Hacking DSONE clones appear to be available for purchase

FAST6191

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Reflow should cure slight misalignment. It is actually quite amusing to watch surface mount and BGA stuff align itself when soldering. If it is bridging a pin or on the next one over that is a different matter and will see you have to remove and reseat.
 

notrea11y

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@FAST6191 I've seen that 'realigning' countless times on several repair-shop videos on YT.
Aside from the "physical basis" for it, I wonder if that phenomenon has a name ?
 

FAST6191

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I don't know actually.
Seen plenty of people who are otherwise phenomenal electrical engineers discuss it when teaching surface mount soldering but all I can think of just note it is somewhat self aligning (assuming you did not stick the chip down*, hold it down too hard or not get it all molten at once) and leave it at that.
I can cover the physical basis for it if you wanted, though would be just as easy to say "go look up the usual discussion of lowest possible energy state for surface area, usually done for bubbles aka why are bubbles round?" that they teach to 16-undergrad in physics/engineering as it is the same thing really.
Many years ago I did a very short bit with exotic solders and wetting of them/getting them to have nice wetting like good old lead-tin (can be done, expensive though) but never really had to categorise this alignment as much as flowing into a more mechanical type solder join.

*dab of superglue under a particularly annoying chip or component is done occasionally if dab of flux is not available or not working.
 
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Sophie-bear

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Reflow should cure slight misalignment. It is actually quite amusing to watch surface mount and BGA stuff align itself when soldering. If it is bridging a pin or on the next one over that is a different matter and will see you have to remove and reseat.
Ended up bricking the card somehow from trying too many times (maybe burnt something?). I don't care much, easy come easy go and all. But yeah, I removed the SRAM chip and there were some bridging issues going on. If I cared more or had the skill to fix it, I would, but it's honestly not worth the time or effort.
 

notrea11y

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I don't know actually.
Seen plenty of people who are otherwise phenomenal electrical engineers discuss it when teaching surface mount soldering but all I can think of just note it is somewhat self aligning (assuming you did not stick the chip down*, hold it down too hard or not get it all molten at once) and leave it at that.
I can cover the physical basis for it if you wanted, though would be just as easy to say "go look up the usual discussion of lowest possible energy state for surface area, usually done for bubbles aka why are bubbles round?" that they teach to 16-undergrad in physics/engineering as it is the same thing really.
Many years ago I did a very short bit with exotic solders and wetting of them/getting them to have nice wetting like good old lead-tin (can be done, expensive though) but never really had to categorise this alignment as much as flowing into a more mechanical type solder join.

*dab of superglue under a particularly annoying chip or component is done occasionally if dab of flux is not available or not working.
The basics would suffice.
(Maybe put em in a Spoiler so our temp friends here don't flee from this lil physics discourse)

Superglue in combination with chips :blink:.. Huh.
 
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FAST6191

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If your hot air is blowing your chips, connectors or whatever around then a dab of superglue underneath can get it to hold while you sort the pins out (or enough pins out). Most will prefer some sticky flux or something that will wash out but at the same time keep it close enough and it will not short anything out, and can even protect against water ingress a bit. Bonus is the solvent used to dissolve superglue is acetone which most electrical types have by the barrel anyway.

On self aligning solder then it really is the basic surface tension/why are bubbles round* thing most schools in the English speaking world and anything that competes with it teach their at least slightly interested in physics students, and definitely those that take it up in earnest. Here the board and the chip leg (or pad as the case may be) act as two plates so you get into that regime rather than bubble in a vacuum or simple surface film of some examples but it is ultimately the same idea. Or going the other way the effective trapezoid that unaligned solder forms is a higher energy setup as far as surface area and tension is concerned than a more simple square profile that the properly aligned setup will be so that nice law of thermodynamics that says the lowest energy arrangement/maximum disorder state will be taken which is enough to drag a few grams of chip along for the ride (and as going the other way starts to form a trapezoid profile but in the other direction it is not going to get far there and will pretty much settle in quickly) when multiplied by enough pins that the surface area is within the same order of magnitude.

*usually done along the lines of imagine a molecule, it wants to be at as low an energy as possible and so do its neighbours, one randomly jutting out (as might be the case in a corner) has more energy so it will take the lowest point and so will its neighbours all the way down the line, the sphere then being the natural result of that one as every direction then gets to be as low as it can be overall. Just because the liquid is now a molten mixture of lead and tin (or something less wondrous in the case of modern electronics) does not mean thermodynamics and by extension fluid mechanics don't get obeyed. Might be hot compared to the average temperature of the universe but same applies to liquid water and nobody seems to complain when contemplating that. Usually comes with a whole bunch more maths, and if it is a chemistry side of things teaching it then bond angles will probably have preceded it, if more metals then unlucky as you will probably get bogged down in vector maths at this point (see stacking faults), but I don't think it particularly enlightens much in this (though the iteration to arrive at low energy states is not bad).
 

fli_guy84

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Just bought one for fun. Will get it in about a week. Hope it's not a dud.

Edit 1:
  1. Got my unit a few weeks ago and it works perfectly. No issue at all.
  2. I ordered another one last week and it arrived today. Unfortunately, it has the PSRAM error. Gonna try to reflow the IC tomorrow and see what happens.

Edit 2:
Placed the one with PSRAM error into a infrared reflow oven and now the issue is gone. Got 2 good units now.
 
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ecto

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Edit 2:
Placed the one with PSRAM error into a infrared reflow oven and now the issue is gone. Got 2 good units now.
My card was working when I got it, but now I get a psram error.
What temperature did you choose for the reflow and what flux have you used?
I will try to rework on a hotplate.
 

fli_guy84

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My card was working when I got it, but now I get a psram error.
What temperature did you choose for the reflow and what flux have you used?
I will try to rework on a hotplate.
I just used the default profile on the oven, which I think follows the J-STD-020 standard. For flux, I used Chipquick syringe. I lined up the flow at all the edges before putting the cart into the oven.
 
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