tinning a pcb

[Johan Wagener]

I finally received my 4 pcb's which the university manufactured
directly from the pcb layout dr. Leach has on his website.

I noticed that they already tinned the pcb with a thin layer of solder
or lead (silver stuff). I would like to tin it even more because I
want the tracks to conduct maximum current when running it on lower
loads.

How would I go about to neatly tin the tracks? A solder iron and
solder just doesn't do a neat job.

I has thinking using a heat gun and solder?

Any ideas?

Also, Is the tracks on the leach amp pcb layout of dr. leach big
enough to run 4-ohm loads? I noticed that they are quite narrow. I
realise the the higher voltage makes for less current but I am still a
bit concerned.

 

[Tim Wescott]

Johan Wagener wrote:

I finally received my 4 pcb's which the university manufactured
directly from the pcb layout dr. Leach has on his website.

I noticed that they already tinned the pcb with a thin layer of solder
or lead (silver stuff). I would like to tin it even more because I
want the tracks to conduct maximum current when running it on lower
loads.

How would I go about to neatly tin the tracks? A solder iron and
solder just doesn't do a neat job.

I has thinking using a heat gun and solder?

Any ideas?

Also, Is the tracks on the leach amp pcb layout of dr. leach big
enough to run 4-ohm loads? I noticed that they are quite narrow. I
realise the the higher voltage makes for less current but I am still a
bit concerned.

The coating is most likely real live tin -- it's fairly easy to plate on
to copper.

Solder doesn't conduct nearly as well as copper, so if you want to
increase the conductivity you should choose the tracks that you feel are
marginal and solder some bare copper wire along the track. Not only
will the wire determine the shape of the solder for a neater job, but
you'll get oodles less resistance than blobbing on solder.

--

Tim Wescott
Wescott Design Services
http://www.wescottdesign.com

 

[Active8]

On Wed, 28 Apr 2004 10:43:07 -0700, Tim Wescott wrote:

Johan Wagener wrote:

I finally received my 4 pcb's which the university manufactured
directly from the pcb layout dr. Leach has on his website.

I noticed that they already tinned the pcb with a thin layer of solder
or lead (silver stuff). I would like to tin it even more because I
want the tracks to conduct maximum current when running it on lower
loads.

How would I go about to neatly tin the tracks? A solder iron and
solder just doesn't do a neat job.

I has thinking using a heat gun and solder?

Any ideas?

Also, Is the tracks on the leach amp pcb layout of dr. leach big
enough to run 4-ohm loads? I noticed that they are quite narrow. I
realise the the higher voltage makes for less current but I am still a
bit concerned.

The coating is most likely real live tin -- it's fairly easy to plate on
to copper.

Solder doesn't conduct nearly as well as copper, so if you want to
increase the conductivity you should choose the tracks that you feel are
marginal and solder some bare copper wire along the track. Not only
will the wire determine the shape of the solder for a neater job, but
you'll get oodles less resistance than blobbing on solder.

I ran into a site today that gave up on hot air solder leveling long
ago to get ready for the lead free PCB world. The use immersion tin
and optionally silver or nickel berrilium gold. They charge $0.50
USD per sq in for the gold but it's $500 min because they have to
use a whole ounce of gold and the solution only lasts 3 days.
--
Best Regards,
Mike

 

[budgie]

On Wed, 28 Apr 2004 20:24:31 -0400, Active8 <reply2group@ndbbm.net> wrote:

I ran into a site today that gave up on hot air solder leveling long
ago to get ready for the lead free PCB world. The use immersion tin
and optionally silver or nickel berrilium gold. They charge $0.50
USD per sq in for the gold but it's $500 min because they have to
use a whole ounce of gold and the solution only lasts 3 days.

sounds like CustomPCB

 

[Active8]

On Thu, 29 Apr 2004 09:19:14 +0800, budgie wrote:

On Wed, 28 Apr 2004 20:24:31 -0400, Active8 <reply2group@ndbbm.net> wrote:

I ran into a site today that gave up on hot air solder leveling long
ago to get ready for the lead free PCB world. The use immersion tin
and optionally silver or nickel berrilium gold. They charge $0.50
USD per sq in for the gold but it's $500 min because they have to
use a whole ounce of gold and the solution only lasts 3 days.

sounds like CustomPCB

Hey, it was! Actually there was no mention of immersion tin now that
I look again. Probably because silver will be more compatible with
lead free solder.
--
Best Regards,
Mike

 

[Bob Masta]

On 28 Apr 2004 10:32:26 -0700, johanwagener@webmail.co.za (Johan
Wagener) wrote:

I finally received my 4 pcb's which the university manufactured
directly from the pcb layout dr. Leach has on his website.

I noticed that they already tinned the pcb with a thin layer of solder
or lead (silver stuff). I would like to tin it even more because I
want the tracks to conduct maximum current when running it on lower
loads.

How would I go about to neatly tin the tracks? A solder iron and
solder just doesn't do a neat job.

I has thinking using a heat gun and solder?

Any ideas?

Also, Is the tracks on the leach amp pcb layout of dr. leach big
enough to run 4-ohm loads? I noticed that they are quite narrow. I
realise the the higher voltage makes for less current but I am still a
bit concerned.

I tin all the boards I make by hand. I do this to prevent
corrosion... and because they are so beautiful afterwards!
It's not hard when you get the hang of it. The most important thing
is to get some liquid resin flux and paint a thin layer over the
copper. Then, use the side of the iron tip and apply normal
resin-core solder from a roll. You will quickly learn how to "paint"
the solder over the foil, and you can get a nice shiny surface with
just a little practice.

I tried the "electroless tin" solutions many years ago and gave
up in disgust. The surface was dull gray and porous, and just
about impossible to solder to.

However, I suspect that your concerns in this case are
unfounded. The resistance of the traces is going to be
totally insignificant compared to circuit resistances.
If the boards are already tinned they are protected
from corrosion. Just go enjoy the sound!


Bob Masta
dqatechATdaqartaDOTcom

D A Q A R T A
Data AcQuisition And Real-Time Analysis
www.daqarta.com

 

[Ian Stirling]

In sci.electronics.design Tim Wescott <tim@wescottnospamdesign.com> wrote:

Johan Wagener wrote:

I finally received my 4 pcb's which the university manufactured
directly from the pcb layout dr. Leach has on his website.

I noticed that they already tinned the pcb with a thin layer of solder
or lead (silver stuff). I would like to tin it even more because I
want the tracks to conduct maximum current when running it on lower
loads.
snip
Solder doesn't conduct nearly as well as copper, so if you want to
increase the conductivity you should choose the tracks that you feel are
marginal and solder some bare copper wire along the track. Not only
will the wire determine the shape of the solder for a neater job, but
you'll get oodles less resistance than blobbing on solder.

..2mm thickness of solder equals the resistance of 1oz copper.

 

[Active8]

On Thu, 29 Apr 2004 13:21:17 GMT, Bob Masta wrote:

On 28 Apr 2004 10:32:26 -0700, johanwagener@webmail.co.za (Johan
Wagener) wrote:

I finally received my 4 pcb's which the university manufactured
directly from the pcb layout dr. Leach has on his website.

I noticed that they already tinned the pcb with a thin layer of solder
or lead (silver stuff). I would like to tin it even more because I
want the tracks to conduct maximum current when running it on lower
loads.

How would I go about to neatly tin the tracks? A solder iron and
solder just doesn't do a neat job.

I has thinking using a heat gun and solder?

Any ideas?

Also, Is the tracks on the leach amp pcb layout of dr. leach big
enough to run 4-ohm loads? I noticed that they are quite narrow. I
realise the the higher voltage makes for less current but I am still a
bit concerned.

I tin all the boards I make by hand. I do this to prevent
corrosion... and because they are so beautiful afterwards!
It's not hard when you get the hang of it. The most important thing
is to get some liquid resin flux and paint a thin layer over the
copper. Then, use the side of the iron tip and apply normal
resin-core solder from a roll. You will quickly learn how to "paint"
the solder over the foil, and you can get a nice shiny surface with
just a little practice.

I've wicked off the excess. Works good.

I tried the "electroless tin" solutions many years ago and gave
up in disgust. The surface was dull gray and porous, and just
about impossible to solder to.

Mine are always nice and relatively shiny. You have to start with
immaculately clean copper and you can't contaminate the solution.
Then you neutralize with ammonia and rinse in HOH.

However, I suspect that your concerns in this case are
unfounded. The resistance of the traces is going to be
totally insignificant compared to circuit resistances.
If the boards are already tinned they are protected
from corrosion. Just go enjoy the sound!

Bob Masta
dqatechATdaqartaDOTcom

D A Q A R T A
Data AcQuisition And Real-Time Analysis
www.daqarta.com

--
Best Regards,
Mike

 

[JeffM]

Then you neutralize with ammonia and rinse in HOH.
Active8

Watch out with that Hydrogen Hydroxide!
Isn't that what they use to make Lutefisk?

 

[budgie]

On Thu, 29 Apr 2004 08:19:24 -0400, Active8 <reply2group@ndbbm.net> wrote:

On Thu, 29 Apr 2004 09:19:14 +0800, budgie wrote:

On Wed, 28 Apr 2004 20:24:31 -0400, Active8 <reply2group@ndbbm.net> wrote:

I ran into a site today that gave up on hot air solder leveling long
ago to get ready for the lead free PCB world. The use immersion tin
and optionally silver or nickel berrilium gold. They charge $0.50
USD per sq in for the gold but it's $500 min because they have to
use a whole ounce of gold and the solution only lasts 3 days.

sounds like CustomPCB

Hey, it was! Actually there was no mention of immersion tin now that
I look again. Probably because silver will be more compatible with
lead free solder.

Interestingly, I got a batch of 32 boards from them less than 2 weeks back. I'm
still using conventional tin/lead solder, and I observed what I would call
"poisoning" of the iron - while working on these boards, the solder seemed VERY
reluctant to wipe off the iron. Can't think of what else to call it or how
wlese to describe it. I'll certainly monitor this on future work on the
immersion silver plated boards.

 

[budgie]

On Thu, 29 Apr 2004 13:21:17 GMT, NoSpam@daqarta.com (Bob Masta) wrote:

(snip)

I tried the "electroless tin" solutions many years ago and gave
up in disgust. The surface was dull gray and porous, and just
about impossible to solder to.

One supplier once sent me a batch with that finish, with the same experience.
It took inordinate amounts of time/heat to get decent solder adhesion, and that
resulted in some board damage. He never got any more work from me.

 

[Roger Hamlett]

"budgie" <me@privacy.net> wrote in message
news:jh6490h5n08frjsf8lkmb2iiqtnn4boovm@4ax.com...

On Thu, 29 Apr 2004 13:21:17 GMT, NoSpam@daqarta.com (Bob Masta) wrote:

(snip)

I tried the "electroless tin" solutions many years ago and gave
up in disgust. The surface was dull gray and porous, and just
about impossible to solder to.

One supplier once sent me a batch with that finish, with the same
experience.
It took inordinate amounts of time/heat to get decent solder adhesion, and
that
resulted in some board damage. He never got any more work from me.
You can solder quite well to this finish, if you use a solder designed to

give good wetting on an oxidised surface (such as Multicore Crystal 511).
However I can't say that the finish has much 'advantage' over leaving the
boards bare...

Best Wishes

 

[Active8]

On 29 Apr 2004 15:39:41 -0700, JeffM wrote:

Then you neutralize with ammonia and rinse in HOH.
Active8

Watch out with that Hydrogen Hydroxide!
Isn't that what they use to make Lutefisk?

Never heard of it. Ammonia is some of the worst smelling crap I've
ever had the displeasure to work with. Peaople actually scrub floors
with a dilute solution of the crap.
--
Best Regards,
Mike

 

[JeffM]

Never heard of it.
Active8

Lutefisk is Cod marinated in--wait for it--Draino.

It's something the Vikings came up with.

Ammonia is some of the worst smelling crap

I really like the guy who thought up using ammonia as a solvent for RTV

instead of vinegar. Ever got a hold of that stuff?

 

[Active8]

On 30 Apr 2004 15:15:43 -0700, JeffM wrote:

Never heard of it.
Active8

Lutefisk is Cod marinated in--wait for it--Draino.
It's something the Vikings came up with.

They had Draino?

Draino has NaOH. Are you saying it has ammonia, also?

Ammonia is some of the worst smelling crap

I really like the guy who thought up using ammonia as a solvent for RTV
instead of vinegar. Ever got a hold of that stuff?

No. Always the acetic acid stuff, IIRC.
--
Best Regards,
Mike

 

[JeffM]

Lutefisk
JeffM

Draino has NaOH. Are you saying it has ammonia, also?
Active8

Nope. Just Cod, lye, and lots of hydrogen hydroxide afterwards.

 

[Active8]

On 1 May 2004 12:34:02 -0700, JeffM wrote:

Lutefisk
JeffM

Draino has NaOH. Are you saying it has ammonia, also?
Active8

Nope. Just Cod, lye, and lots of hydrogen hydroxide afterwards.

So the Viking would have used wood ash lye like the colonials did.

That sounds foul. I remember as a kid smelling some salmon cakes
left in the fridge. I swear it smelled like ammonia. What a bitch. I
was looking forward to chewing up those bones. That's always been a
kind of novelty food for me.
--
Best Regards,
Mike

 

[Rich Grise]

"JeffM" <jeffm_@email.com> wrote in message
news:f8b945bc.0404291439.280e0d65@posting.google.com...

Then you neutralize with ammonia and rinse in HOH.
Active8

Watch out with that Hydrogen Hydroxide!
Isn't that what they use to make Lutefisk?

D'ya know the difference between Lutefisk and snot?

Little kids will eat snot.

;-}