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The best way to erase flux from the golden fingers?

#3254

The best way to erase flux from the golden fingers? | 18 August, 2000

Hello sirs, Would you kindly provide me the best way to erase the flux attached on the golden fingers? What we can do now is to use the pencil eraser to remove the flux.

Thanks in advance.

Gyver

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#3255

Re: The best way to erase flux from the golden fingers? | 21 August, 2000

Hey Gyver: Oooow, using a pencil eraser has to take time. I would hate to be the person responding to your customer trying to explain the pencil eraser shreds accidentally left on the board.

Awww, just spritz it with DI water and wipe it off with a Kleenex. ;-)

Seriously, consider taking a couple of different angles, which are: 1 Stop putting flux on your gold fingers by: * Selecting a flux that doesn�t splatter in your application. Not all NC pastes are created splaterifically equal. * Slowing down the ramps on your profile to reduce some of the flux spraying. * Limiting the peak reflow temperature. * Increasing soak time. * Decreasing the slope of the ramp during soak. This is contrary to the recommended profile for many "modern" pastes that basically have one ramp rate to reflow and one cooling ramp. 2 Consider alternate approaches to removing the flux, such as: * Some NC fluxes are cleanable. Talk to your paste supplier technical types about selecting a proper solvent for cleaning your gold fingers. * Protect the gold fingers before reflow. Look at past threads in the SMTnet archives on protecting gold fingers from solder splatter. 3 Reduce the cost of your current process * Buy pencils by shopping at Wal-Mart, rather than Staples. * Use a uV doped flux to make it easier to pick-up [see] the flux splats.

Please tell me why you use gold fingers on your boards.

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#3256

Re: The best way to erase flux from the golden fingers? | 1 September, 2000

Hello Dave, The gold fingers are on graphic cards. What did you mean by DI water? I need to know that very soon, thanks a lot!

Sincerely,

Gyver

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#3257

Re: The best way to erase flux from the golden fingers? | 2 September, 2000

Hey Gyver: I was just spoofin' ya about the deionized water (DI). Water of any type will probably make your solder connections go white.

I posted your question to Dr. Lee on the latest OnBoard Forum. I suggest you check his responses. I short he says change your profile or your flux.

So, why do you put the gold fingers on your graphic cards?

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#3258

Re: The best way to erase flux from the golden fingers? | 2 September, 2000

Yanno, I just thought of an addition to #3 above.

Back in the ol' days (before computer drawing) there were rooms full of people, generally guys (with plastic pocket protectors holding colored pens and ... ) leaning on drawing boards, doing whatever they did. Anywho, they used motor powered erasers.

May be you could find one of those to improve your ability to scrub the fluxes from your gold fingers.

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#3259

Re: The best way to erase flux from the golden fingers? | 5 September, 2000

Hi Dave, Thanks for your great help! Well, gold fingers are always on any kind of cards, right? Or you were confused by my poor English...sorry!:-( Now we are going to implement some kind of method to prevent the gold fingers from being contaminated by flux. Hope this can work! Thanks again!

Regards,

Gyver

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#3260

Re: The best way to erase flux from the golden fingers? | 5 September, 2000

Yeh, gold fingers are always on any kind of cards. I just can't figure-out why.

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