Who a beginner need hotair/solder paste to solder these parts?

[Pedro147]

if one flips away, and you *think* you've found it, are you 100% certain it isn't one of a different value you gave up on finding earlier?

  Exactly Anything 0402 or smaller, once you lose sight or grip on it and you "think" that you found it. No way Jose, bin it and grab another one.

[Mr. Scram]

Exactly Anything 0402 or smaller, once you lose sight or grip on it and you "think" that you found it. No way Jose, bin it and grab another one.

That's what an LCR meter is for. It's not bad practice to ensure everything works and has the correct values before mounting anyway.

[Pedro147]

That's what an LCR meter is for. It's not bad practice to ensure everything works and has the correct values before mounting anyway.

 

Definitely not bad practise, but also not done in practise

Can you see a board fab house checking each individual passives value. If we cannot trust the QC of what's in the tape, what hope have we got?

That's why I leave everything in the tape (which I label on unpacking) until I am going to to use it. Sure I will "decant" them into labeled containers just prior to assembly but that's it. 

I think I break every rule here in regard to ESD but no problems yet  They are mini quadcopter flight control boards and they all work flawlessly.

[Mr. Scram]

Who says anything about board fab houses? If you build for yourself, you can prevent some headaches by testing. Remember that board fab houses test after the fact and simply discard bad boards.

[Pedro147]

Who says anything about board fab houses? If you build for yourself, you can prevent some headaches by testing. Remember that board fab houses test after the fact and simply discard bad boards.

 
All I am saying is that nobody is going to waste their time testing passives before they use them in a hobby build

However maybe I am wrong, it wouldn't be the first time.

So who here is doing this pretesting of passives in hobby builds?

[tautech]

So who here is doing this pretesting of passives in hobby builds?

So we buy strips of SMD caps on tape, little lots of 20 are the most commonly bought as you enter SMD.
Some nice Asian has written the value on the tape, will it be correct ?

When I knew the future of my hobbyist circuits was to be SMD I already had a junk pile of old boards to harvest SMD passives from but of course you don't have any idea of cap values so I dug deep and got a set of ST3 LCR tweezers.
They proved to be much more versatile than I imagined and to this day they are my goto component tester for everything. So now I don't harvest parts on the cheap, still the ST3 tweezers have pride of place as #1 tool for SMD and all PCB fault finding and rework. Despite their initial price, over the decade that I've had them their initial price has proved to be cheap.

[Pedro147]

So who here is doing this pretesting of passives in hobby builds?

So we buy strips of SMD caps on tape, little lots of 20 are the most commonly bought as you enter SMD.
Some nice Asian has written the value on the tape, will it be correct ?

Point taken and no I would be wary in that case too. I have only been buying from reputable dealers but even then mistakes can happen I suppose.

My previous comment about fab houses was just pointing out that any machine assembled boards are not going to have the passives checked prior to assembly and even testing a completed board is no guarantee that every passive is of the stated value is it? When harvesting off old boards you have no choice but to measure the values. I did buy these cheap tweezers but to be honest have never used them much. http://www.ebay.com.au/itm/Tweezers-Capacitance-Resistance-Diode-Test-Tester-Pen-Multimeter-Meter-R-C-SMD-/161595625720?epid=1037823615&hash=item259fd990f8:g:PUIAAMXQdGJRzV8S

Of course the ones you have look a hell of a lot better obviously I assume that your "real" ones are an earlier version of these http://www.smarttweezers.com/ and that price, Ouch. I would be making full use of them too.

[tautech]

I did buy these cheap tweezers but to be honest have never used them much. http://www.ebay.com.au/itm/Tweezers-Capacitance-Resistance-Diode-Test-Tester-Pen-Multimeter-Meter-R-C-SMD-/161595625720?epid=1037823615&hash=item259fd990f8:g:PUIAAMXQdGJRzV8S
Of course the ones you have look a hell of a lot better obviously

My ST3's are now updated to ST5, of which there are couple of models and I'd like to upgrade to their top model.
Even my old ones do an ESR measurement which I find extremely useful when checking electrolytics as you get the uF and ESR in the same window with a single measurement.
A couple years back I grabbed a set of Mastech tweezers, IIRC #8910, I think they are better spec'ed than those you linked but nevertheless they didn't cut it against ST3 so I gave them away.

I looked hard at SMD and made the plunge a decade ago, worried as hell if I'd manage it but with a visor magnifier it was easy, so much so that I haven't made an all TH PCB since.
Soldering these wee components onto PCB is just the start ( if you can solder), you have to see the little blighters and hold them on point while doing so. We each have our favoured methodology, mine's been KISS and develop the skills with practice. I never use solder wick as I can't bear to fork out what most robbers want for the stuff instead persevere with a manual sucker that can get everything as clean as I need it if you know how to use it. Flux is another one, until very recently never used, just rely on enough being in the flux cored solder that I use of which could be anything I have around that suits the job, The only roll I know what it is, is some I bought nearly 20 years ago, a low temp silver bearing type that is now saved for special needs.

[Nusa]

So who here is doing this pretesting of passives in hobby builds?

I often end up metering through-hole resistors just to confirm their value. But that's more out of necessity because my color vision isn't to be trusted on reading some of the color bands. Brown and red bands look very similar to me, though in really good light I can tell the difference.

[Pedro147]

So who here is doing this pretesting of passives in hobby builds?

I often end up metering through-hole resistors just to confirm their value. But that's more out of necessity because my color vision isn't to be trusted on reading some of the color bands. Brown and red bands look very similar to me, though in really good light I can tell the difference.

If I ever use through hole I do too and I sympathise and agree with you totally

[Beamin]

You can get flux core solder as small as 0.3mm diameter, and its certainly worth having some small diameter solder (<0.5mm) of the same alloy as your regular solder or solder paste when you are dealing with small passives and discretes and need to add a controlled amount of solder to a pad or joint quickly to avoid cooking the pad off the board or remelting the tack-joint at the other end.

Without suitable diameter solder, there's more fiddling around, and the risk of pad damage or is much higher: If the solder wire is too thick, its very hard to control and you often end up with excess that has to be wicked off, and paste is problematic when using an iron because you have to preposition the right amount, and its very hard to control how much ends up on the pad or joint and how much on the bit, so you are lucky if its right in one shot.  When you are using hot air or bulk reflow, that isn't a problem as all the solder in the paste in the immediate vicinity of the pad or joint will end up on the pad or joint.

Beware of kits with precisely counted small passives and discretes.  You *WILL* loose a few, its virtually unavoidable, and when hand soldering, you may loose some that stick to the soldering bit.  While it *may* be possible to quickly scrape the part off the bit, by the time you've cleaned it up, it will have been badly cooked, and you don't know how badly its terminal metallisation has been eroded by the solder so reusing such parts is unwise.  There's also a problem with unmarked caps - if one flips away, and you *think* you've found it, are you 100% certain it isn't one of a different value you gave up on finding earlier?

I had a couple caps and resistors get stuck inside the solder ball on the tip. That ruins the parts? One board in this kit is SMD soldered and the other is not. There are 20 of those 2nd from smallest parts to solder with 5 different values. I could see if you just have to solder the chips by why SMD solder one board and not the other? These kits would be great if they soldered all those really tiny passives and just left through holes and chips to do. I suspect it has something to do with saving $0.01 per unit and pawning it off on a foreign customer who will never send it back. These companies will practically suck your dick not to get negative feed back so maybe I will bitch and see if they can send me another board with it soldered. Why would you make a chip without a pin #1 dot and sell it as a kit?

I think the trick is to buy that assurance 99 cent warranty plan and have them send you a free unit. That way you get an extra device when that one 0.5mmX1.0mm cap gets eaten by your soldering iron. Think about it because they can't send an extra part for a fraction of a cent they have send you a whole new unit.

RadioShack had a "product replacement plan" on all kinds of stuff like cordless phones for 3.99. So 11 months in I would say the phones were broken (take out the batteries of course) and get a brand new model and buy another 3.99 insurance plan. I had a new set of phones/mouse/alarm clock etc. every year for about 10 years all the way until they went out of business.

I'm going to buy this 99 cent ebay insurance on everything if it works the way I think it does.

[Old Don]

You can get flux core solder as small as 0.3mm diameter, and its certainly worth having some small diameter solder (<0.5mm) of the same alloy as your regular solder or solder paste when you are dealing with small passives and discretes and need to add a controlled amount of solder to a pad or joint quickly to avoid cooking the pad off the board or remelting the tack-joint at the other end.

Without suitable diameter solder, there's more fiddling around, and the risk of pad damage or is much higher: If the solder wire is too thick, its very hard to control and you often end up with excess that has to be wicked off, and paste is problematic when using an iron because you have to preposition the right amount, and its very hard to control how much ends up on the pad or joint and how much on the bit, so you are lucky if its right in one shot.  When you are using hot air or bulk reflow, that isn't a problem as all the solder in the paste in the immediate vicinity of the pad or joint will end up on the pad or joint.

Beware of kits with precisely counted small passives and discretes.  You *WILL* loose a few, its virtually unavoidable, and when hand soldering, you may loose some that stick to the soldering bit.  While it *may* be possible to quickly scrape the part off the bit, by the time you've cleaned it up, it will have been badly cooked, and you don't know how badly its terminal metallisation has been eroded by the solder so reusing such parts is unwise.  There's also a problem with unmarked caps - if one flips away, and you *think* you've found it, are you 100% certain it isn't one of a different value you gave up on finding earlier?

I had a couple caps and resistors get stuck inside the solder ball on the tip. That ruins the parts? One board in this kit is SMD soldered and the other is not. There are 20 of those 2nd from smallest parts to solder with 5 different values. I could see if you just have to solder the chips by why SMD solder one board and not the other? These kits would be great if they soldered all those really tiny passives and just left through holes and chips to do. I suspect it has something to do with saving $0.01 per unit and pawning it off on a foreign customer who will never send it back. These companies will practically suck your dick not to get negative feed back so maybe I will bitch and see if they can send me another board with it soldered. Why would you make a chip without a pin #1 dot and sell it as a kit?

I think the trick is to buy that assurance 99 cent warranty plan and have them send you a free unit. That way you get an extra device when that one 0.5mmX1.0mm cap gets eaten by your soldering iron. Think about it because they can't send an extra part for a fraction of a cent they have send you a whole new unit.

RadioShack had a "product replacement plan" on all kinds of stuff like cordless phones for 3.99. So 11 months in I would say the phones were broken (take out the batteries of course) and get a brand new model and buy another 3.99 insurance plan. I had a new set of phones/mouse/alarm clock etc. every year for about 10 years all the way until they went out of business.

I'm going to buy this 99 cent ebay insurance on everything if it works the way I think it does.

And I'll bet you wonder why they went out of business.

[Mr. Scram]

This is why we can't have nice things.

[Ian.M]

Its also how to get into my Ignore List, so I don't have to remember who is ethically challenged.   
Your Ignore list is to be found at the bottom of the [Modify Profile] dropdown on your profile page. 

[Pedro147]

RadioShack had a "product replacement plan" on all kinds of stuff like cordless phones for 3.99. So 11 months in I would say the phones were broken (take out the batteries of course) and get a brand new model and buy another 3.99 insurance plan. I had a new set of phones/mouse/alarm clock etc. every year for about 10 years all the way until they went out of business.
I'm going to buy this 99 cent ebay insurance on everything if it works the way I think it does.

What so you are one of those guys that thinks the world owes you a living are you?

I will contact a seller if they are not living up to what they say you will receive but I draw the line at outright theft. That's just me though obviously

[Beamin]

Its also how to get into my Ignore List, so I don't have to remember who is ethically challenged.   
Your Ignore list is to be found at the bottom of the [Modify Profile] dropdown on your profile page. 

RadioShack screwed me over bigtime when I was younger and the store was robbed at gun point while I was working as a cashier. They fired me going home early that day. As far as I can tell they are the ones with bad ethics and I don't mind getting a free phone that costs them 94 cents after what they put me through. I told them multiple times they needed to take precautions at location and install a REAL security camera. They did nothing to save costs. They also didn't pay me my commission that month or that whole weeks pay. FUCK RADIO SHACK AND THE MANAGER that went home early that day making me cover his shift. My coworker got bashed over the head with the butt of a gun and they did nothing but fire them too. As for the company that sold me this kit they have sent me three broken kits and argued with me over email multiple times trying to weasel their way out of responsibility.
 So yes I consider my ethics top notch and if they try to screw me over I have no reservations about treating them the way they treat other people.

[Shock]

So yes I consider my ethics top notch and if they try to screw me over I have no reservations about treating them the way they treat other people.

Probably more believable if you didn't start originally talking about defrauding other sellers via insurance at the start, but good story about the robbery. You need to work on the delivery a little because retribution by deceit is generally not an admired trait either.