🚀 go-pugleaf

On Thu, 23 Jul 2009 21:15:26 -0700, "JosephKK"<quiettechblue@yahoo.com>
wrote:

>On Thu, 23 Jul 2009 23:08:51 +1000, "Shaun" <not.today@go.away.au>
>wrote:
>
>>
>>"Tim Williams" <tmoranwms@charter.net> wrote in message 
>>news:r1Y9m.18834$eS5.11501@newsfe25.iad...
>>> "Shaun" <not.today@go.away.au> wrote in message 
>>> news:4a684505$0$2227$afc38c87@news.optusnet.com.au...
>>>> It might be possible but I can't think of any non-conductive material 
>>>> that could be layered thin enough and still go through a wave solder 
>>>> machine.
>>>
>>> Um, so what about the stuff they put on resistors?
>>>
>>> Ink is incredibly thin stuff.
>>>
>>    I didn't think an ink would withstand the the temperature (thinking 
>>along the lines of markings either being etchings or printed then 
>>encapsulated) but I have found an ink that could withstand the temperature, 
>>can even be used on ceramic materials, only problem is it has the be air 
>>brush stenciled, manufacture states it's not suitable for stamp or roller 
>>application.
>>    Okay so I've got no idea why such an ink isn't used to directly print to 
>>the capacitor,
>>
>>Shaun 
>>
>
>Come to think of it, wave solder is more of a through hole process.
>The modern process is reflow.  Wave solder does not pay well with SMD
>parts on both sides, reflow does.

  Originally, SMD parts were used along with thru hole. The "solder
side", as it was called, had thermal cure glue at all the SMD locations,
and the SMD parts get placed  with no solder paste at all, and then the
curing oven bakes them in place. Then the boards went to a push line or
auto-inserter and the thru hole parts get added, being careful with the
solder side attached-but-not-yet-soldered parts.  During wave solder, the
PCB gets passed over a flux bubbler.  Next thing you know, the thru hole
and the bottom side SMD parts are soldered.