What I do with mine is add a couple vias to the ground pad and make sure a bit of the solder paste oozes though the vias when placing the part. Tack the part down as you normally would, then flip the board over and stick the soldering iron into one of the vias. Keep adding solder until molten solder flows out the other vias. These can also be done with Xrk971's frying pan method.
I've read all your comments with interest but what do you do when you have a large board with SMD components in the middle of it?
That's the first time I've heard of that. Do you have a link to an article about that?
Leaded solder is only an issue in high humidity, I've never had any leaching in over 50 years. It is true that leaded solder will grow whiskers (leaching) in the wrong environment,
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I think lead-free solder has been an utter disaster as far as high reliability electronics go. Lead free solder grows tin whiskers in time and these cause shorts. The tin solder literally grows whiskers from an otherwise smooth surface. This has caused $B of losses in satellite industry where a $800M satellite designed for 15yr life fails after 5 or 6yrs. Use leaded solder - it works better and lasts longer.
Danger to lead-free electronics: tin whiskers - Technology & science - Science | NBC News
https://nepp.nasa.gov/whisker/failures/
EU decision to go lead free was not done with proper study of risks and impacts. As a DIY'er you have no good reason to use lead-free solder.
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The irony is that my favorite tweezers are $2, but I got through like 20 pairs of dirt cheap tweezers to find those, so in the end they cost as much as yours.
To anyone listening, if you want good cheap tweezers that won't shoot a MELF resistor across the room, get VETUS ESD-11 or ESD-12.
lead-free
I usually use lead solder for my prototype.Lead-free is necessary for mass production probably in Japan now.But those who design a new PCB will not use lead-free because of the difficulties of removing a part. Both have the different melting temperature.This is practically very critical.You need to remove a part frequently in developing process.Lead-free is very difficult to remove than lead solder. That's why I don't use Lead-free.When I need to remove a part soldered by lead-free, I sometimes lose my way, what happens to me, why I can't remove this tiny part. Lead -free is the answer.
BTW, my favorite is ESD-17.A straight one means a launcher for me.I think everyone has their own good tweezer to hold an SMD tightly.
To hold, or to launch, that is the question.🙂
VETUS Precision Steel Tweezers - Lashes, Eyebrow, Make-Up (eyelash extensions) | eBay
I usually use lead solder for my prototype.Lead-free is necessary for mass production probably in Japan now.But those who design a new PCB will not use lead-free because of the difficulties of removing a part. Both have the different melting temperature.This is practically very critical.You need to remove a part frequently in developing process.Lead-free is very difficult to remove than lead solder. That's why I don't use Lead-free.When I need to remove a part soldered by lead-free, I sometimes lose my way, what happens to me, why I can't remove this tiny part. Lead -free is the answer.
BTW, my favorite is ESD-17.A straight one means a launcher for me.I think everyone has their own good tweezer to hold an SMD tightly.
To hold, or to launch, that is the question.🙂
VETUS Precision Steel Tweezers - Lashes, Eyebrow, Make-Up (eyelash extensions) | eBay
The problem with the Vetus tweezers is that they are positive action, you really need negative action tweezers.
This is my favorite $20 and worth its weight in gold. Built countless SMT projects with it. Will not launch parts and I actually like normal positive action and straight tips with squared points.
Techni-Tool Tweezer Stainless Steel Precision Type 00
Techni-Tool Tweezer Stainless Steel Precision Type 00
Yes, for those who have not tried them, negative tweezers are far easier to use for smt components.
The biggest problem I find with SMD is getting the blighters out of the packet. I find if once I get the first one out just leave the loose plastic end floating and then the next one is easier.
Get some small metal trays, one for each type, and dump them in.
The trays can be labelled, too.
oh god yeah, you have to acquire the skill to just take them out of the bloody packet.
My tip: don't do any SMD work in a carpeted room, better, put a white sheet on the floor.
Also, instead of tweezers you can use a stick, like a bamboo skewer, and put a small blob of blue tack at the end, that will hold a SMD part without having to worry about how much you're clamping it.
When building a first time project, a fine iron tip and flux is what you need. However, when doing a repair job, the smd tends to tilt because when the pads are not cleaned first. To avoid a lot of labor I use a diy double tip made of copper. Heat both sides of the smd at once while holding it down with an appropriate tool. This only works for components with two leads.
Lead free
Lead free is bunk for, as said before regarding removing parts and replacing them in prototyping; lead free tends to lead to lifted pads.
😡🙁 I use alot of duel transistor packages in SOT-563, or a chip in QSOP-16. Lift one of these close pin pads and it suddenly becomes difficult to fix.
I thought about using SOT-963, but then I just kept on only thinking about it not actually going to use it tho
Ha!😀
Although lead solder is not super toxic to handle, I always wash up good after using it.😉
Lead free is bunk for, as said before regarding removing parts and replacing them in prototyping; lead free tends to lead to lifted pads.
😡🙁 I use alot of duel transistor packages in SOT-563, or a chip in QSOP-16. Lift one of these close pin pads and it suddenly becomes difficult to fix.I thought about using SOT-963, but then I just kept on only thinking about it not actually going to use it tho
Ha!😀Although lead solder is not super toxic to handle, I always wash up good after using it.😉
No glue. I have specific MELF tweezers with a notch, ideal brand, that make things a lot easier.
Optics are the important bit. For work I use a Nikon SMZ-745 stereo microscope, and that makes chip parts down to 0402 reasonably straightforward, as well as 0.4mm pitch qfp parts and the like. MELF parts are incredibly easy.
First time I have heard this, and is commonly done in critical medical applications (like defibrillators) where exemptions for lead solder still apply. Since leaded solder has a high tin content I am not sure what would cause this. Are you talking about bright tin? I've not encountered this problem at work or home to date.
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