Questions about some lab tools I want to buy.

[saturation]

Not to belabor the poor HH but this thread covers more of issues as well as in the archives:

https://www.eevblog.com/forum/general-chat/helping-hands-good-or-bad/?topicseen

"You can NOT damage a part with a (properly adjusted) soldering iron."

Temp cycling to 175^oC, that's only during testing to meet is max operational temp spec of ~100-125^oC, soldering temps are different spec.   That won't melt lead, much less lead free solder.

On soldering, Most components have specific limits, ~ MILSTD 202, or ~250^oC for 10 seconds, lead temps.  Its not infinite.  However, the more you exceed it either in temp or time, the greater chances that components no longer meet the published specs.  To put probability in your favor, temp regulated irons, limited exposure in reflow profiles, supplanted sheer technique to reduce the risk of parts injury.

The worse is when the part isn't dead, but has changed spec.  They it creates unpredictable problems that are best solved by prevention.

http://electronics.stackexchange.com/questions/3252/what-kind-of-damage-could-a-soldering-iron-do-to-a-component

However, in hand soldering, most folks don't believe in keeping their irons even moderately in calibration:

https://www.eevblog.com/forum/general-chat/do-you-calibrate-your-soldering-station-if-not-or-if-so-why/msg58268/#msg58268

In all, cool is the rule, and the less exposure to heat you put your parts through, the more reliable the overall device will be and longer it will live, whether it be operational temp to exposure during soldering.
 

[free_electron]

I stand by what i said earlier : if you look at the reflow provile JEDEC 20C: the parts are fully immersed in 270 degrees C ( for leadfree ) for up to 60 seconds....

thus : You are not going to do any damage with a PROPERLY regulated soldering iron. If you know how to solder : apply blob of solder to tip , push tip in contact with to be soldered object , apply a bit more solder wire , retract tip. A trained soldering person does this in less than two seconds with a properly temperature adjusted iron with a decent thermall mass and wattage.

Here is another common big mistake : confusing wattage and temperature.

A lot of people are afraid to use 80 watt soldering irons on tiny parts. Instead they sit there and bake the part with a crummy 20 watt iron.
The higher the wattage and thermal mass ( a big fat stem with a short tiny tip works better than a long skinny tip ) the faster the iron can transfer its heat to the, to be joined, elements.  Get the iron in and out in a few seconds. IF you have no means to tranfer heat ( little thermal mass and slow re-heating due to low wattage ) you take 10 seconds to bring everything up to temperature ... not good !

And another one : the proper technique is to make a wet-joint. : apply a bit of fresh solder to the tip , and then 'wipe' this dab of solder onto the joint area , adding a bit more after it starts flowing. 'Dry soldering' is the WORST you can do... the problem is again heat transfer. the contact area is very small between tip and object. adding a drop of solder to the tip before increases the contact surface and gives better and faster heat transfer. There is a second aspect : in dry soldering you heat the two surfaces that need soldering and then you apply cold solder ... this gives a temperature dip ( even though very short ) and causes thermal stress in the solder joint. If you have liquid solder on the tip there is only a single heating cycle without a 'dip' in the profile.

[SH@RK]

Sorry for being late , I will try to reply all of you .

Thanks for every one .

it would help if we know what you are trying to build ?

fluxpen : unless you go about messing with SMD parts : not needed. solder has flux in it
Arduino : eh .. how many is up to you ...
Helping hands ... useless. i never use those things. they fall over and are generally annoying. use thumb and index finger to hold solder , middle finger and ring finger hold wire to be tinned. other hand holds soldering iron ... done.

heat sink for soldering ? you plan on putting that in the baking sun down there in saudi arabia , let it heat up and then use it to solder ? i think you mean soldering iron right ?

flash circuit ? what do you want to do with that ? (i'm a bit spooked on this one since you say "this is all on my 'mined' for now "... )

I do not know what I am going to build yet . I am studying Electrical Engineering so I will try to experiment everything I learn in university , and will do other things like fixing electronics  modifying them for my needs .

I think I will do SMD so I will get the flux

I think I will not get the helping hands unless I need them in future . I will try your method .

For the heat sink (I liked your idea , may be I try it) , I meant the clips that get the heat so it will not affect the parts .

You may understand this better than my explanation  http://www.kpsec.freeuk.com/solder.htm

For the flash , I want to use it as Joule Thief .

BoredAtWork

I will try to build one and see if it works or not .

Mechatrommer

I know it was a joke (it is good to be fun even in work)
I will get the solder braid . Thanks for adding it .

LEECH666

Good advice , will try to build it myself and I will get tow Arduino .

I think I will leave one fixed for lights in my house and one for work with it in my Lab .

Maybe we have to choose that for him also.

Only I forgot to tell in first post .

I think by "heatsink" the OP means those little gadgets that look a bit like flat alligator clips,that are supposed to be used to protect small leaded components,wire insulation which shrinks back when soldering,& things like that.

Yes , this is what I meant .

I will add what I have in my lab so you all can tell me what I really need to get .

Now trying to get Fluke 87 v or better on eBay (I only have Sinometer MS8268) .

I read that the fluke life warranty does not include what is sold on eBay .

Do u think I will need the warranty so I will pay the extra money for an official seller ?

Can I live without the warranty ?

How much should I pay as max price for good used one or new one in eBay ?

THanks for all of you

[SH@RK]

I want to buy a new Fluke 87v from amazon because there price is great for me (will save me 100$) .

the problem is I do not know if they sell the ones with the GSM problem or not .



Anyone can help ?

I talked with amazon livechat but they have no idea about the problem .

I sent an email to service.status@fluke.com but no respond since yesterday

thanks

[robrenz]

Just don't put your cell phone right next to the meter. Seriously, when is that an real issue?

[saturation]

Hi free, I agree with you in spirit.  But those unaware should know JEDEC or IPC standards for reflow are not one value either, there are various levels depending on the components you use, these determine the liquidus temperature and for how long to expose them.  This link to a draft is free, the complete version can be distributed only to JEDEC/IPC members.

http://www.ferroxcube.com/envir/info/J-STD-020C%20Proposed%20Std%20Jan04.pdf

The "-up to 60 seconds" depends on the factory engineer on what they want the machine set at, and I leave the true choice for temp maximums and times to those folks [not me, I don't work in production].  Most JEDEC levels are much lower than 270C.  Also, hand soldering temp limits are different from reflow limits, and part of damage is also from thermal shock: getting too hot too soon and cooling down too quickly, versus gradual heating curves and pre-heating in reflow processes; these puts different stresses on parts than sticking a 300C iron onto a part at uncontrolled room temperatures.
 
I agree parts are more robust that the spec sheets say they should, but temp limits are set by spec change or parts loss probability, its not absolute, so one can always play to win by keeping cool as the rule.

I stand by what i said earlier : if you look at the reflow provile JEDEC 20C: the parts are fully immersed in 270 degrees C ( for leadfree ) for up to 60 seconds....
..

[T4P]

Nevermind, just keep all phones and Laptops with wifi away from a 87v if it seems so

[SH@RK]

Just don't put your cell phone right next to the meter. Seriously, when is that an real issue?

I will not , but hopefully my father will not (we share tools)
I do not know if it is an issue or not , but since Dave made 2 videos about it I think it should be .

Nevermind, just keep all phones and Laptops with wifi away from a 87v if it seems so

I will , but the problem is my room is small and everything in it (my lab and computers and bed and even the main internet router in it)

So I do not want to do it even accidentally .


I will order it from amazon .

I want another used one so I can do voltage and current at the same time .

I am thinking of the same 87v used from eBay .

So how much should be the maximum price for used one (assuming clean unit and with the test leads and yellow holster only ) ? 

observing the sold units last week all above 100$ and some even have cracks .

Do u think I should not buy second 87v and search for an other model ?

Thanks

[Monkeh]

If it's brand new from Amazon, of course it won't have the issue. They fixed it some time ago.

[SH@RK]

If it's brand new from Amazon, of course it won't have the issue. They fixed it some time ago.

the newest comment said that the unit he received has the issue (April 30, 2012)

new problem

How much should I consider the fluke warranty ?

Because the units soled in amazon does not have the warranty .

I just received the response for my email from fluke said

"Since Amazon is not considered a Fluke distributor, anything you buy from them has no warranty.
If you buy equipment from the States, most international reps/distributors will not honor the warranty.

Regards,
                Fluke Customer Support"
In amazon livechat they told me that amazon is Fluke distributor , , so which one is nor wrong ?

In the local Fluke distributor in my place 87v cost 1650 SR = 440 $

So does the warranty and local support worth the 124 $ ?

Or should I forget about the warranty and get one from amazon or eBay and buy other tools from the saved 124 $

Thanks

[M. András]

they wont even ship you overseas from the states, or they will lose the distributor rights to fluke (not talking about amazon, they are just a market place) this from tequipment and the local distributor in my country confirmed this too when i bought my 289 last month