Impossible to clean solder mess during 0201 filter changement

Thread Starter

Greg S_1549818893

Joined Feb 10, 2019
2
Hello,

I want to ask if someone could help me with my big mistake cleaning/resoldering 0201 filter on my board..

My mistake was: Taking Sn 0,3Ag 0,7Cu 2%Flux solder wire at the place of my standard 60/40 or 63/37 solder wire with the same little diameter.

I have a terrible mess around my element pads etc.. and I tried to clean it with solder wick (2 types) of course with flux, but this thing won't stick and get off of my boards.

It melts very slow with 420-450°C and go back(hard) immediatly (2 times faster than standard tin)

I tried to add a little bit of standard 60/40 solder to easier suck it with solder wick, but this thing still won't get out... I can melt it and move a little on sides etc but I have absolutly not idea how to get it out from my board. (Remember it's 0201 element so I have to be carreful with other parts next to it.

I have 2 different quite good irons with smaller and bigger tips and AmScope SE400-Z microscope so I think, I have enough of basic hardware to do it, but absolutly no more ideas for that bad situation. (Flux used by me every time: MGChemicals NoCleanFlux)
PS: I'm amator still learning and I don't have hot air station.

Sorry for very bad quality of photo - taken with temporary old smarphone, in real it's mutch better and clean view.


I will appreciate a lot any kind of help!

Thank you and have a nice day!

 

dl324

Joined Mar 30, 2015
11,543
Welcome to AAC!

I can't see what you're trying to show us. Give us a zoomed out view so we can see the problem area.

For work on small parts, you need a conical tip; preferably 1/32" tip.

If you add more 63/37, it may lower the melting point enough for you to remove it.

Are the leads to the pads substantial enough for you to try solder wick? There's risk of lifting them if the solder solidifies before you get the wick removed. Heat the wick on the solder and remove it with the iron still touching when the offending solder has been wicked up.

If you don't have solder wick, you can use the copper braid from some coax permeated with flux.
 

ian field

Joined Oct 27, 2012
6,539
Hello,

I want to ask if someone could help me with my big mistake cleaning/resoldering 0201 filter on my board..

My mistake was: Taking Sn 0,3Ag 0,7Cu 2%Flux solder wire at the place of my standard 60/40 or 63/37 solder wire with the same little diameter.

I have a terrible mess around my element pads etc.. and I tried to clean it with solder wick (2 types) of course with flux, but this thing won't stick and get off of my boards.

It melts very slow with 420-450°C and go back(hard) immediatly (2 times faster than standard tin)

I tried to add a little bit of standard 60/40 solder to easier suck it with solder wick, but this thing still won't get out... I can melt it and move a little on sides etc but I have absolutly not idea how to get it out from my board. (Remember it's 0201 element so I have to be carreful with other parts next to it.

I have 2 different quite good irons with smaller and bigger tips and AmScope SE400-Z microscope so I think, I have enough of basic hardware to do it, but absolutly no more ideas for that bad situation. (Flux used by me every time: MGChemicals NoCleanFlux)
PS: I'm amator still learning and I don't have hot air station.

Sorry for very bad quality of photo - taken with temporary old smarphone, in real it's mutch better and clean view.


I will appreciate a lot any kind of help!

Thank you and have a nice day!

Modern fluxes are water soluble because the solvents were banned to save the ozone layer. You can get away with car paint cellulose thinners on old flux - but it dissolves some encapsulation plastics.
 

Thread Starter

Greg S_1549818893

Joined Feb 10, 2019
2
Thank you for your responses!
I tried a wick from MG Chemicals and even copper wire from some copper cable with flux but it still don"t want to get off of my board.
I'm sorry for quality (taken from old mobilephone near eye viewer of my Amscope microscope) I will try to make a better one later.
I think the biggest problem is rest of solder (my solder mess) with solder which melt at 430 or more celcius temp. and I can see that wick which even hot enough don't want to suck it, melt yes but not sucking solder from board.
Pads will be OK enough to use wick, if not I will try to remake them, but I think it will be OK..
My tip is 0,2 mm and 2nd 0,4-0,5 mm (but I already tried with 1,5-2 mm tip and it doesn't change a lot)
In 1-2 hours I will try again to add some 63/37 to try make a lower melting point of this mess and maybe then magically my wick will suck it better. I will let you know if it works.
Have a nice day/evening (depend of your timezone) :)
 

jpanhalt

Joined Jan 18, 2008
10,246
I use Chemtronics solder wick. Other brands may be as good. But of the ones I have tried, it is the best. It easily sucks 63/37 solder out of a PTH.

As for your problem, ChipQuik makes a very low melting solder for removing IC's. I believe it contains bismuth. If you can find any bismuth solders, they will make an alloy that melts at much lower temperatures. As a last resort, if you can find Wood's metal or any of the well-know very low melting alloys, they might work too. The problem is that if you go out on a research limb, finding the right flux may be difficult; whereas bismuth solders are fairly common.

I would first try a solder wick in which I had confidence and alloys with ordinary tin/lead solders.
 

kubeek

Joined Sep 20, 2005
5,733
There is no way the solder melts at 430C,the alloy should melt at 227C. My guess is that you got there a copper plane and you need to preheat the board to around 100C.
 

tawm

Joined Feb 8, 2019
9
There is no way the solder melts at 430C,the alloy should melt at 227C. My guess is that you got there a copper plane and you need to preheat the board to around 100C.
Maybe the iron is in deg. F? If it's somewhat out of calibration it could have trouble melting the solder then.
 
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