Flux

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Andy Le Blanc
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Flux

Post by Andy Le Blanc »

With RoHS coming, I've been looking to complete a compliant BOM for any
product to be sold outside of the lower 48. This is pretty easy for a basic amp.
The available solder alloy is SAC305. What is the better flux type to use with this alloy for hand assembly?
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Kregg
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Re: Flux

Post by Kregg »

I've always been under the impression that flux is a no no in electronic circuits, because it sets up electrolysis which leads to corrosion and connection failures.
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VacuumVoodoo
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Re: Flux

Post by VacuumVoodoo »

Use halogen free "no clean" flux. Or better yet use solder alloy with flux in it already.
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Jana
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Re: Flux

Post by Jana »

There is a lengthy discussion here on lead free solder:

http://www.fenderforum.com/forum.html?d ... 2016:51:14
Andy Le Blanc
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Location: central Maine

Re: Flux

Post by Andy Le Blanc »

I've had to repair circuits where somebody used the wrong solder and flux type.
Lead rosin core solder has been a mainstay for such a long time. It is very
convenient. Some basic questions come to mind when changing alloys.
Flux, temperature, wetting. Still here in The US the 63/37 lead alloy is readily
available and one third the price. I don't want to be stuck having to make two
product lines or unnecessary investments, because the US cant get the lead
out of it's butt.
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Structo
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Re: Flux

Post by Structo »

I had to touch up some solder joints on a lead free amp.

I originally just tried to re-flow the solder on the socket pins.

Man, that stuff turned into a grey crusty joint.

So I tried adding some 63/37 solder to it.....

Must be a trick to touching up lead free solder joints.
:?
Tom

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drz400
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Re: Flux

Post by drz400 »

Structo wrote:I had to touch up some solder joints on a lead free amp.

I originally just tried to re-flow the solder on the socket pins.

Man, that stuff turned into a grey crusty joint.

So I tried adding some 63/37 solder to it.....

Must be a trick to touching up lead free solder joints.
:?
Some will tell you that you can not mix the two. They eventually try to migrate, break down and will cause snap crackle pops or so I've heard.
http://www.indium.com/blogs/Dr-Lasky-Bl ... 17,12,408/
Andy Le Blanc
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Location: central Maine

Re: Flux

Post by Andy Le Blanc »

I've been digging and found that these alloy's have a higher melting point.
The familiar lead solder melts around something like 180c, and the lead free
melts around 217c. The issue here is the assumption that your soldering iron
is compatible. My old Weller won't cut it. I'm gonna have to step up to
an 85w work station and mind the temp setting. That puts a crimp on the
home DIY budget. There's gonna be boundary in the market place, it will be
harder for the beginner to over come.
lazymaryamps
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