Page 1 of 2

Soldering tricks & hints

Posted: Wed Jan 15, 2014 4:50 pm
by AndreyB
Anyone can solder 1206 and 0805 by hand. You would need tweezers and thin soldering wire.

Soldering paste is a miracle, with soldering paste it is MUCH easier to solder 0805 or soic-8.

You would need tweezers, mine were $0.99 cents shipped from eBay.

Update: a Hot Air Rework Soldering Station - even a cheap one like 858D - is another miracle!

Re: Soldering tricks & hints

Posted: Thu Jan 16, 2014 12:01 am
by kb1gtt
My favorite source is from a fellow known as Cash Olsen. He's a ham who packages some top shelf paste into small syringes. He's got some videos and such on his web page as well as you can order on-line from this page, which is found here http://kd5ssj.com/solderpaste/smt-tools-and-process

Re: Soldering tricks & hints

Posted: Wed Jan 29, 2014 3:18 pm
by hasse.69
How to make stencils:

Re: Soldering tricks & hints

Posted: Wed Jan 29, 2014 3:22 pm
by AndreyB
I've purchased a really shitty toaster yesterday - $7.99

I'll write an update as soon as I try soldering with this toaster.

Re: Soldering tricks & hints

Posted: Wed Jan 29, 2014 3:24 pm
by puff
1206 is a piece of cake. I haven't tried 0805, but I expect they are all the same. I use my usual soldering iron and a wooden toothpick. Mini-usb connectors are bait more difficult. soic-8 packages are easy. but when it comes to many pads in a package (soic-20, tqfp-40) I get frustrated :D
probably, in this case buying a syringe of soldering paste and a toast oven is the easiest way to go.

Re: Soldering tricks & hints

Posted: Mon Feb 24, 2014 11:27 pm
by AndreyB
I know I have a toaster and I am supposed to try it, but I am hesitating because of the lack of control - I would not really see what's going on in there, and I need to take the toaster apart to put a zip-tier on the handle... I am too lazy for that.

So, I've tried soldering with paste any my shitty rework station. OMG! Oh My God how easy it is!

Here is the POS rework station:
Image - it's plentiful on eBay.

And here is the result. That's like 120 seconds to place these 29 components into drops of soldering paste and another 60 seconds to solder all of the them with hot air:
Image

Re: Soldering tricks & hints

Posted: Fri Mar 14, 2014 6:07 pm
by AndreyB

Re: Soldering tricks & hints

Posted: Tue May 20, 2014 1:54 pm
by AndreyB
Recommended by @
[video][/video]
[video][/video]
[video][/video]

Re: Soldering tricks & hints

Posted: Thu May 14, 2015 11:04 pm
by AndreyB
what is this pretty liquid flux this guy is using in the video above?

Re: Soldering tricks & hints

Posted: Fri May 15, 2015 1:04 am
by abecedarian
Yeah, it's liquid... Radio Shack brand catalog 64-021A from what I can tell. Don't think it's available any more though.
But even the pasty stuff would work as long as you have enough to smear around a bit. ;)

... not that I'd recommend swim suit wrestling in it....

Re: Soldering tricks & hints

Posted: Tue Jun 02, 2015 4:39 am
by chingon

Re: Soldering tricks & hints

Posted: Tue Jun 02, 2015 10:02 am
by kb1gtt
Nice and thanks for the link. It will take me some time to read through it. I see 23 pages before the top link starts to talk details, so lots of fluff in there.

Re: Soldering tricks & hints

Posted: Thu May 05, 2016 10:27 pm
by puff
okay, I'd like to share my lame experience - the perfect example of how not to do. :D
Image
Image
Image
If I recall it correctly, it was the late fall of 2014 when I got those boards soldered. I used pure alcohol (C2H5OH) to get rid of all those debris and dirt left after soldering. I though I cleaned it thoroughly. Just a few days ago I finally got back home and took that board out of a drawer just to see this ugly picture. Hope, after cleaning it will still be working. The next time I'd do it with a 50/50 mixture of alcohol and gazoline...

Re: Soldering tricks & hints

Posted: Mon May 09, 2016 3:49 am
by Horizenjob
Perhaps that was a lack of rinsing? You can dissolve the flux etc. but then you need to rinse it away or it's still there.

Gasoline seems a bad idea, mineral spirits would be far safer. I don't recollect something like that being used on any assembly lines or rework stations that I've see. Only use approved materials, I'm sure kb1gtt will have a better answer.

Re: Soldering tricks & hints

Posted: Mon May 09, 2016 11:50 am
by Rhinoman
I've had onr of these stations for many years:

http://uk.farnell.com/antex/ud82d70/rework-station-surface-mount/dp/1204732?ost=antex+surface+mount+rework+station&selectedCategoryId=&categoryNameResp=All%2BCategories&iscrfnonsku=false

A well lit magnifying lamp is essential. I can solder down to 0603 and TSSOP without issue but smaller than that and I need a higher powered binocular type magnifier - another downside of getting older.

Re: Soldering tricks & hints

Posted: Sat Aug 13, 2016 4:32 pm
by kb1gtt
I thought I'd put out some comments relative to soldering. When soldering you can get pads that lift for a variety of reasons. Lifting pads is a bit more common with low cost SMT china PCB's but is typically mostly caused by soldering temperatures that are two high. If you spend more money on the PCB, it's common the glue they use to hold the copper to the FR4 can sustain a higher temperature. However price is not a guarantee that you'll get a higher temperature adhesive. If you are trying to limit the chances of your pad(s) lifting these are some things that might help.

Limit the temperature of the iron, or limit the time you have the iron on the traces. If you didn't get it soldered fast enough, you may have to wait something like 5 minutes for it to cool down before trying again. It takes a certain amount of time for the glue to heat up. When it gets warm, it's adhesion to the FR4 gets weaker. Keep in mind it takes the FR4 a while to heat up and cool down. If you have a hot iron, it will warm the FR4 and adhesive faster. If you hold your iron on the item longer it will also make the FR4 hotter. As well it's common that when you pull the iron away such that the iron is no longer keeping it hot, the FR4 will keep the adhesive soft.

Also don't forget your soldering sequence. For example when soldering to the GND plane, it has thermal relief's but they still conduct reasonably well to the copper flood. When you do this you probably want your iron set to the max temperature such that you can heat up a small area as quick as possible. This is kind of the opposite of what I said in the above note. What I'm trying to say is that when you have a copper flood that will take lots of heat to heat it up, you can limit the time by increasing the temperature. If you try this with a lower temperature iron, you may end up heating up a large area which can cause the adhesive of near by components to loose adhesion. If you solder stuff that is connected to the copper flood, you should let the PCB cool down before you solder other components. Keep in mind the FR4 is hot and other pads will lift easy as the adhesive is probably already weak. If you let it cool, that will help increase the time you can solder smaller pads before the adhesive gets to weak.

The coating on the iron tip typically makes for a better solder finish with less bridging and such. This coating also has a tendency to help release the solder from the iron tip, which plays a roll with how likely it is for the part to lift. If the solder releases easy, it allow the adhesive to get weaker before it will start to lift. Good coatings on the iron tip help the solder break free when you pull the tip away.

Once a pad lifts, it's a real pain. When they lift the fix is more art and gut feel skill, then science. If they don't lift it's not so bad as the glue tends to re-adhere once it cools down. Once they lift you typically get dust, oxygen and such in there that prevents re-adhesion. Hot air prevents the pads from lifting, which helps allow the re-adhere when it cools.

Also don't forget those large slugs on the back of chips for thermal purposes. I generally try to allow a larger via on the back side. This allows you to put the iron in the hole and get a better conduction to the slug. The goal here is to get that heat into the slug and avoid heating the other components.

Irons were intended for thru hole, which has a much more solid form of attachment to the PCB.

I would suggest avoiding the iron and use hot air if possible.

Any how, those are a couple of comments that might be of help.

Re: Soldering tricks & hints

Posted: Fri Nov 18, 2016 3:32 pm
by AndreyB

Re: Soldering tricks & hints

Posted: Wed Dec 28, 2016 4:30 am
by AndreyB
Stenciling Tutorial by SparkFun Electronics
[video][/video]

Re: Soldering tricks & hints

Posted: Fri Feb 24, 2017 11:52 pm
by AndreyB
http://www.ebay.com/itm/302087164784 search for "Low Temperature Solder Paste 15 Grams" is a different paste option - much cheaper, more liquid and less dense. Could be a better option to solder smaller stuff like LQFP-100.

Re: Soldering tricks & hints

Posted: Fri Feb 24, 2017 11:58 pm
by stefanst
Why lead-free?
I understand trying to save the planet, but the additional 2g of lead that all the rusefi ever built would use combined are not going to do that much damage.
I much prefer soldering with lead....

Re: Soldering tricks & hints

Posted: Sat Feb 25, 2017 1:13 am
by kb1gtt
Leaded solder melts around 180C to 250C, this low temperature stuff claims to melt at 280C. So much hotter.

Re: Soldering tricks & hints

Posted: Sat Feb 25, 2017 3:31 am
by AndreyB
kb1gtt wrote:this low temperature stuff claims to melt at 280C.
eBay wrote:137C 278F Melting Point (Eutectic)
One day we will make metric great again...

Re: Soldering tricks & hints

Posted: Sat Feb 25, 2017 10:02 am
by kb1gtt
Stupid units. I wonder how they got lead free at such a low temperature. Probably used Gallium. How about we make the melting spoon trick great again :)


Re: Soldering tricks & hints

Posted: Wed Jun 20, 2018 11:20 pm
by AndreyB

Re: Soldering tricks & hints

Posted: Mon Jan 28, 2019 2:47 am
by AndreyB
I have a feeling I am getting my first glasses soon :( In the meantime maybe something like https://www.made-in-china.com/showroom/lanfeizei/product-detailABqxtRDSJTWM/China-Magnifier-Lamp-6025-1-.html

Maybe one day Santa will bring me https://www.ebay.com/itm/853AAA-Infrared-Bga-Rework-Station-60W-Tin-Soldering-Iron-Power-Functional-Air-S/202505214083 and/or a microscope like https://www.ebay.com/itm/AmScope-5X-10X-Binocular-Boom-Arm-Stereo-Microscope-LED-Gooseneck/141951406006 and I will start to like soldering LQFP-100?

"anything above 15 is useless" people say

Re: Soldering tricks & hints

Posted: Mon Jan 28, 2019 1:50 pm
by Abricos
I use it and I think it is a very good option for the price and quality .for our purposes ...
G600 Electronic Digital Lab Microscope 4.3 inch HD LCD w/Aluminum Alloy Bracket

Re: Soldering tricks & hints

Posted: Mon Jan 28, 2019 2:35 pm
by puff
Looks nice. Which is better: the pure optical one or that with an lcd screen?

Re: Soldering tricks & hints

Posted: Tue Jan 29, 2019 6:32 pm
by 960
puff wrote:
Mon Jan 28, 2019 2:35 pm
Looks nice. Which is better: the pure optical one or that with an lcd screen?
For inspection a camera is just fine.

But for soldering, working in 2d is hard.

I have tried both, and only use optical microscope.

Re: Soldering tricks & hints

Posted: Tue Mar 26, 2019 1:56 pm
by AndreyB
Frankenstein Soldering Basics


Re: Soldering tricks & hints

Posted: Thu Feb 27, 2020 12:06 am
by AndreyB
Now considering T8280 https://www.amazon.com/VEVOR-Preheating-Infrared-Preheater-280x270MM/dp/B01MCT9FAY#customerReviews love the "Works good, fan is a little noises, power cord is a fire hazard. They cord included with the machine hot too hot to touch after being run for 15 minutes." review

Probably not ready for T962 yet? Lovely paper replacement mod



and getting some https://smile.amazon.com/gp/product/B00425FUW2/