Reply
 
Thread Tools Display Modes
  #1   Report Post  
Posted to rec.audio.pro
geoff geoff is offline
external usenet poster
 
Posts: 1,481
Default Solder (again)

I hate lead-free solder and all the stress to components, tools, and PCB
that rework entails when repairing gear.

Ideally I clean off the crappy stuff as best possible, and re-solder
with regular 60/40.

But what if I didn't clean off the lead-free ? What are the implications
of a blend of lead-free and leaded solder, electrically, physically, and
chemically ?

geoff
  #2   Report Post  
Posted to rec.audio.pro
Phil Allison[_4_] Phil Allison[_4_] is offline
external usenet poster
 
Posts: 499
Default Solder (again)

Geoff wrote:

------------

I hate lead-free solder and all the stress to components, tools, and PCB
that rework entails when repairing gear.

Ideally I clean off the crappy stuff as best possible, and re-solder
with regular 60/40.

But what if I didn't clean off the lead-free ?



** When replacing components, it is easy enough to clean up the old Pb free solder and use fresh 60/40 to get a shiny and reliable joint. Same goes for cracked solder work that plagues so much gear theses days.


What are the implications
of a blend of lead-free and leaded solder, electrically, physically, and
chemically ?


** Unknowable, cos you never know Pb free alloy was used on the PCB - makers should all be forced to label PCBs with that info.

However, when the result looks dull and crystalline, it is a poor quality joint.




..... Phil
  #3   Report Post  
Posted to rec.audio.pro
geoff geoff is offline
external usenet poster
 
Posts: 1,812
Default Solder (again)

On 5/02/2018 6:35 PM, Phil Allison wrote:
Geoff wrote:

------------

I hate lead-free solder and all the stress to components, tools, and PCB
that rework entails when repairing gear.

Ideally I clean off the crappy stuff as best possible, and re-solder
with regular 60/40.

But what if I didn't clean off the lead-free ?



** When replacing components, it is easy enough to clean up the old Pb free solder and use fresh 60/40 to get a shiny and reliable joint. Same goes for cracked solder work that plagues so much gear theses days.


Short of abrading off the pads with a glass-fibre scratcy-brush-pencil
thingy (don't ya hate those invisible shards that stick in yer fingers
?), always will be a remaining tinning of whatever came first.

And wires already tinned with Pb-free and too short to snip and re-tin ?
Or if just too lazy ?



What are the implications
of a blend of lead-free and leaded solder, electrically, physically, and
chemically ?


** Unknowable, cos you never know Pb free alloy was used on the PCB - makers should all be forced to label PCBs with that info.

However, when the result looks dull and crystalline, it is a poor quality joint.


Just like Pb-free at the best of times ....

geoff
  #4   Report Post  
Posted to rec.audio.pro
Phil Allison[_4_] Phil Allison[_4_] is offline
external usenet poster
 
Posts: 499
Default Solder (again)

geoff wrote:

-------------


But what if I didn't clean off the lead-free ?



** When replacing components, it is easy enough to clean up the old
Pb free solder and use fresh 60/40 to get a shiny and reliable joint.
Same goes for cracked solder work that plagues so much gear theses days.



Short of abrading off the pads with a glass-fibre scratcy-brush-pencil
thingy (don't ya hate those invisible shards that stick in yer fingers
?), always will be a remaining tinning of whatever came first.


** IME, using flux impregnated "solder wick" does the job well enough.

BTW:

I only discovered fibre pens last year and am still discovering good uses.
Cleaning up green corrosion on PCB tracks from leaking Ni-Cd memory batteries is one - then you need to clean the residue off with a PCB cleaner spray.



...... Phil
  #5   Report Post  
Posted to rec.audio.pro
geoff geoff is offline
external usenet poster
 
Posts: 1,812
Default Solder (again)

On 5/02/2018 7:54 PM, Phil Allison wrote:
geoff wrote:

-------------


But what if I didn't clean off the lead-free ?


** When replacing components, it is easy enough to clean up the old
Pb free solder and use fresh 60/40 to get a shiny and reliable joint.
Same goes for cracked solder work that plagues so much gear theses days.



Short of abrading off the pads with a glass-fibre scratcy-brush-pencil
thingy (don't ya hate those invisible shards that stick in yer fingers
?), always will be a remaining tinning of whatever came first.


** IME, using flux impregnated "solder wick" does the job well enough.

BTW:

I only discovered fibre pens last year and am still discovering good uses.
Cleaning up green corrosion on PCB tracks from leaking Ni-Cd memory batteries is one - then you need to clean the residue off with a PCB cleaner spray.


They are amazing, even on gold-plated stuff can be controlled so as to
not cause (too much) damage.

Not as coarse as brass or steel ones. But the minute fragments that
crumble off get everywhere, and even days later can end up embedded in
digits and palms, and seem impossible to find/remove. But as so short
they seem to find their own way out after a half-day or so.

geoff


  #6   Report Post  
Posted to rec.audio.pro
Scott Dorsey Scott Dorsey is offline
external usenet poster
 
Posts: 16,853
Default Solder (again)

Geoff wrote:
I hate lead-free solder and all the stress to components, tools, and PCB
that rework entails when repairing gear.

Ideally I clean off the crappy stuff as best possible, and re-solder
with regular 60/40.

But what if I didn't clean off the lead-free ? What are the implications
of a blend of lead-free and leaded solder, electrically, physically, and
chemically ?


It depends, because all the lead-free formulations are different. But if you
don't get a nice shiny joint, suck it off and do it again.

The 60/40 or 63/37 should be nice and shiny and you can tell that it isn't
crystallized and weak inside from the look of the joint.

The lead-free joints will look dull and you can't really tell if they are good
or not without x-ray inspection.

If the contamination of lead-free stuff into the leaded solder is enough of
a problem, it will cause the joint to look dull.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."
  #7   Report Post  
Posted to rec.audio.pro
Scott Dorsey Scott Dorsey is offline
external usenet poster
 
Posts: 16,853
Default Solder (again)

geoff wrote:
On 5/02/2018 6:35 PM, Phil Allison wrote:
Geoff wrote:

** When replacing components, it is easy enough to clean up the old Pb free solder and use fresh 60/40 to get a shiny and reliable joint. Same goes for cracked solder work that plagues so much gear theses days.


Short of abrading off the pads with a glass-fibre scratcy-brush-pencil
thingy (don't ya hate those invisible shards that stick in yer fingers
?), always will be a remaining tinning of whatever came first.


Put leaded solder on over the lead-free crap. Suck it off with the Soldapulit.
Then solder the joint properly. If it looks dull, suck THAT off with the
Soldapulit and try again.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."
  #8   Report Post  
Posted to rec.audio.pro
Don Pearce[_3_] Don Pearce[_3_] is offline
external usenet poster
 
Posts: 2,417
Default Solder (again)

On 5 Feb 2018 08:50:37 -0500, (Scott Dorsey) wrote:

Geoff wrote:
I hate lead-free solder and all the stress to components, tools, and PCB
that rework entails when repairing gear.

Ideally I clean off the crappy stuff as best possible, and re-solder
with regular 60/40.

But what if I didn't clean off the lead-free ? What are the implications
of a blend of lead-free and leaded solder, electrically, physically, and
chemically ?


It depends, because all the lead-free formulations are different. But if you
don't get a nice shiny joint, suck it off and do it again.

The 60/40 or 63/37 should be nice and shiny and you can tell that it isn't
crystallized and weak inside from the look of the joint.

The lead-free joints will look dull and you can't really tell if they are good
or not without x-ray inspection.

If the contamination of lead-free stuff into the leaded solder is enough of
a problem, it will cause the joint to look dull.
--scott


It is possible to make a decent joint with lead-free solder, even when
you are gap-filling. This is a seven second video I made for our
factory, showing them how to solder the pin of an F-type connector to
a pcb

https://www.youtube.com/watch?v=F7038fKlO2s

d

---
This email has been checked for viruses by Avast antivirus software.
https://www.avast.com/antivirus

  #9   Report Post  
Posted to rec.audio.pro
Scott Dorsey Scott Dorsey is offline
external usenet poster
 
Posts: 16,853
Default Solder (again)

Don Pearce wrote:
It is possible to make a decent joint with lead-free solder, even when
you are gap-filling. This is a seven second video I made for our
factory, showing them how to solder the pin of an F-type connector to
a pcb

https://www.youtube.com/watch?v=F7038fKlO2s


It IS possible, the problem is that without special equipment you can't
really tell if it's decent or not. The guys at the factory can check it
for good fill, but I can't.

And because it's more brittle, you have to be more careful about designing
for strain relief, making sure connectors are physically secured, etc.

You can make it reliable, but it's more work.
--scott

--
"C'est un Nagra. C'est suisse, et tres, tres precis."
  #10   Report Post  
Posted to rec.audio.pro
Don Pearce[_3_] Don Pearce[_3_] is offline
external usenet poster
 
Posts: 2,417
Default Solder (again)

On 5 Feb 2018 12:46:32 -0500, (Scott Dorsey) wrote:

Don Pearce wrote:
It is possible to make a decent joint with lead-free solder, even when
you are gap-filling. This is a seven second video I made for our
factory, showing them how to solder the pin of an F-type connector to
a pcb

https://www.youtube.com/watch?v=F7038fKlO2s

It IS possible, the problem is that without special equipment you can't
really tell if it's decent or not. The guys at the factory can check it
for good fill, but I can't.

And because it's more brittle, you have to be more careful about designing
for strain relief, making sure connectors are physically secured, etc.

You can make it reliable, but it's more work.
--scott


Certainly in my application both pin and PCB were very securely
anchored. The screws right alongside the connector were really that
close for RF performance reasons, but they certainly make for a good
reliable solder joint.

d

---
This email has been checked for viruses by Avast antivirus software.
https://www.avast.com/antivirus



  #11   Report Post  
Posted to rec.audio.pro
Nil[_2_] Nil[_2_] is offline
external usenet poster
 
Posts: 251
Default Solder (again)

On 05 Feb 2018, Phil Allison wrote in
rec.audio.pro:

I only discovered fibre pens last year and am still discovering
good uses. Cleaning up green corrosion on PCB tracks from leaking
Ni-Cd memory batteries is one - then you need to clean the
residue off with a PCB cleaner spray.


Is this what you're referring to? I've never seen those before.
They look like they could be useful for a number of things.

https://www.amazon.com/Cleaner-RISEP.../dp/B071HW43DN
  #12   Report Post  
Posted to rec.audio.pro
John Williamson John Williamson is offline
external usenet poster
 
Posts: 1,753
Default Solder (again)

On 05/02/2018 19:49, Nil wrote:
On 05 Feb 2018, Phil Allison wrote in
rec.audio.pro:

I only discovered fibre pens last year and am still discovering
good uses. Cleaning up green corrosion on PCB tracks from leaking
Ni-Cd memory batteries is one - then you need to clean the
residue off with a PCB cleaner spray.


Is this what you're referring to? I've never seen those before.
They look like they could be useful for a number of things.

https://www.amazon.com/Cleaner-RISEP.../dp/B071HW43DN

I've been using one like this for about ten years now, though to be
fair, I don't do much in the way of circuit board repairs nowadays. :-

https://www.amazon.co.uk/Modelcraft-...SF7KZZJ05C0KC2

--
Tciao for Now!

John.
  #13   Report Post  
Posted to rec.audio.pro
Phil Allison[_4_] Phil Allison[_4_] is offline
external usenet poster
 
Posts: 499
Default Solder (again)

John Williamson wrote:

------------------------


I've been using one like this for about ten years now, though to be
fair, I don't do much in the way of circuit board repairs nowadays. :-


https://www.amazon.co.uk/Modelcraft-...SF7KZZJ05C0KC2


** Looks identical, but being sold as a hobby tool.

Costs about around A$6 for the pen or 10 refills from a local electronics parts wholesaler.


..... Phil
  #14   Report Post  
Posted to rec.audio.pro
geoff geoff is offline
external usenet poster
 
Posts: 1,812
Default Solder (again)

On 6/02/2018 8:49 AM, Nil wrote:
On 05 Feb 2018, Phil Allison wrote in
rec.audio.pro:

I only discovered fibre pens last year and am still discovering
good uses. Cleaning up green corrosion on PCB tracks from leaking
Ni-Cd memory batteries is one - then you need to clean the
residue off with a PCB cleaner spray.


Is this what you're referring to? I've never seen those before.
They look like they could be useful for a number of things.

https://www.amazon.com/Cleaner-RISEP.../dp/B071HW43DN



Duuno if the same principle, this this:
https://uk.rs-online.com/web/p/pcb-c...ushes/0514868/

The individual strands are extremely thin/fine.

geoff
  #15   Report Post  
Posted to rec.audio.pro
Nil[_2_] Nil[_2_] is offline
external usenet poster
 
Posts: 251
Default Solder (again)

On 05 Feb 2018, geoff wrote in
rec.audio.pro:

Duuno if the same principle, this this:
https://uk.rs-online.com/web/p/pcb-c...ushes/0514868/

The individual strands are extremely thin/fine.


It looks like the one I referred to is a specialized one for fiber
optic connectors. For general electrical contact cleaning the simple
pencil style would probably be as good or better, and for 1/4 the
price.

It looks similar to a mechanical pencil - when the tip wears down, you
push more of the cartridge out. Eventually it's used up and you replace
the cartridge. Right?


  #16   Report Post  
Posted to rec.audio.pro
geoff geoff is offline
external usenet poster
 
Posts: 1,812
Default Solder (again)

On 6/02/2018 1:21 PM, Nil wrote:
On 05 Feb 2018, geoff wrote in
rec.audio.pro:

Duuno if the same principle, this this:
https://uk.rs-online.com/web/p/pcb-c...ushes/0514868/

The individual strands are extremely thin/fine.


It looks like the one I referred to is a specialized one for fiber
optic connectors. For general electrical contact cleaning the simple
pencil style would probably be as good or better, and for 1/4 the
price.

It looks similar to a mechanical pencil - when the tip wears down, you
push more of the cartridge out. Eventually it's used up and you replace
the cartridge. Right?


Yep.

geoff
  #17   Report Post  
Posted to rec.audio.pro
Scott Dorsey Scott Dorsey is offline
external usenet poster
 
Posts: 16,853
Default Solder (again)

geoff wrote:
On 6/02/2018 1:21 PM, Nil wrote:
On 05 Feb 2018, geoff wrote in
rec.audio.pro:

Duuno if the same principle, this this:
https://uk.rs-online.com/web/p/pcb-c...ushes/0514868/

The individual strands are extremely thin/fine.


It looks like the one I referred to is a specialized one for fiber
optic connectors. For general electrical contact cleaning the simple
pencil style would probably be as good or better, and for 1/4 the
price.

It looks similar to a mechanical pencil - when the tip wears down, you
push more of the cartridge out. Eventually it's used up and you replace
the cartridge. Right?


Yep.


You will lose it or some kid will borrow it long before the cartridge is used
up.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."
Reply
Thread Tools
Display Modes

Posting Rules

Smilies are On
[IMG] code is On
HTML code is Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
63/37 Solder mcp6453[_2_] Pro Audio 46 March 15th 11 03:39 AM
Lead in Solder Ian Bell Pro Audio 76 December 24th 06 11:42 AM
Lead in Solder Ian Bell Tech 0 December 14th 06 11:27 AM
Lead in Solder Ian Bell Vacuum Tubes 0 December 14th 06 11:27 AM
Better to solder or crimp? Paul Vina Car Audio 3 October 17th 03 08:00 AM


All times are GMT +1. The time now is 04:51 PM.

Powered by: vBulletin
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Copyright ©2004-2024 AudioBanter.com.
The comments are property of their posters.
 

About Us

"It's about Audio and hi-fi"