Clean Off Your Flux!!

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Fred
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Clean Off Your Flux!!

Post by Fred »

I got "fluxed" by this today, among other things. When assembling hardware, even if temporarily, clean off the flux!

I put my FredStim together a year ago, it stopped working about a month ago. I needed it today, and fixed it. Fix: Cleaning with alcohol, toothbrush, ultrasonic cleaner.

I know Sean got "fluxed" by flux too, recently. Spudmn got "fluxed" by flux a while back when it ate his FT232R chip. Many people get "fluxed" by flux. Clean off your flux, before it "fluxs" you too.

Flux is conductive, especially in a humid environment. It's fairly dry when first assembled due to the heat, but after time, it changes and starts conducting and ruining your signals or hardware. It can even dissolve your hardware in extreme cases, permanently damaging it.

This warning brought to you by a fellow victim, "fluxed" by flux. Feel free to share stories of your experiences getting "fluxed" by flux.

Fred.
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ivan141
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Re: Clean Off Your Flux!!

Post by ivan141 »

I always have a bottle of PCC nearby for immediate cleanup after soldering (printed circuit cleaner).
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tpsretard
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Re: Clean Off Your Flux!!

Post by tpsretard »

i had this problem a while back.

A megasquirt not built by me, but tuned in a rally car.
Everything went really strange, pulled it out tested things that were just odd. I figured it out after a meeter prob slipped off the terminal and was still frikken reading. looked everywhere in the service park, many paint brushes, many tooth brushes.. but no alcohol.

Finally desperate i said well, it is "Fluxed" already, cant make it worst. Out with a can of non chlorinated brake cleaner. Blow off with an air gun. 2 swings and it was running again. we actually one the rally.. lol

after that i always de flux everything even it is a temp fix..
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AiToR51
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Re: Clean Off Your Flux!!

Post by AiToR51 »

oh, that happened to me a month ago. I was having a lot of misfirings without any cause. Until I revised the ECU and saw a zone with white spots between transistors legs. (I had used flux near to one months before that fail..), cleaned it and misfires gone :lol2:
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Fred
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Re: Clean Off Your Flux!!

Post by Fred »

I put the SMD parts on an 0.4-alpha Jaguar for piimae tonight and post testing was soaking it in alcohol ready to scrub it and the flux became very visible, so here it is in full resolution (excessive). The brown bits are flux, as are the white spots. There is also some lense flare, that's not flux...:

Image
DIYEFI.org - where Open Source means Open Source, and Free means Freedom
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