Author Topic: 'just reflow it', or how not to do it  (Read 3557 times)

0 Members and 1 Guest are viewing this topic.

Offline Rasz

  • Super Contributor
  • ***
  • Posts: 2314
  • Country: 00
    • My random blog.
'just reflow it', or how not to do it
« on: November 26, 2014, 12:21:10 pm »
I told someone to try and reflow bad solder joints, this is what happened. I call this reverse dunning kruger - I always assume people know basic stuff, turns out its only basic for a practitioner :/


Who logs in to gdm? Not I, said the duck.
My fireplace is on fire, but in all the wrong places.
 

Offline Kjelt

  • Super Contributor
  • ***
  • Posts: 5767
  • Country: nl
Re: 'just reflow it', or how not to do it
« Reply #1 on: November 26, 2014, 12:55:06 pm »
Well those are not easy chips to say "just reflow".
Only thing that would have a chance is use flux and put it in a really good reflow oven.
What did he do to tombstone it, put a heatgun on one side?
 

Online Monkeh

  • Super Contributor
  • ***
  • Posts: 6095
  • Country: gb
Re: 'just reflow it', or how not to do it
« Reply #2 on: November 26, 2014, 01:00:09 pm »
I suspect that sticker 'helped'.
 

Offline DmitryL

  • Regular Contributor
  • *
  • Posts: 235
  • Country: gb
Re: 'just reflow it', or how not to do it
« Reply #3 on: November 26, 2014, 01:40:03 pm »
I told someone to try and reflow bad solder joints, this is what happened. I call this reverse dunning kruger - I always assume people know basic stuff, turns out its only basic for a practitioner :/

There is a proverb in Russian, saying something like "If a god would give a crystal penis to a fool, that fool will break it into pieces and cut his hands as well "
 

Offline idpromnut

  • Supporter
  • ****
  • Posts: 613
  • Country: ca
Re: 'just reflow it', or how not to do it
« Reply #4 on: November 26, 2014, 05:38:07 pm »
Is it just me, or are all of those ICs also cracked in half through the middle?
 

Offline senso

  • Frequent Contributor
  • **
  • Posts: 897
  • Country: pt
    • My AVR tutorials
Re: 'just reflow it', or how not to do it
« Reply #5 on: November 26, 2014, 05:58:30 pm »
Due to the support you used there is a thermal gradient across the board, and the sticker wrinkled and seem to have pulled the chips.
 

Offline Rasz

  • Super Contributor
  • ***
  • Posts: 2314
  • Country: 00
    • My random blog.
Re: 'just reflow it', or how not to do it
« Reply #6 on: November 27, 2014, 03:01:12 pm »
Due to the support you used there is a thermal gradient across the board, and the sticker wrinkled and seem to have pulled the chips.

1 wasnt me, just a dude on a computer forum I tried to help
2 support looks as good as you gonna get, from the looks of it it is a cake oven


there are no cracks, this module has 8 chips (or maybe 16, no picture of the other side)


It was totally my fault  :palm: . I told the guy to support pcb on the corners so chips dont touch anything, I forgot/didnt occur to me some pc memory modules have those stupid stickers across multiple chips. This is one of those things you do automatically without thinking when reworking smd (glue, stickers, plastic, spacers).
Who logs in to gdm? Not I, said the duck.
My fireplace is on fire, but in all the wrong places.
 

Offline wagon

  • Frequent Contributor
  • **
  • Posts: 290
  • Country: au
Re: 'just reflow it', or how not to do it
« Reply #7 on: November 29, 2014, 04:48:21 am »
I've reflowed stuff like that with just a bit of flux and a heatgun with a very small nozzle.  I do one side, let it rest, do the other.  Works well.
Hiding from the missus, she doesn't understand.
 


Share me

Digg  Facebook  SlashDot  Delicious  Technorati  Twitter  Google  Yahoo
Smf