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Old 10-30-2018, 07:49 AM   #1
stj
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Exclamation how not to desolder

https://www.youtube.com/watch?v=6hGFXWGENfs

i needed to post this because this fool is blaming the tool for his lack of knowledge!

problems/mistakes:

1: using solder - you never use solder because the flux enables the solder to stick in the tool.
2: using too much heat - he's dry-jointing the solder as soon as it melts.
3: not pushing the trigger long enough - you need to clear the solder from the tool as well as the pcb.
4: desoldering downwards - your fighting gravity and molten solder can drop back down onto the pcb.
5: removing the splash-plate from the collector - it will make it block the pump much faster
6: blaming the tool for the other 5 mistakes!!

oh yea, 7 - he complains that it takes forever to cool down.
that's thermal-mass, and it's a good thing.

Last edited by stj; 10-30-2018 at 07:50 AM..
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Old 10-30-2018, 04:50 PM   #2
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Default Re: how not to desolder

OMG savage! His technique is so bad, he must have resoldered each joint 20 times and like a gorilla presses down so hard with the desoldering gun he damages things. Just keep heating it LOL.
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Old 10-30-2018, 10:20 PM   #3
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Default Re: how not to desolder

haha it's like a gorilla with a pencil trying to write his name. Smash Push Smash!
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Old 10-31-2018, 12:58 AM   #4
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Default Re: how not to desolder

I thought one was supposed to add fresh solder before desoldering? Not using the desoldering gun itself as shown though (I always use my iron for that). The point being that, especially on ROHS boards, the hand solder lowers the joint's melting point and also promotes better thermal transfer (not to mention preheating the joint somewhat). At least for me, for all desoldering techniques (solder sucker, pumps, wick, and picks) I only get decent results by adding a little solder first.

No pre-solder, for me, usually results in a half-removed joint that's a real *** to remove (and that's after adding solder after the fact), a burn/ruined trace/pad, or both. Pre-soldering usually does the trick for me, although some situations are worse than others (Texas-sized ground planes, etc.).

I skimmed the video... Where he was doing an IC socket the results and technique didn't seem all that terrible (other than pre-soldering with the desoldering tips). For me one has to push it flush (but not hard) otherwise I don't get good thermal contact and the holes don't seal as well. Only works on non-planed joints though... as soon as I run into a hefty ground plane every desoldering gun I've ever used has mostly failed to clear the joint, and that's with a lot of preheat (and presolder)
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Old 10-31-2018, 03:23 AM   #5
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Default Re: how not to desolder

if this is the way muggles solder and/or desolder stuff these days, its no surprise why nearly all electronics are manufactured with soldering machine robots nowadays. now im really worried for the future of the electronics and tech industry if people have no clue how to properly solder.

i foresee the lost art of soldering to go the way of the jedi. a dark sith lord called darth machinus robotus killed all the jedi who knew the ways of the soldering force. now, their art is all but extinct... but i digress...
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Old 10-31-2018, 06:08 AM   #6
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Default Re: how not to desolder

worst part, if you listen to his sob story at the start about how he fucked his weller, he's been doing this shit for 30years!!!!

@RD:
he's desoldering 60/40 - the stuff he works on is 80's - 90's stuff.
i work on 70's to 90's too and use about 280 on the temp - he's pushing 360-400 there!!!
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Old 10-31-2018, 11:32 AM   #7
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Default Re: how not to desolder

Anybody who kills a Weller like he did- that's a gorilla. They are very tough stations. Now his chinese station is already screwing up. It will soon be dead.

With soldering, you have to adjust your technique. But some people just don't have that ability.

His approach - don't keep the tip there long, but crank up the temps high because muh it's not melting the solder through.
His approach - there's not enough heat, so press down harder on the tip and mash the silkscreen.
His approach - it's not desoldering, so wiggle the tip hard and trash the board and pad.
His approach - this isn't working, so repeat- add solder, wiggle trash desolder... forever...
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Old 10-31-2018, 12:22 PM   #8
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Default Re: how not to desolder

the weller he had was a good base, but the handpiece was shit - it was just a modded magnastat handle.
i had 2 of them - still have the bases - with only one good pump.

the mod the weller AND the ZD need is an extra filter to protect the pump.
i use one of these.
https://www.banggood.com/5X-Universa...-p-913243.html
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Old 10-31-2018, 06:22 PM   #9
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Default Re: how not to desolder

When I do two side boards I set the temperature to 775* F but I only leave on the pad long enough for the solder to melt then get off of the pad

I find that if I use a lower temperature it has a tendency to clog the tip or tube not suck all of the solder off the board hole that you are working on

What I noticed was that some time when that person was using the Desoldiering gun that they were put solder on the tip before heating the pad or the solder on the board

That person is just asking for the tip or the tube to really get clogged
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Old 10-31-2018, 06:32 PM   #10
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Default Re: how not to desolder

You have to WAIT A FEW SECONDS for heat to flow through to the other side of the PCB. More so if there is a copper pour (ground pour) on PCB inner layers, which acts like a heat sink.

Otherwise, you hit the vacuum and end up sucking out the solder on one side but not through the entire hole.

People can practice on a junk PCB and use their eyes to see the delay before the solder melts through to the opposite side of the board.
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Old 10-31-2018, 07:15 PM   #11
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Default Re: how not to desolder

exactly, you have to get a feel for when it's melted right through.
also, before you pump you move the tip in an orbital pattern so you suck from all around the pin and not leave it stuck to one side of the through-hole plating.

if you do it right, the part falls out - no pulling needed.

maybe we are JEDI ?

Last edited by stj; 10-31-2018 at 07:16 PM..
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Old 10-31-2018, 07:57 PM   #12
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Default Re: how not to desolder

never used one yet .. not had any problems with the old manual one .have to remember to check board markings before removing the solder as the little buggers drop right out if leads are straight through the hole .
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Old 11-11-2018, 02:06 PM   #13
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Default Re: how not to desolder

Quote:
Originally Posted by stj View Post
https://www.youtube.com/watch?v=6hGFXWGENfs

i needed to post this because this fool is blaming the tool for his lack of knowledge!

problems/mistakes:

1: using solder - you never use solder because the flux enables the solder to stick in the tool.
2: using too much heat - he's dry-jointing the solder as soon as it melts.
3: not pushing the trigger long enough - you need to clear the solder from the tool as well as the pcb.
4: desoldering downwards - your fighting gravity and molten solder can drop back down onto the pcb.
5: removing the splash-plate from the collector - it will make it block the pump much faster
6: blaming the tool for the other 5 mistakes!!

oh yea, 7 - he complains that it takes forever to cool down.
that's thermal-mass, and it's a good thing.
Desoldering downwards shouldn't be an issue, even if it is fighting against gravitiy, a good tool shouldn't have much problem with that. Even my LF-8800 crap shit thing didn't.

BUT you forgot one thing:
You do NOT press the gun against the PCB so that it bends....
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Old 11-11-2018, 02:53 PM   #14
stj
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Default Re: how not to desolder

he did that? i never even noticed that detail!!
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Old 11-11-2018, 06:49 PM   #15
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Default Re: how not to desolder

it is whatever works for you .
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Old 11-20-2018, 07:14 AM   #16
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Default Re: how not to desolder

what about re soldering wouldnt all the heat damage the new led?
https://youtu.be/muxJKP_klVI?t=1141
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Old 11-20-2018, 09:59 AM   #17
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Default Re: how not to desolder

lol - i like his audio editing.

he should be o.k. if he avouds the lense - high power leds are expected to get hot.
having said that, 80% of the problem he had was simply because he scraped the track to get more area,
but didnt tin it afterwards - if he had tinned it the led would have gone straight on.
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Old 11-20-2018, 12:18 PM   #18
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Default Re: how not to desolder

Quote:
Originally Posted by stj View Post
lol - i like his audio editing.

he should be o.k. if he avouds the lense - high power leds are expected to get hot.
having said that, 80% of the problem he had was simply because he scraped the track to get more area,
but didnt tin it afterwards - if he had tinned it the led would have gone straight on.
Too be fair some of his videos are very informative and are good,true like you say these are high power leds so the heat shouldnt really be a issue, the other issue maybe as the led didnt sit on the old pads correctly when putting the lens back on you would have to get it central over the lens i guess as may create spots on the lcd screen.
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Old 11-20-2018, 01:21 PM   #19
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Default Re: how not to desolder

depending on the type of led, he may not have used the lens
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