Author Topic: Professional assembly mishaps  (Read 27676 times)

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Offline james_s

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Re: Professional assembly mishaps
« Reply #100 on: December 19, 2017, 06:44:19 pm »
That Dilbert cartoon is hilarious, that mirrors my experience almost exactly.
 

Offline Leo BodnarTopic starter

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Re: Professional assembly mishaps
« Reply #101 on: December 27, 2017, 10:24:00 am »
Few more bingos from Birmingham.
 

Online wraper

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Re: Professional assembly mishaps
« Reply #102 on: December 27, 2017, 11:30:53 am »
Few more bingos from Birmingham.
I wonder how did they get it. They would need to either put those through reflow process with connectors inserted or stop within wave soldering machine for prolonged time. Solder joints on connector pins don't look nice as well, look like blobs of solder.
 

Online coppice

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Re: Professional assembly mishaps
« Reply #103 on: December 27, 2017, 12:07:16 pm »
These are all from ISO9000 certified UK companies.
All that says is they should be offering the same defect rate consistently to all their customers.
 

Offline Mr. Scram

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Re: Professional assembly mishaps
« Reply #104 on: December 27, 2017, 01:52:42 pm »
Few more bingos from Birmingham.
Aren't those just the wrong USB connectors? Maybe these simply weren't connectors intended for reflow. The pin headers look fine.
 

Online wraper

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Re: Professional assembly mishaps
« Reply #105 on: December 27, 2017, 01:58:24 pm »
Few more bingos from Birmingham.
Aren't those just the wrong USB connectors? Maybe these simply weren't connectors intended for reflow. The pin headers look fine.
Why would they need to be intended for reflow?
 

Online JPortici

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Re: Professional assembly mishaps
« Reply #106 on: December 27, 2017, 02:00:57 pm »
a recent adventure with wave soldering: in this board a big automotive connector is wave soldered.
i am programming and testing the latest batch, one board won't program.. strange. then i see the smoke.
It turns out that the external 5V line is shorted to ground, the smoke came from a series resistor so the current wasn't high enough to trigger OCP but high enough to excheed the power rating and burn the resistor.

a good half hour spent inspecting the board and then i see it, a splash of solder on the inside of the connector :palm: and the only short was between +5V and GND, of course.
 

Online coppice

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Re: Professional assembly mishaps
« Reply #107 on: December 27, 2017, 02:05:19 pm »
Few more bingos from Birmingham.
Aren't those just the wrong USB connectors? Maybe these simply weren't connectors intended for reflow. The pin headers look fine.
Why would they need to be intended for reflow?
Things intended for reflow need to be built to tolerate the temperatures involved in reflow. Some things designed for reflow with leaded solder can't take the higher temperatures involved in lead free reflow.

Many through hole connectors can't tolerate reflow, as they were designed for wave soldering. Wave soldering keeps a lot of the heat away from the side of the board with the plastic parts.
 

Offline Leo BodnarTopic starter

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Re: Professional assembly mishaps
« Reply #108 on: December 27, 2017, 02:11:12 pm »
coppice, PCBs that have both type of components are made in two stages.
These are PTH connectors.  They are not intended for reflow.

Few other jobbies from the same gentlemen.  Unfortunately, we figured them out too late to stop the destruction.

 

Online wraper

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Re: Professional assembly mishaps
« Reply #109 on: December 27, 2017, 02:32:40 pm »
Things intended for reflow need to be built to tolerate the temperatures involved in reflow. Some things designed for reflow with leaded solder can't take the higher temperatures involved in lead free reflow.

Many through hole connectors can't tolerate reflow, as they were designed for wave soldering. Wave soldering keeps a lot of the heat away from the side of the board with the plastic parts.
Trough hole parts = not intended for reflow. Sometimes reflow can be done to avoid additional production stage but this is a special case when components need verification they can withstand it, not how things are done normally. Also there is so much solder on the solder joints it's basically impossible that was reflow soldered. Not enough solder to fill the hole is actually a big problem if you reflow solder TH components.
 

Online coppice

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Re: Professional assembly mishaps
« Reply #110 on: December 27, 2017, 02:38:40 pm »
Trough hole parts = not intended for reflow.
That's not strictly true. Reflow is not the ideal (or cheapest) way to solder through hole parts. However, many through hole connectors and heavy inductors are designed to tolerate the temperatures involved in reflow, so the board can be stuffed in one go, and all the parts will be safe during the reflow step(s).
 

Offline fcb

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Re: Professional assembly mishaps
« Reply #111 on: December 28, 2017, 11:34:37 am »
I get that they might have used the wrong wave solder settings (speed), or that the USB sockets chosen/substituted aren't upto it and that the wave can easily move those long cage-clamps (or they weren't seated correctly etc..).

What I can't get my head round is that they still sent them out - their QC must be non-existent.
https://electron.plus Power Analysers, VI Signature Testers, Voltage References, Picoammeters, Curve Tracers.
 

Offline julianhigginson

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Re: Professional assembly mishaps
« Reply #112 on: December 28, 2017, 11:44:34 am »
every package from these guys must have you jumping up and down with excited anticipation at what they have stuffed up this time!
 

Offline Gribo

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Re: Professional assembly mishaps
« Reply #113 on: December 28, 2017, 02:39:06 pm »
Quote
What I can't get my head round is that they still sent them out - their QC must be non-existent.

Maybe it was approved by blind hamsters?
I am available for freelance work.
 

Offline nanofrog

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Re: Professional assembly mishaps
« Reply #114 on: December 29, 2017, 09:58:08 am »
Quote
What I can't get my head round is that they still sent them out - their QC must be non-existent.

Maybe it was approved by blind hamsters?
Oi! Stop talking about my critters.   :o

Kidding. Mine's a rather pudgy lab cat (originally named Oliver after Oliver Twist, but has since been properly renamed Porkins).   :o  >:D
 

Offline capt bullshot

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Re: Professional assembly mishaps
« Reply #115 on: December 17, 2018, 09:32:11 am »
A rather smallish mishap:

Safety devices hinder evolution
 
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Offline bd139

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Re: Professional assembly mishaps
« Reply #116 on: December 17, 2018, 09:36:22 am »
How the hell did that happen  :-DD
 

Offline Rerouter

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Re: Professional assembly mishaps
« Reply #117 on: December 17, 2018, 09:44:11 am »
I'm more impressed that the connectors look so unaffected, the USB socket has had so much solder pour in that its leaking out the back corner yet the ethernet and general connector are un-melted to my eyes.
 

Offline capt bullshot

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Re: Professional assembly mishaps
« Reply #118 on: December 17, 2018, 09:58:49 am »
I'm more impressed that the connectors look so unaffected, the USB socket has had so much solder pour in that its leaking out the back corner yet the ethernet and general connector are un-melted to my eyes.

It's difficult to see on that photo, the solder has found its way in between the USB and eth socket, not through them. I've heard someone mumbling about the hand operated mini wave soldering machine ...
Safety devices hinder evolution
 

Offline SeanB

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Re: Professional assembly mishaps
« Reply #119 on: December 17, 2018, 09:59:03 am »
Went Under the wave, not on the top of it.......
 

Offline tristan PCB

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Re: Professional assembly mishaps
« Reply #120 on: December 17, 2018, 11:20:47 am »
I really “admire” the professional manufacturing level
 

Offline hermit

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Re: Professional assembly mishaps
« Reply #121 on: December 17, 2018, 01:07:14 pm »
I'm more impressed that the connectors look so unaffected, the USB socket has had so much solder pour in that its leaking out the back corner yet the ethernet and general connector are un-melted to my eyes.

It's difficult to see on that photo, the solder has found its way in between the USB and eth socket, not through them. I've heard someone mumbling about the hand operated mini wave soldering machine ...
Hand operated mini tsunami soldering machine.....
 

Offline bd139

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Re: Professional assembly mishaps
« Reply #122 on: December 17, 2018, 01:10:22 pm »
Someone put a drunk T1000 in it
 

Offline CJay

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Re: Professional assembly mishaps
« Reply #123 on: December 17, 2018, 03:01:54 pm »
A rather smallish mishap:



Pfft, bit of solderwick and a steady hand, she'll be right...
 

Offline julianhigginson

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Re: Professional assembly mishaps
« Reply #124 on: December 17, 2018, 08:16:02 pm »
How on earth did that get packed and sent?
 


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