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Topic: upgrading soldering equipment (Read 674 times) previous topic - next topic

larryd

#15
Mar 12, 2018, 09:43 pm Last Edit: Mar 12, 2018, 10:54 pm by larryd
Quote
this is something i didn't realized before but i think that this is my main problem: the placing of the ic in the perfect position.  how do you do it? just with a microscope and tweezers? sometimes i lost even 5 minutes to put it in the right place and it isn't never 100% perfect
I use a stereo microscope for fine pitch soldering and alignment.
A head magnifier @ X2 or X3 works too.

I use to solder tack an I.C. corner with solder . . .

However, for hand soldering, I now:
- liquid flux the pads, let dry so it becomes sticky.
- with tweezers, position I.C. perfectly on pads, place magnetic hold down at I.C. center. (I updated the hold down with a 3/4" magnet, the SS rod is a 2mm bicycle spoke).  Position the chip with the left hand ;) and place the hold down with the right.  ~ 5 seconds per I.C. using microscope.
- with 63/37 .02" solder with iron curved tip @400°C (quickly)



Two points:
- If you try the magnet hold down sitting on a 403 SS surface you will not go back to the way you do things now.
- If you get a chance to solder using a stereo microscope you will be astounded how good you can solder.

Urge you to go thru the 400+ posts as linked to see other hints.

Along with tweezers, I use a vacuum SMD pickup tool mentioned in the links. It is made using an air pump.

https://forum.arduino.cc/index.php?topic=445951.msg3159122#msg3159122    




No technical PMs.
The last thing you did is where you should start looking.

vinceherman

- If you get a chance to solder using a stereo microscope you will be astounded how good you can solder.
+1 to this.  I am a mediocre solderer at best.  My brother used to make hearing aids and taught me some basics.  But until I got a stereo microscope I was lost with the small stuff.
Now, I can make it work.  Not pretty, but working.


xl97

I use the solder paste that the OP mentioned, and a converted toaster oven (ControLeo2 control module and toaster oven mod kit, on the recommended toaster oven). Works great as long as I use stencils to apply the solder paste - I was never able to find solder paste that worked well from a syringe; I tried several.

I use tweezers and good lighting to place the parts; I have not found part placement to be problematic when there's a nice even layer of solder paste from a stencil - I suspect your difficulty is partly because when solder paste is dispensed manually, you don't get an even layer of it.
This is (almost) my exact process as well.. except I do NOT have a controller on my toaster oven. 

I use my vinyl cutter to make my own solder paste mask/stencils.
out source to whatever Chinese PCB fab house to get my PCB's made
solder paste from ebay (China) ... couple bucks USD.

I suppose I could try and use my laser cutter for stencils as well?  (never gave it a shot as of yet)

There is a thread where we go over all the techniques here: (mind give you some alternate solutions on what you wanna do)
http://forum.arduino.cc/index.php?topic=374806.20



larryd

From pcbway.com, when you order your PCB, a metal stencil costs only ~ $15.



No technical PMs.
The last thing you did is where you should start looking.

tinman13kup

I have a stereo microscope with a camera, but have yet to try it soldering. There seems to be a learning curve, as X,Y- no problems, but Z seems to be lacking. I was pulling a couple DIP chips from a pcb I was wanting to scrap and ended up splitting an adjoining ic, exposing the actual chip. I only have a 90x scope, but it sure is interesting even at that level of magnification. It makes soldering 0201s look like a walk in the park.


Quote
the paste kind is not important I am using plumbers soldering paste is much cheaper for long time.
I wouldn't suggest plumbers on anything unless you want the green rot. Use rosin core solder and flux, or formulas specific to electronics
Tom
It's not a hobby if you're not having fun doing it. Step back and breathe

larryd

#20
Mar 12, 2018, 11:45 pm Last Edit: Mar 12, 2018, 11:52 pm by larryd
Quote
I only have a 90x scope,
You can get a Barlow lens to reduce this down.


Most soldering scopes are ~ 3.5X to 7X, maybe up to 10 for 0402 - 0201s




No technical PMs.
The last thing you did is where you should start looking.

tinman13kup

I found the barlow lenses at amscope and just haven't investigated whether they will work with the trinocular port yet. Perhaps the barlow from my telescope would miraculously be correct.
Tom
It's not a hobby if you're not having fun doing it. Step back and breathe

aster94

#22
Mar 13, 2018, 01:12 am Last Edit: Mar 13, 2018, 01:22 am by aster94
i am having many hints from this discussion, and definitely i will need a bottle of wine to read all these discussion you linked here, thank to all of you :D

ted, what you achieved with your equipment is great, you soldered that damned stm32 perfectly!

about the solder paste i will go, as suggested by Tom,with the one made especially for electronics, i didn't read very well of the plumber one and from aliexpress it is cheap anyway, same for the flux

i will try to solve my problems about the placing of components with the vacuum pen, in the future i may try to do also the electric version with the vacuum pump

next things i will try:
-buy a new flux
-get a microscope
-get a vacuum pen
-make an hold-down

I hope that some of these will help my poor skills :D

and i am more then sure that i am not going to make my diy reflow oven, too much work and no certainty of the result

larryd

#23
Mar 13, 2018, 02:01 am Last Edit: Mar 13, 2018, 06:36 am by larryd
Got to get your tools in order ;)

My favorite tools are:

Microscope
Magnetic hold down tool
FX888D soldering iron
Curved tweezers
Hot air wand
White-Out bottle flux bottle
Dupont crimper
Magnetic tools
CNC machine
Flush cutters
Scope & logic analyzer

Not necessarily in this order.


FYI
https://m.youtube.com/watch?v=eBIjsZ1dcT0  

https://m.youtube.com/watch?v=6PB0u8irn-4    

https://m.youtube.com/watch?v=5uiroWBkdFY  

https://m.youtube.com/watch?v=lpgMY1JeOAA  

https://m.youtube.com/watch?v=_6tpQE7ptqo

https://m.youtube.com/watch?v=L_DIpklxXcI  

https://m.youtube.com/watch?v=b15MMzb_GWw  



No technical PMs.
The last thing you did is where you should start looking.

ted

I wouldn't suggest plumbers on anything unless you want the green rot. Use rosin core solder and flux, or formulas specific to electronics

green rot = paste leftovers

ted

2 years, nothing green.Hand soldered no microscope, just magnifying glass.

ted


aster94

#27
Mar 13, 2018, 07:13 pm Last Edit: Mar 13, 2018, 07:31 pm by aster94
thanks to the first video i know that i can stop to be a pussy and i don't need a fancy infrared rework station but just more experience

i am happy to discover that, in theory, i am doing all correct, i mean that i do the exactly same steps of the videos larry posted. I only differ in three things:
1) i use normal (ethanol) alcool, not IPA
2) i clean the board at the beginning and at the end (they clean it always)
3) i don't have the same results with fine pitch but on the other components i reach almost the same quality

i will buy as soon as possible a flux pen, i liked also the idea of Larry, the White-Out bottle flux, but i think that a flux pen is more accurate
about the Magnetic hold down tool have you ever though about using a extensible rod? this way you wouldn't need to move the base for every parts

maybe i would invest some money also in a better quality wire, i use the cheapest i found on aliexpress. Can someone give me any hint on solder wire / flux / solder paste? or do you consider them are all the same quality?

larryd

#28
Mar 13, 2018, 09:28 pm Last Edit: Mar 13, 2018, 10:19 pm by larryd
Quote
this way you wouldn't need to move the base for every parts
I leave the hold down at one spot, then move/slide the PCB to the location where the next SMD part is located.

Using a "solid" rod gives good strong spring action that holds the SMD part securely.



Actually, you will find the White-Out flux bottle (containing liquid flux) gives pin point accuracy.
You can easily deposited half drops or larger amounts if the bottle is squeezed.
The valve point does have to be pressed in slightly.

However, a flux pen is a must have tool also, you can have both ;)

A fine needle syringe with liquid flux is good to have too, you can have all three ;)

A small liquid flux bottle with integrated brush is nice, you can have all four ;)





No technical PMs.
The last thing you did is where you should start looking.

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