code=HLF&tlcode=H
Looking For EURO-Circuits Smd Reflow Equipment Reviews - Page 1
Forum section: electronics / general

author: johnny
author_rank: Newbie
timestamp: March 21, 2018, 09:53:26 am
content: Hi,I am looking for reviews of EURO Circuit's SMD Reflow Equipment. I have not found any first-hand user experience for their machines. I would be grateful if someone provides it.Thanks.https://www.eurocircuits.com/new-smd-reflow-equipment/

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: March 21, 2018, 10:03:18 am
content: The stencil printer is good but very overengineered, and so quite expensive. Their pin locating system works very well with stainless stencils. Less useful for plastic ones.

author: jc101
author_rank: Frequent Contributor
timestamp: March 21, 2018, 06:02:42 pm
content: For prototypes they do a thing called eC-stencil-fix with is 20 Euro - if you order PCBs with their eC-registration option and a stencil you can easily use it. No good for quantities for but for a few of something it's cheap and easy to use. I have one and it works fine.I also have one of the reflow ovens, the previous generation to the one currently available, works quite well with reasonable software to create profiles etc. I only use it for prototypes and when I need only a few of anything. I also have the hood for it, when hooked up to a pretty beefy fan it does a reasonable job, although you need a well ventilated space really.Last time I also has a additional thermocouple in there the whole oven managed to be within +/- 10 degrees of the set temperature - which is fine for what I need.Quite like the stuff, seems to do exactly what it says it should, although you do pay for that.

author: johnny
author_rank: Newbie
timestamp: March 22, 2018, 10:42:29 am
content: Thanks for your reply guys. appreciate it.

author: girts
author_rank: Contributor
timestamp: March 26, 2018, 03:02:57 am
content: Quote from: jc101 on March 21, 2018, 06:02:42 pmOnly one thing to say in addition - if thermocouple is not properly attached to PCB (inserted into hole etc.), process never ends. Result - burned board. Software tries to stabilize temperature, but it can't.Otherwise excellent oven.
P.C.B. foam etching machine without nozzles or air stones - Page 1
Forum section: electronics / general

author: micha1102b
author_rank: Contributor
timestamp: March 22, 2017, 03:26:34 pm
content: Hi there,interested in a new generation of p.c.b. foam etching machines (D.I.Y.)?No more need of compressors attached to batteries of air stones or ever corroding liquid pumps with always blocking nozzles.Watch this short clip on YouTube.https://youtu.be/OmKdW3QI5esThanks and best regardsMike

author: free_electron
author_rank: Super Contributor
timestamp: March 22, 2017, 03:46:28 pm
content: venturi pump ?this years awards for most creative etcher design goes to you.

author: micha1102b
author_rank: Contributor
timestamp: July 24, 2017, 06:29:52 am
content: Hi there,the second edition of my PCB etching machine is now working.If interested, contact me for the full construction guide (pdf).And please go on with sending in your suggestions and ideas for further improvement.Best regardsMicha

author: RoGeorge
author_rank: Super Contributor
timestamp: July 24, 2017, 06:41:07 am
content: Nice machine in the video!When I read 'foam etching' in the title, I thought it is about the 'dish sponge + FeCl3 + PCB inside a zip-lock bag' method.The sponge etching is very clean, simple, fast and economic. Just squeeze the sponge bag for a while, and that's it. It's a very clean method (simply dispose the whole zip-bag after etching), much faster then bubble etching or hot&agitated bath, and you don't need so much FeCl3 as in a bath etching.

author: micha1102b
author_rank: Contributor
timestamp: July 28, 2017, 02:05:22 pm
content: Hi there,the second edition got an update.Now PCB with sizes up to 43x20 cm can be etched. That's more than enough....Best regardsMicha

author: albert22
author_rank: Regular Contributor
timestamp: July 29, 2017, 05:15:05 pm
content: Quote from: free_electron on March 22, 2017, 03:46:28 pmIt looks like an air lift pumphttps://en.wikipedia.org/wiki/Airlift_pump

author: micha1102b
author_rank: Contributor
timestamp: March 25, 2018, 02:59:14 pm
content: Hi,still lots of requests for the PDF construction guide are coming in.Some interested guys later email me asking whether the machine could be made less high.Unfortunately I didn't mention this in the document: Since the machine is based on the "air lift pump"-system,every cm less in height than described would reduce the etchant pump efficiency (i.e. output) exponentially.So the answer is NO if you wish to use it without airstones and with such a tiny 5 watt air pump.Of course, applying a high power air compressor and the use of airstoneswould make an overall height reduction possible, as many other examples described in various websites clearly prove.Best regards

author: rx8pilot
author_rank: Super Contributor
timestamp: March 25, 2018, 04:38:29 pm
content: That is actually pretty cool.I am still scared of the chemicals and still waiting for a clever way to make multilayer PCB's reasonably easy.
Getting small quantities into tape (cut or reel) - Page 1
Forum section: electronics / general

author: JohnG
author_rank: Frequent Contributor
timestamp: March 23, 2018, 01:06:50 pm
content: I have a situation where I would like to mount some 0402 resistors upside down, i.e. the resistive element is adjacent to the PCB surface. I do not need large quantities, maybe 1000-2500 pieces of 3 or 4 different values, and this is uninteresting to the manufacturer.Does anyone know of a service that could take a reel or some cut tape and retape the parts upside down?Thanks,John

author: ar__systems
author_rank: Frequent Contributor
timestamp: March 23, 2018, 02:42:23 pm
content: I don't have an answer to your question, but I'm curious what is the reason for that?

author: JohnG
author_rank: Frequent Contributor
timestamp: March 23, 2018, 05:06:04 pm
content: I am using multiple parallel resistors as high speed current shunts in a high speed current pulse generator. I have found that mounting them upside down can reduce the total shunt inductance by about 100-150 pH. This lets me get both about 3x the bandwidth from the shunt and lowers the inductance in the circuit enough to make a difference.John

author: rx8pilot
author_rank: Super Contributor
timestamp: March 23, 2018, 05:13:19 pm
content: How much money is a solution worth to you? Your options are directly proportional to your budget.Short and misplld from my mobile......

author: Gribo
author_rank: Frequent Contributor
timestamp: March 23, 2018, 06:15:59 pm
content: Certain manufacturers offer face down packing option.https://ims-resistors.com/passive-smt-mounting-techniques-face-vs-facedown-performance-trade-offs/

author: JohnG
author_rank: Frequent Contributor
timestamp: March 23, 2018, 09:09:47 pm
content: Quote from: rx8pilot on March 23, 2018, 05:13:19 pmGood question...I don't have a solid answer, and it would involve some discussion. That discussion would go a lot easier if I have some idea what those options are and some ballpark pricing.I do know that our assembly house will not do it at all unless it comes in the tape with the desired orientation. Also, I know it is too expensive for me to do it by hand.John

author: hcglitte
author_rank: Regular Contributor
timestamp: March 24, 2018, 09:40:23 am
content: This may not be applicable for you. However, if you have your own p&p you could make a flipping station ().Make the p&p place the part into the station, then let it pick it up with top visual recognition.
pcb manufacturing process - Page 1
Forum section: electronics / general

author: ansonbao
author_rank: Regular Contributor
timestamp: March 22, 2018, 07:43:35 am
content: I explain the pcb technology here sometimes,but I know so many people still confused about how pcb are manufactured in a factory.To be honest,it is really a complex process.So I made a flow chart to show the process step by step and pcb classification, please check the attachment. you can share this anywhere and any questions please tell to me.
this PLA material will be easily broken ? (3D Printer) - Page 1
Forum section: electronics / general

author: ammjy
author_rank: Regular Contributor
timestamp: March 12, 2018, 07:01:07 pm
content: Hello ! i have a question..i should print this..this size PLA will broken easily ?this little part recive power from micro RC Servo.i already checked 2mm ABS is fine. (why not ABS. ABS have strain after print)i need your experience.Please, let me know !

author: Rerouter
author_rank: Super Contributor
timestamp: March 12, 2018, 07:17:34 pm
content: on a normal hot extruder printer, yes I would say that is pushing too thin, in part because it will also be likely to warp when being printed due to its tiny size,If you babied it while printing just that part and ramped back the speed and heat you could print it, however its stenth would not be amazing,Could you instead use an "eyelet screw" screwed in to the main material?

author: ammjy
author_rank: Regular Contributor
timestamp: March 12, 2018, 07:45:14 pm
content: aa Thanks you for reply, Rerouter !!hmm... cuase of Aileron axis... i can't use some screws...

author: benst
author_rank: Regular Contributor
timestamp: March 12, 2018, 09:52:57 pm
content: Perhaps print it in PETG material?Also, make it longer at the back. Now it goes straight down. Why not angle it at 45 degrees? That might give it more material and strength.Ben

author: Kean
author_rank: Unknown
timestamp: March 15, 2018, 02:05:36 am
content: Even if you could print it, it would break very easily.Can you print the pyramid shape with a centre slot, and glue in some stronger sheet material cut to shape? (e.g. carbon fibre, FR4, etc)

author: hendorog
author_rank: Super Contributor
timestamp: March 15, 2018, 03:24:30 am
content: If you don't use a yoke to connect to it then it will not need to be as thin.You could make it much thicker and use a long bolt and an eyelet instead.

author: asmi
author_rank: Super Contributor
timestamp: March 17, 2018, 06:40:14 am
content: Using PLA for any functional parts that are going to be subjected to any sort of mechanical stress is a terrible idea, as it often breaks "with a bang", meaning many small pieces tend to fly away in all directions (kinda like a glass).I always use PETG for such parts because it's much stronger while still being somewhat elastic - so it fails more gradually. Also it can be easily "post-processed" mechanically after printing to aid fitting. For example, I often print cases for my boards out of PETG, and then make a thread M3 using regular metal-work tools. This thread is strong enough to hold a screw, and withstands seemingly any number of installation-removal cycles. And the filament I use is produced locally, so I support a local business!

author: hagster
author_rank: Frequent Contributor
timestamp: March 17, 2018, 07:40:46 am
content: I would redesign it so it can be rotated 90 degrees and lay flat on the bed. That will give you most strength in what looks like the axis required.
Part Placement accuracy - Page 1
Forum section: electronics / general

author: gogoman
author_rank: Regular Contributor
timestamp: March 14, 2018, 01:25:16 pm
content: How accuracy can a part be place on a PCB.the part in question is in a tight location and needs to be place within 3mils of it center.is this possible?thank

author: ar__systems
author_rank: Frequent Contributor
timestamp: March 14, 2018, 03:29:00 pm
content: Everything is possible. But might get expensive

author: DerekG
author_rank: Frequent Contributor
timestamp: March 15, 2018, 12:28:40 am
content: Quote from: gogoman on March 14, 2018, 01:25:16 pmThat was not good board design from the start. If you can't manage to get the assembly reliably done, you might well have to redesign the board.Perhaps have this part placed on the board first using optical placement & hope it does not move while the other components are being placed. Often components can move by "several mils" in the infrared/vapour phase oven. To minimise this movement you might have to use a very thin solder paste stencil - which might cause other problems around the board.

author: katy201607
author_rank: Contributor
timestamp: March 15, 2018, 10:23:41 am
content: You are correct. if the package is too small, and pads, holes will be smaller in PCBs, it will cost much!
Advanced PCB fab, is this price fair? (probably is :) - Page 1
Forum section: electronics / general

author: Psi
author_rank: Super Contributor
timestamp: March 07, 2018, 08:34:48 pm
content: So i'm getting a PCB made that uses some more advanced processes (filled & plated 0.1mm microvia's)and I just want to run the quoted cost past people on here for confirmation that it's reasonable.* qty of 5 boards (each has a few subboards)* Total Board size = 144mm x 74mm* 4 layer* ENIG* 1mm thick* Quantity - Drill size27x 0.1mm laser drill micro via - plugged and then plated on top360x 0.15mm laser drill micro via - plugged and then plated on top202x 0.2mm51x 0.4mm178x 0.5mm89x 0.7mm108x 0.9mmtotal holes = 1015* 1.5 mm route path (design includes 4 sub-modules on break-out tabs)* 4/4mil track/gapQuoted cost at PCBway is US$524 + 35 shippingDoes that sound like a fair price?Unfortunately i can't post a pic of the PCB as it's for work.But all the holes are for an array of very tightly packed 0402 components as well as a 0.4mm pitch BGA and misc other stuff.

author: rea5245
author_rank: Frequent Contributor
timestamp: March 07, 2018, 08:50:32 pm
content: Have you tried entering your board's specs atPCBShopper.com? It's a price comparison site for PCBs, and you'll be able to quickly see what two dozen different manufacturers (including PCBWay) would charge.Disclosure: I run PCBShopper.- Bob AlexanderPCBShopper.com

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: March 08, 2018, 10:33:46 am
content: As soon as you move away from pooled service specs, low volume orders are mostly tooling cost, which will vary a lot between suppliers.Tryhttp://www.safe-pcb.comas they offer lots of options on their online quote page

author: katy201607
author_rank: Contributor
timestamp: March 17, 2018, 04:48:03 am
content: 0.1 mm lazer drill cost really much. if you have gerber file, may i can help to get some quote.
tinned wire - Page 1
Forum section: electronics / general

author: stern0m1
author_rank: Contributor
timestamp: March 13, 2018, 10:08:51 pm
content: I got a few quotes for companies in china for wire harnesses. They are all offering tinned copper wire. When I asked for bare copper wire basically they want more money. They all tell me the standard is tinned. Additionally looking around just for plain wire from china it looks like they all advertise as tinned.I'm just wondering if i'm missing something. Tinned wire should be more expensive than not tinned. Is there some catch? Is there some characteristic of copper wire that can be made cheaper if the wire is tinned?Thanks

author: sleemanj
author_rank: Super Contributor
timestamp: March 13, 2018, 10:17:50 pm
content: Demand leads supply. Less demand for untinned copper wire than there is for tinned copper wire.

author: frozenfrogz
author_rank: Frequent Contributor
timestamp: March 13, 2018, 10:28:14 pm
content: At least here in Germany, tinned copper wire is more expensive then pure copper wire - up to 30% more or so, because of the extra step involved.Don’t want to offend anyone here, but with Chinese manufacturers you need to be very picky. If "tinned copper wire" is so much cheaper it may very well be that the supplied wire is actually just any ChinesiumTMalloy including some percent of copper. After tinning, you would not be able to tell a difference in visual appearance from tinned pure copper wire.From what I have encountered in various cheap PRC built machines, you will even find tinned iron wire or aluminium alloys.To be on the safe side, request real production samples for thorough inspection and dearly specify the materials prior to ordering.

author: sleemanj
author_rank: Super Contributor
timestamp: March 13, 2018, 10:59:05 pm
content: Tinning is easy to scrape away to confirm that the underlying material at least "looks like copper".I buy silicone wire from China in small lots (20M or less at a time), the main supplier I use sells both and tinned is cheaper than untinned, the thicker gauge the bigger the difference. 20AWG is only 0.1CNY difference (less than 5c/meter) but specs are the same, the sales numbers do seem to favour tinned.

author: ar__systems
author_rank: Frequent Contributor
timestamp: March 13, 2018, 11:21:41 pm
content: It might be tinned somethingI once bought some Chinese F-F jumpers that had weird wires. They could only be soldered if you manage to do that in under 1 secondafter that they just would not wet with solder no matter the amount or type of flux I tried. I tried to scrape them with a knife and it was not a copper
Countersunk holes on PCB  - Page 1
Forum section: electronics / general

author: dino
author_rank: Contributor
timestamp: March 03, 2018, 08:06:22 pm
content: Hi all,I'm making an enclosure cover from FR4 with black soldermask, and it would be great if I could mount it using countersunk screws.Does anybody know a PCB manufacturer that can make a PCB with ~2.6mm countersunk holes? (for M2.3 screws)Preferably in Shenzhen.

author: IconicPCB
author_rank: Super Contributor
timestamp: March 05, 2018, 06:37:58 am
content: Dino.Poshalji mi gerber/dxf.Ja proizvodim shtampu u prototipnoj izradnji.Proces proizvodnje se zasniva na mehanichkoj obradi bakra.Zenkvane rupe nisu problem.

author: Jeroen3
author_rank: Super Contributor
timestamp: March 05, 2018, 07:34:00 am
content: Eurocircuits can do this.

author: noras
author_rank: Contributor
timestamp: March 05, 2018, 07:48:24 am
content: Some manufacturers can do in Shenzhen!

author: dino
author_rank: Contributor
timestamp: March 08, 2018, 09:05:38 pm
content: Quote from: IconicPCB on March 05, 2018, 06:37:58 amHvala na ponudi, treba mi veca kolicina, ENIG + mat crn soldermask, i osetljiv sam na cenu, pretpostavljam da ti to nije interesantno.Quote from: Jeroen3 on March 05, 2018, 07:34:00 amQuote from: noras on March 05, 2018, 07:48:24 amSo far I found PCBWay in Shenzhen, if you insert countersunk holes, price is raised by more than two times at >100pcs.My guess is that Eurocircuits is similar.

author: IconicPCB
author_rank: Super Contributor
timestamp: March 08, 2018, 09:25:52 pm
content: Pozlatu ne radimo.Nudimo samo srebro.Razlog je kojekakva opasna i zakonom regulisana hemija koja se koristi u prpizvodnji pozlate.Svi smo osetljivi na cenu i mi koji pokushavamo da se hvatamo u koshtac sa kineskim cenama znamo koliko shta koshta.A ti ako hocesh poshalji informaciju i mi cemo ti odgovoriti sa ponudom.Mogu da t ikazhem da imash relativno dobrog proizvodjacha EIPCB u Nishu a isto tako i jednu manju radionicu to negde u Novom Sadu cini mi se.Ako je tvoj zahtev relativno jednostavan i u pitanju je samo oblik i vrsta rupe to nebi trebalo da predstavlja neki narochit problem u proizvodnji,Manufacturing seeks places with cheap labor cost and weak currency.Soon enough China will price itself out of the game and some other country ( Vietnam for example ) will be the new what ever.

author: DerekG
author_rank: Frequent Contributor
timestamp: March 09, 2018, 01:19:28 am
content: Quote from: dino on March 03, 2018, 08:06:22 pmIf the cost increase is too great from the board shop, you could extend out the solder mask a little more & countersink the 2 holes yourself on the drill press. Once you set the drill press stop, it would take you less than 20 seconds tops. A black screw head would be nice

author: wraper
author_rank: Unknown
timestamp: March 09, 2018, 01:50:58 am
content: Quote from: dino on March 08, 2018, 09:05:38 pmI don't think that price increase would scale as much, however Eurocircuits is many times more expensive to begin with.
Experience with WLCSP and MAPBGA packages - Page 1
Forum section: electronics / general

author: jbrookley
author_rank: Newbie
timestamp: March 19, 2018, 11:23:15 pm
content: Hello everyone!I'm designing a board with NXP's K26 microcontrollers and debating between WLCSP and MAPBGA packages. The WLCSP package is obviously preferred because of the smaller footprint but I was wondering if anyone here has had any experience with either of those packages, either from a manufacturing or general use experience (issues with circuit board flexing causing loss of connection, shorts, etc). Not entirely sure where the best place to put this would be so this seems as good a place as any other!Here are some links for the two packages (for reference):169 pin WLCSP package:https://www.nxp.com/docs/en/package-information/98ASA00640D.pdf169 pin MAPBGA package:https://www.nxp.com/docs/en/package-information/98ASA00628D.pdfThanks!
Just another flux topic  - Page 1
Forum section: electronics / general

author: josip
author_rank: Regular Contributor
timestamp: February 25, 2018, 11:04:47 am
content: I am buying parts at Mouser (free shipping), and I want to add some flux (for SMD hand soldering) in my next order. I read good things about MG Chemicals 835, but unfortunately this one can't be shipped by air, and like most other fluxes on Mouser, there isShipping Restrictednote.Available MG Chemical products (withoutShipping Restrictednote) are: 836-P, 8342-50G, 837-P, 8341-10ML, 8351-1L. If somebody have any experience whit some of this, let me know. It is also available NF372-TB from Kester.There are good reviews for Edsyn FL 22, so I sent e-mail to local Farnell about prices for 2530038 FL 22 YFL, 1863327 FL 22 R and 2467647 FL 22 CL. Didn't receive answer, yet.

author: NorthGuy
author_rank: Super Contributor
timestamp: February 25, 2018, 01:51:22 pm
content: Quote from: josip on February 25, 2018, 11:04:47 amI use 8341. Works fine.

author: josip
author_rank: Regular Contributor
timestamp: February 25, 2018, 03:05:26 pm
content: Quote from: NorthGuy on February 25, 2018, 01:51:22 pmAnd what about cleaning PCB, after using of 8341? Can I leave it without cleaning?

author: NorthGuy
author_rank: Super Contributor
timestamp: February 25, 2018, 05:38:34 pm
content: Quote from: josip on February 25, 2018, 03:05:26 pmYou don't have to clean it. I usually clean after first soldering, but when I change something afterwards I don't, so it just stays there. Everything works fine.
Sn64Bi35Ag1 Solder Paste - Page 1
Forum section: electronics / general

author: mgbolts
author_rank: Contributor
timestamp: February 17, 2018, 02:24:09 pm
content: Tested new solder paste today. I did did a VERY poor job smearing the paste roughly across the pads on a proto board with more on the board than the pads.Was using leaded chemtools before but WAS VERY unhappy with the amount of flux residue....Tested a new paste today, Yoshida Med temp Sn64Bi35Ag1. Have to say that I am very happy, behaves just like leaded using same reflow profile. My new go to!Supposed to be No Clean but given my poor application it was not perfect but still pretty good and way better than before. I think it should 'clean up' very nicely when applied with a stencil.Cost was around US$7.50 for 100gm tube on TBCheers
Need SMD connector for through PCB connection - suggestions? - Page 1
Forum section: electronics / general

author: Yellofriend
author_rank: Regular Contributor
timestamp: February 20, 2018, 06:57:37 am
content: I am looking for some suggestion how to connect something on the other side of a SMD PCB. Right now I use normal through hole connectors, but that requires handsoldering. Double side SMD isn't possible.The only thing I am aware of that comes close are female SMD headers (see picture) that can be reflow soldered - and then you have a header on the other side that you can place through the PCB. Works perfectly. But I would prefer something that can be locked to prevent slip-off.I need to connect 3 x 2pin wires. One pair is 3.7V power, two are connecting REED sensors.Any ideas?

author: phil from seattle
author_rank: Super Contributor
timestamp: February 20, 2018, 07:16:32 am
content: Not sure what you are asking for. If you mean SMD male pin headers,they exist.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: February 20, 2018, 09:14:40 am
content: I don't get "locked", but do you mean alignment pegs or clips?My first guess would be, browse Samtec catalog and see if there's any likely parts. If they don't make anything quite right, there may be another company that does, but they'll be harder to search for, too...Tim

author: donotdespisethesnake
author_rank: Super Contributor
timestamp: February 20, 2018, 07:23:05 pm
content: I've never seen a connector that allows bottom entry and also latching, might be hard to find.How would the latch work? It would need to come through holes in the PCB I guess. You could cut a slot for a flexi cable and run it to a locking connector on the top side. Depends on current requirement.
itead or something like this - Page 1
Forum section: electronics / general

author: josip
author_rank: Regular Contributor
timestamp: February 08, 2018, 09:56:06 pm
content: My first PCB was made by itead, 2 Layer Green PCB 5cm x 5cm Max for 9.9$ and $4.61 for airmail shipping. For me quality was good, price was good, and delivery time (1 week for production and under 2 weeks in fornt of my door) was good. So I continue to work with them. Only minus was that on some boards, some vias were with uncovered / unprotected surface. Now airmail shipping is 6.61$.Unfortunately, they messed up my last order. All holes (smallest are vias 0.0157" 0.4 mm) on all boards are shifted out of center (in similar direction and center distance). Never had this problem before.Other design (2 Layer Green PCB 5cm x 5cm Max ) from the same order came with perfect centered holes.I reported this to them and they replay that they will give me back 2$ because of this error.Maybe I was just lucky with previous orders, and asking too much from this fabrication process (for that price). I know there are other similar topics here (and I read some of them), but is there are some better option regarding quality / price / full refund option? In my case 5 to 10 boards, with 2 layers, max 4 x 4 cm?

author: Rerouter
author_rank: Super Contributor
timestamp: February 11, 2018, 06:54:58 am
content: they still appear to be within tolerance, as you have not had any break outs, This is why some software packages support teardrops on pads, to reduce the risk that a breakout can brake the trace connection,All suppliers have this to different degrees, it mainly comes down to how careful the worker on that line that day aligned things between steps, you might notice your mask layer is aligned to the drill layer, however both of them disagree with the copper layer.
Prototyping complex PCBs - Page 1
Forum section: electronics / general

author: Lukas05
author_rank: Contributor
timestamp: February 08, 2018, 12:45:31 am
content: Hi guys,this is my first post on this forum, but I've been a silent reader for a long time now.English isn't my first language, but I hope you can somehow extract a meaning out of my words.To the subject:I've started a project a while ago, containing an ARM based SoC.I finished the schematic and I am ready to start the layout. The board is going to be quite complex. I am aiming at a 10 layer board with 0.1mm clearance and 0.2mm through hole VIAs. The board also needs to be impedance controlled by the manufacturer. Finding a manufacturer capable of doing this isn't a problem, but the price is.I want to get some prototype boards manufactured (5-40 pcs.) Unfortunately prototyping these kind of boards seems to be very expensive. Unfortunately I can't invest 3-6k€ in a prototype when I don't even know if i will ever make money with this project. Yes I know, thats kind of the risk that you've got to take.But to be sure I want to ask:Is there a way to get a complex prototype pcb manufactured and assembled, without loosing 3-6k€ in the worst case? (The first board wont work perfectly for sure, if at all^^) How do you prototype complex boards?Any tips are appreciated!Thanks!

author: asmi
author_rank: Super Contributor
timestamp: February 08, 2018, 01:49:58 am
content: Check this thread:https://www.eevblog.com/forum/manufacture/ourpcb-affordable-multi-layer-board-manufacturer-my-experience/This is the only shop I know of which can manufacture that kind of boards for a reasonable price.

author: rx8pilot
author_rank: Super Contributor
timestamp: February 08, 2018, 02:02:26 am
content: The short answer is:NO.While I am sure you can find some rock bottom price on PCB/ASSEMBLY etc, but that does not account for the mistakes and issues you will likely have on a 10 layer design with impedance control. At that level of complexity, it would be a risk to sell them without some validation to make sure you have some SI margins, power rails clean, and many other little things. It is entirely possible (and likely) that you could get a proto to work only to find that after making 50 pcs you have issues that are hard to explain or find.If you have to do 2 revisions of the board before you get a release level - it will cost real $$.
Am I doing this right.... seedstudio/PCB noob - Page 1
Forum section: electronics / general

author: Dreamer1
author_rank: Contributor
timestamp: February 07, 2018, 08:25:14 am
content: Hi guys, I have no idea what I'm doing.I have attempted to design a PCB.GERBERS can be found here.https://drive.google.com/open?id=1doVZ3D5MnDCO1jprnESGxAOgoDncY2EGI plan to send it to seed studio.Does it have everything I need?Sorry for the noob question - don't know who to turn to here...Thanks!

author: imidis
author_rank: Frequent Contributor
timestamp: February 07, 2018, 09:43:09 am
content: Looks to be missing a board outline.Not sure what software you are using, but on Kicad it's the edge cuts layer. (it's going to basically specify your finished board size)Scratch that, I see that in the gm4 file I think, you may need to rename it, on some sites. Usually most will let you know what is missing - file wise, they will also contact you with questions if there is something they are not sure of.

author: phil from seattle
author_rank: Super Contributor
timestamp: February 07, 2018, 07:54:35 pm
content: Go to their order page, upload your gerber and then click on the gerber viewer option. If it looks correct, you should be good to go. There is no commitment to buy at that point.
Major Help Needed  - Page 1
Forum section: electronics / general

author: milly1972
author_rank: Newbie
timestamp: February 08, 2018, 04:39:31 am
content: Hellomy name is mark and i looking for abit of help. Ok i explain my issue, A local tip is releasing H2S gases and its making the residents sick, The local papers are now on board as well as the Environment agency - who are taking readings of these said gases. " can you see were i am going with this".Ok i would like to make a unit that does similar thing, I know what i want to do and i have bought majority of the items, but i have no clue on how to make it work. I have the sensors, wifi + bluetooth module, radio module etc etc. So i wondering if theres a company that would build me the unit if i posted the items out & pay for missed items. Im also pretty sure many other people would follow and be wanting the same.Im sorry my very first post is asking for helpCheers Mark.

author: jeremy
author_rank: Super Contributor
timestamp: February 08, 2018, 04:57:04 am
content: Hi Mark,Unfortunately I cannot offer any help with your design, but I will ask: why don't you just buy an off-the-shelf unit? Obviously you are not in AUS, but a simple one sells for AU$250 here:https://www.seton.net.au/protege-zm-gas-monitor.htmlI think it would be extremely unlikely that anyone you paid to do this (or even if they did it for free) could come up with an IP67 meter for less than AU$250.

author: Mattylad
author_rank: Regular Contributor
timestamp: February 08, 2018, 07:02:35 am
content: Also, no one is going to believe the readings you get from a DIY unit.Maybe renting one would help you?Whinney hill by chance?
Adafruit Machine line - good article  - but I have a question - Page 1
Forum section: electronics / general

author: mwilliams03
author_rank: Newbie
timestamp: January 31, 2018, 12:51:19 am
content: Adafruit posted a good article about their machine line;https://blog.adafruit.com/2018/01/22/adafruit-machine-line/However, I have a question about what they use for hand soldering;"Nordson Select KISS-102 selective soldering machine – Hand soldering large batches of thru-hole components can be a time consuming task. In order to cut down on the amount of time needed to complete soldering operations we generally process boards through this machine which allows us to automate the soldering process with precision. Solder joints produced through this process are far more uniform in nature than when done by hand."This is the image associated with it;I am confused with what is actually happening here.. .could please someone explain?

author: EEVblog
author_rank: Unknown
timestamp: January 31, 2018, 12:55:12 am
content: It's a molten solder wave tip.Works just like wave soldering an entire board except you have a fine head on an X-Y motor that can solder individual or groups of through hole pins at once, hence "selective". e.g. a header connector.

author: mwilliams03
author_rank: Newbie
timestamp: January 31, 2018, 02:55:35 am
content: thanks! i didn't even know these existed

author: mairo
author_rank: Unknown
timestamp: January 31, 2018, 06:48:53 am
content: and the head/nozzle size also can vary (similar to having different soldering iron tips) based on the size of the parts you were soldering. These machines also have inbuilt preheaters to warm up the board, as well as flux spraying mechanism (it will first spray the flux to the area/joint that will be soldered); more advanced machines also integrate cameras for post reflow/solder check. KISS, ERSA are some manufacturers of such machines.
Company that makes custom leads wires (not USA) - Page 1
Forum section: electronics / general

author: Jeroen3
author_rank: Super Contributor
timestamp: January 12, 2018, 10:13:29 am
content: I'm trying to find a company that can make small pieces of wire of medium quantity (1000's).For reference, 1.5mm2 wires ~60mm with one m4 ring and one end tinned.All I can find are USA based companies or sellers of the machines. Google is letting me down here.

author: Mr. Scram
author_rank: Super Contributor
timestamp: January 12, 2018, 10:37:18 am
content: Quote from: Jeroen3 on January 12, 2018, 10:13:29 amDirty Cables perhaps?https://dirtypcbs.com/store/cables

author: Ferisoda
author_rank: Newbie
timestamp: January 30, 2018, 08:03:18 am
content: Can this knowledge be learned on their own?

author: Jeroen3
author_rank: Super Contributor
timestamp: January 30, 2018, 08:26:02 am
content: Meanwhile I've asked our main supplier, who also have industrial cabinet assembly service.I asked for 500 pcs of each various color and AWG around ~60mm with A: ring M4/5 B:tinned, they've quoted around €0.80-0.90 per wire.Total 7 different assemblies 3500 wires for €3k.They didn't want to tell if they owned the equipment for this, or asked another company.

author: Corporate666
author_rank: Unknown
timestamp: January 30, 2018, 08:28:29 am
content: Quote from: Jeroen3 on January 12, 2018, 10:13:29 amI use JKJ Conn - have been very happy with their pricing and quality so far (have placed 4 orders, about 15,000pcs so far).http://www.jkjconn.com/products.asp?classid=2That's the link for some of their wires/harnesses but they do all sorts of custom work with whatever kind of wire and connector you want.I deal with Rachel Yuan there.... rachel@jkjconn.com, she's been good in terms of fast replies, quotes, etc.

author: The Soulman
author_rank: Super Contributor
timestamp: January 30, 2018, 08:51:24 am
content: Worth a shot:http://www.vanoostvoorn.nl/cable-workshop