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   ✧✦Catherine✦✧ (whitequark@mastodon.social)'s status on Friday, 06-Jun-2025 12:58:22 JST ✧✦Catherine✦✧

   this is the first IC i reballed successfully (as far as i recall)

   rate me?

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     ✧✦Catherine✦✧ (whitequark@mastodon.social)'s status on Friday, 06-Jun-2025 13:23:02 JST ✧✦Catherine✦✧

     in reply to

     • Graham Sutherland / Polynomial

     @gsuberland oh holy shit, eagle eye! thank you, i took it off the preheater and removed, there was indeed a solder ball

     the ones which have low solder quantity (esp the right one) aren't doing anything according to the bitstream disassembly, so i decided to leave them as-is

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     Graham Sutherland / Polynomial (gsuberland@chaos.social)'s status on Friday, 06-Jun-2025 13:23:03 JST Graham Sutherland / Polynomial

     in reply to

     @whitequark decent job!

     spotted a couple that might need some extra attention. the far left and right ones are probably ok (low solder quantity), but that middle one looks like it has an extra solder ball stuck to it and you might get a short.

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     ✧✦Catherine✦✧ (whitequark@mastodon.social)'s status on Friday, 06-Jun-2025 13:24:13 JST ✧✦Catherine✦✧

     in reply to

     • Graham Sutherland / Polynomial

     @gsuberland the key lesson i learned to get it to be this good was that (a) you use a stencil with paste, not loose balls that are fuckin impossible to get to stay in place and (b) you have to get the IC to be *really* level and flat wrt the stencil in the jig, or you'll push paste underneath it and end up with a mess of shorts and blobs

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     Richard Hendricks (hendric@astronomy.city)'s status on Friday, 06-Jun-2025 13:24:34 JST Richard Hendricks

     in reply to

     @whitequark I rate you 624 out of 625!

     Funny story, back at ye olde semiconductor company, a customer's ops team heard something funny in one of our vac packs. They did medical devices including x-rays, and sent us an x-ray picture with a big angry red circle around the loose solder balls in the pack. Uh, oops!

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     ✧✦Catherine✦✧ (whitequark@mastodon.social)'s status on Friday, 06-Jun-2025 13:25:05 JST ✧✦Catherine✦✧

     in reply to

     • Richard Hendricks

     @hendric what's a vac pack?

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     ✧✦Catherine✦✧ (whitequark@mastodon.social)'s status on Friday, 06-Jun-2025 13:44:03 JST ✧✦Catherine✦✧

     in reply to

     • Graham Sutherland / Polynomial

     @gsuberland i have one of those... ish? it has a spout but i don't think it works if the stencil is 20 rows oversized

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     Graham Sutherland / Polynomial (gsuberland@chaos.social)'s status on Friday, 06-Jun-2025 13:44:04 JST Graham Sutherland / Polynomial

     in reply to

     @whitequark doing the solder balls by hand is an extreme headache, but you can get BGA reballing frames reasonably cheaply where you clamp the part in the lower section after applying a little flux, clamp the stencil in the upper section, they're spring loaded so it presses the stencil down, then you pour a ton of solder balls into the top and roll them around, then it has a little channel in the corner where you can tip the excess balls back into the container. pretty painless.

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     ✧✦Catherine✦✧ (whitequark@mastodon.social)'s status on Friday, 06-Jun-2025 13:47:18 JST ✧✦Catherine✦✧

     in reply to

     • Graham Sutherland / Polynomial

     @gsuberland ... oh, so simple and effective

     anyway i found these impossible to use with the loose balls because the balls would not stay in place

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     Graham Sutherland / Polynomial (gsuberland@chaos.social)'s status on Friday, 06-Jun-2025 13:47:20 JST Graham Sutherland / Polynomial

     in reply to

     @whitequark ah yeah I usually kapton tape the stencil to mask off the extra holes.

     I have a very similar frame, and a fancier one somewhere which I can't currently find.

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     ✧✦Catherine✦✧ (whitequark@mastodon.social)'s status on Friday, 06-Jun-2025 13:49:06 JST ✧✦Catherine✦✧

     in reply to

     • Buttered Jorts
     • Graham Sutherland / Polynomial

     @ajn142 @gsuberland no _i_ am a dummy here lol

   • Embed this notice
     Buttered Jorts (ajn142@infosec.exchange)'s status on Friday, 06-Jun-2025 13:49:07 JST Buttered Jorts

     in reply to

     • Graham Sutherland / Polynomial

     @whitequark @gsuberland I’m a dummy but could you use painter’s tape or kapton to block the rows not in use?

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     ✧✦Catherine✦✧ (whitequark@mastodon.social)'s status on Friday, 06-Jun-2025 13:53:06 JST ✧✦Catherine✦✧

     in reply to

     • Graham Sutherland / Polynomial

     @gsuberland tried that, it ends up clogging the holes and lifting the balls with the stencil

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     Graham Sutherland / Polynomial (gsuberland@chaos.social)'s status on Friday, 06-Jun-2025 13:53:08 JST Graham Sutherland / Polynomial

     in reply to

     @whitequark flux paste helps a ton with that.

     also found my fancier one.

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     ✧✦Catherine✦✧ (whitequark@mastodon.social)'s status on Friday, 06-Jun-2025 14:26:46 JST ✧✦Catherine✦✧

     in reply to

     @gsuberland done that before and the outcome is that the stencil massively warps therefore shifting the balls quite a lot

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     Graham Sutherland / Polynomial (gsuberland@chaos.social)'s status on Friday, 06-Jun-2025 14:26:47 JST Graham Sutherland / Polynomial

     in reply to

     @whitequark try heating it directly in the frame, with the stencil in place. the solder balls will preferentially stick to the pads, not the stencil.

   • Embed this notice
     ✧✦Catherine✦✧ (whitequark@mastodon.social)'s status on Friday, 06-Jun-2025 14:59:35 JST ✧✦Catherine✦✧

     in reply to

     i have soldered it back and...

     it works :D :D :D

     (after reflowing it the second time, because this package has a chonky heatsink and it's really difficult to work with)

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     ✧✦Catherine✦✧ (whitequark@mastodon.social)'s status on Friday, 06-Jun-2025 16:12:52 JST ✧✦Catherine✦✧

     in reply to

     • amy

     @amy thanks ^^

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     amy (amy@fedi.amy.mov)'s status on Friday, 06-Jun-2025 16:12:56 JST amy

     in reply to

     @whitequark@mastodon.social nice balls