Weller WTCPT tip not hot enough

[Arfa Daily]

Now, I have a confession to make. When I started my current job 9
years ago, they told me they were switching to lead free solder. I
tried some of it at that time and it seemed fine. In the course of
this conversation I realized that I had no idea exactly what version
of lead-free we were using, so today I went into our shop and looked
at one of the spools, since I usually just pull off a few feet to take
back to my office where my bench is. What I found was spools of 60/40
tin/lead. I don't know how long that's been in use here, or if they
ever bought any more of the Rohs solder.

So at this point I have to admit that it's possible that I've been
mistaken for the past 9 years and I may have almost no Rohs soldering
experience. I apologize for my statements to the contrary. It now
seems clear why my "experience" with Rohs solder seemed to be so
positive. I'll try to find some actual Rohs to try.

I DO know that my previous workplace HAS made the switch to Rohs. I
still have friends there and it is a manufacturing environment. One of
those friends is one of their electrical engineers, so I'll make a
point of asking him how that changeover went and whether it has given
them any continuing problems.

Maybe I'll find that they went to 800 F tips, or maybe not.

-
-----------------------------------------------
Jim Adney jadney@vwtype3.org
Madison, WI 53711 USA
-----------------------------------------------

No problem Jim, and it's nice to know that there are still people out there
honest enough to admit to such a situation ! I would be interested to know
what your friend's findings have been. If you once start working with
lead-free, you won't mistake it for leaded again ! The first thing you will
notice is why you suddenly don't seem able to make a shiny 'good' looking
joint any more. The stuff is also a lot 'stiffer' as it comes off the reel.
You might be surprised just how unpleasant the the stuff is to work with,
compared to 'proper' solder - and that goes for the aggressive flux fumes as
well. I wonder if your friend's place have put in additional bench
extraction / ventilation to ensure that he doesn't breath the stuff ...

Arfa

 

[N Cook]

Eeyore <rabbitsfriendsandrelations@hotmail.com> wrote in message
news:48B8F83D.2925C2B8@hotmail.com...

N Cook wrote:

I'm not sure the critical temp is 13 deg C, has someone confused 13 deg
F
and 13 deg C?. 13 degree C is quite a normal unheated room temperature.

Also see .....
http://findarticles.com/p/articles/mi_qa5348/is_200106/ai_n21473892

Which covers the popular manufacturing formula including 0.5% Cu.

Graham

I see that in that article

Tin pest in Sn-0.5 wt.% Cu lead-free solder

Sliver solder does not supress tinpest, very much reduces its growth, but
not supressed like leaded solder.

--
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list on
http://home.graffiti.net/diverse:graffiti.net/

 

[Arfa Daily]

"Eeyore" <rabbitsfriendsandrelations@hotmail.com> wrote in message
news:48B9C9A1.47F07F9C@hotmail.com...

N Cook wrote:

Eeyore wrote
N Cook wrote:

I'm not sure the critical temp is 13 deg C, has someone confused 13
deg F

and 13 deg C?. 13 degree C is quite a normal unheated room
temperature.

Also see .....
http://findarticles.com/p/articles/mi_qa5348/is_200106/ai_n21473892

Which covers the popular manufacturing formula including 0.5% Cu.

I see that in that article

Tin pest in Sn-0.5 wt.% Cu lead-free solder

Sliver solder does not supress tinpest, very much reduces its growth, but
not supressed like leaded solder.

I wonder just what we have waiting in store for us.

I had considered applying to the Comission for exemption for all goods
regularly subjected to vibration (such as used on location video and sound
recording) and which also might be subjected to freezing temps in use or
transit which could at least exempt pro A/V gear.

I guess that just about covers almost all electronic gear then ! Lets just
go for a complete ban on lead-free solder ! Power to the electronic
engineering industry !!!!!

Hmmmm. Video gear on location in freezing temperatures .... "So viewers,
after a 2 hour descent, we see the first signs of the Titanic coming into
view in remarkably sharp detail ... " Phhhttt !!! "Oh shit ..."

It seems one (at least one) loudspeaker manufacturer successfully got an
exemption on these grounds.

Graham

 

[Arfa Daily]

"Eeyore" <rabbitsfriendsandrelations@hotmail.com> wrote in message
news:48B9C868.41B256D8@hotmail.com...

Arfa Daily wrote:

"Eeyore" wrote in message
Arfa Daily wrote:

Thinking about it, the leads went E-B-Scr-space-C. It was probably one
of
those fortuitous 'mistakes' where I was measuring the collector
voltage,
and the meter probe slipped ...

Unlike me designing power amps where a similar slip tends to result in
a
lot of magic smoke being let out.

Oh I had to work on them too ! Our company was responsible for background
music machines that were rented out ro shops etc. They used a sort of
cassette tape that was endless (!) in that it wound off the centre and
back
on to the outside. Bit like an 8 track mechanism, but only had four
tracks,
as I recall. Anyways, they had a bloody great amplifier built into them,
based on 2N3055s. Being an early design, there was no protection or bias
stabilization, and you only had to bring a 20k / volt meter near to some
points to get them to run away, releasing their magic smoke ... Happy
days.
It's back when engineers learnt the business properly d:~}

An, the days of 50uA meter movements. I do still have a small one and even
found
a leather BT case designed for it on the local market.

Graham

My good old AVO 8 Mk IV, which was originally issued to me as an apprentice
in about 1970, is still used every day. For 'resistance path' fault finding,
and semiconductor junction basic proving, it is still my instrument of
choice. There's something very comforting about seeing a needle swing over
to 'about the right place'.

I do of course have a raft of digital multimeters, both portable and bench,
and a full array of digital capacitance and ESR and so on meters for more
precise measurements where needed, but I find that a good quality analogue
meter still fits the bill for much general service work.

Arfa

 

[N Cook]

Eeyore <rabbitsfriendsandrelations@hotmail.com> wrote in message
news:48B9C9A1.47F07F9C@hotmail.com...

N Cook wrote:

Eeyore wrote
N Cook wrote:

I'm not sure the critical temp is 13 deg C, has someone confused 13
deg F

and 13 deg C?. 13 degree C is quite a normal unheated room
temperature.

Also see .....
http://findarticles.com/p/articles/mi_qa5348/is_200106/ai_n21473892

Which covers the popular manufacturing formula including 0.5% Cu.

I see that in that article

Tin pest in Sn-0.5 wt.% Cu lead-free solder

Sliver solder does not supress tinpest, very much reduces its growth,
but
not supressed like leaded solder.

I wonder just what we have waiting in store for us.

I had considered applying to the Comission for exemption for all goods
regularly subjected to vibration (such as used on location video and sound
recording) and which also might be subjected to freezing temps in use or
transit which could at least exempt pro A/V gear.

It seems one (at least one) loudspeaker manufacturer successfully got an
exemption on these grounds.

Graham

It seems that if you produce kit and some of it, as little as 5 percent, is
used in medical/military/aeronautical/space, even if only in R&D/analysis
laboratories attached to any of those industries, then you can get a
derogation for all production. On the grounds that it is unreasonable to
force a company to run 2 parallel production lines.


--
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list on
http://home.graffiti.net/diverse:graffiti.net/

 

[Old TV Repairman]

"Arfa Daily" <arfa.daily@ntlworld.com> wrote in message
news:9n8uk.126777$6s4.33322@newsfe14.ams2...

Oh I had to work on them too ! Our company was responsible for
background music machines that were rented out ro shops etc. They
used a sort of cassette tape that was endless (!) in that it wound
off the centre and back on to the outside. Bit like an 8 track
mechanism, but only had four tracks, as I recall. Anyways, they had
a bloody great amplifier built into them, based on 2N3055s. Being an
early design, there was no protection or bias stabilization, and you
only had to bring a 20k / volt meter near to some points to get them
to run away, releasing their magic smoke ... Happy days. It's back
when engineers learnt the business properly d:~}

Arfa
Hmmm...I used to be an apprentice at a company that manufactured

background music machines utilising those big cartridges. They sounded
bloody awful with violin music on - used to warble something chronic.
For test purposes us young lads recorded stuff like Jimi Hendrix on
them!

Roy

 

[Arfa Daily]

"Old TV Repairman" <cantuseitcosImatwork@somewhere.com> wrote in message
news:48bb865f$1_1@glkas0286.greenlnk.net...

"Arfa Daily" <arfa.daily@ntlworld.com> wrote in message
news:9n8uk.126777$6s4.33322@newsfe14.ams2...

Oh I had to work on them too ! Our company was responsible for background
music machines that were rented out ro shops etc. They used a sort of
cassette tape that was endless (!) in that it wound off the centre and
back on to the outside. Bit like an 8 track mechanism, but only had four
tracks, as I recall. Anyways, they had a bloody great amplifier built
into them, based on 2N3055s. Being an early design, there was no
protection or bias stabilization, and you only had to bring a 20k / volt
meter near to some points to get them to run away, releasing their magic
smoke ... Happy days. It's back when engineers learnt the business
properly d:~}

Arfa
Hmmm...I used to be an apprentice at a company that manufactured
background music machines utilising those big cartridges. They sounded
bloody awful with violin music on - used to warble something chronic. For
test purposes us young lads recorded stuff like Jimi Hendrix on them!

Roy

Sounds like we might be from the same background. Training school at
Poulton-le-Fylde near Blackpool, by any chance ?

Arfa

 

[Old TV Repairman]

"Arfa Daily" <arfa.daily@ntlworld.com> wrote in message
news:qbOuk.233888$ah4.63015@newsfe15.ams2...

"Old TV Repairman" <cantuseitcosImatwork@somewhere.com> wrote in
message news:48bb865f$1_1@glkas0286.greenlnk.net...

"Arfa Daily" <arfa.daily@ntlworld.com> wrote in message
news:9n8uk.126777$6s4.33322@newsfe14.ams2...

Oh I had to work on them too ! Our company was responsible for
background music machines that were rented out ro shops etc. They
used a sort of cassette tape that was endless (!) in that it wound
off the centre and back on to the outside. Bit like an 8 track
mechanism, but only had four tracks, as I recall. Anyways, they
had a bloody great amplifier built into them, based on 2N3055s.
Being an early design, there was no protection or bias
stabilization, and you only had to bring a 20k / volt meter near
to some points to get them to run away, releasing their magic
smoke ... Happy days. It's back when engineers learnt the
business properly d:~}

Arfa
Hmmm...I used to be an apprentice at a company that manufactured
background music machines utilising those big cartridges. They
sounded bloody awful with violin music on - used to warble
something chronic. For test purposes us young lads recorded stuff
like Jimi Hendrix on them!

Roy


Sounds like we might be from the same background. Training school at
Poulton-le-Fylde near Blackpool, by any chance ?

Arfa
Close - Ditchburns at Lytham, then Granada TV at Layton.

Roy

 

[Arfa Daily]

"Old TV Repairman" <cantuseitcosImatwork@somewhere.com> wrote in message
news:48bbb651$1_1@glkas0286.greenlnk.net...

"Arfa Daily" <arfa.daily@ntlworld.com> wrote in message
news:qbOuk.233888$ah4.63015@newsfe15.ams2...

"Old TV Repairman" <cantuseitcosImatwork@somewhere.com> wrote in message
news:48bb865f$1_1@glkas0286.greenlnk.net...

"Arfa Daily" <arfa.daily@ntlworld.com> wrote in message
news:9n8uk.126777$6s4.33322@newsfe14.ams2...

Oh I had to work on them too ! Our company was responsible for
background music machines that were rented out ro shops etc. They used
a sort of cassette tape that was endless (!) in that it wound off the
centre and back on to the outside. Bit like an 8 track mechanism, but
only had four tracks, as I recall. Anyways, they had a bloody great
amplifier built into them, based on 2N3055s. Being an early design,
there was no protection or bias stabilization, and you only had to
bring a 20k / volt meter near to some points to get them to run away,
releasing their magic smoke ... Happy days. It's back when engineers
learnt the business properly d:~}

Arfa
Hmmm...I used to be an apprentice at a company that manufactured
background music machines utilising those big cartridges. They sounded
bloody awful with violin music on - used to warble something chronic.
For test purposes us young lads recorded stuff like Jimi Hendrix on
them!

Roy


Sounds like we might be from the same background. Training school at
Poulton-le-Fylde near Blackpool, by any chance ?

Arfa
Close - Ditchburns at Lytham, then Granada TV at Layton.

Roy

Ah, right. I was one of the 'Redi Boys' that's Rediffusion. Eventually,
Granada took us over, but I was long gone by then.

Arfa

 

[Arfa Daily]

"Jim Adney" <jadney@vwtype3.org> wrote in message
news:kuurb4tf7bl79pj5fe66p629pijdjn3j25@4ax.com...

On Sat, 30 Aug 2008 10:42:02 +0100 "Arfa Daily"
arfa.daily@ntlworld.com> wrote:


I DO know that my previous workplace HAS made the switch to Rohs. I
still have friends there and it is a manufacturing environment. One of
those friends is one of their electrical engineers, so I'll make a
point of asking him how that changeover went and whether it has given
them any continuing problems.

No problem Jim, and it's nice to know that there are still people out
there
honest enough to admit to such a situation ! I would be interested to know
what your friend's findings have been.

Well, it seems that info was also bad. I called him just to find out
what their experience had been so far and found that so far they are
still exempt They have not made the switch.

Thanks for your understanding. I was very reluctant to admit my
mistake, but I felt that it was only fair to keep the discussion
honest.

-
-----------------------------------------------
Jim Adney jadney@vwtype3.org
Madison, WI 53711 USA
-----------------------------------------------

The whole situation has become very complex, with two technologies now
competing on geographical grounds. I guess if all your work, and that of
your friend's place, is US based, and not for export over here, then you
have no need to switch to RoHS approved components and solder, except maybe
on the grounds of the caveat regarding not mixing solder types. By this I
mean that I guess gear manufactured in lead-free technology is pouring into
the US from the far east, but the fact that you have no *requirement* to
preserve its lead-free status, probably means that it is getting repaired,
for the most part, with leaded solder, which may not be the best thing for
long term reliability. Not that this technology is reliable in the first
place, of course ... !! d;~}

Arfa

 

[Arfa Daily]

"Jim Adney" <jadney@vwtype3.org> wrote in message
news:eoiub49erasufk2r560iapkgf9ri78nq08@4ax.com...

On Wed, 3 Sep 2008 10:00:20 +0100 "Arfa Daily"
arfa.daily@ntlworld.com> wrote:

The whole situation has become very complex, with two technologies now
competing on geographical grounds. I guess if all your work, and that of
your friend's place, is US based, and not for export over here, then you
have no need to switch to RoHS approved components and solder, except
maybe
on the grounds of the caveat regarding not mixing solder types. By this I
mean that I guess gear manufactured in lead-free technology is pouring
into
the US from the far east, but the fact that you have no *requirement* to
preserve its lead-free status, probably means that it is getting repaired,
for the most part, with leaded solder, which may not be the best thing for
long term reliability. Not that this technology is reliable in the first
place, of course ... !! d;~}

I certainly don't know all the legal ins and outs, but my previous
employer certainly made things that were shipped to all parts of the
world. It was custom scientific gear, however, and certainly not any
kind of a commercial mass-marketed product, so it remains exempt. They
report that the exemptions get stricter every year, so they expect to
have to deal with RoHS eventually and are just hoping for now that it
remains a far distant problem.

My friend did check with one of the techs today and was told that they
have occasionally had to repair lead free boards that had come as part
of more commercial products. He reports that it was quite hard to get
the dead RoHS parts out of the board.

-
-----------------------------------------------
Jim Adney jadney@vwtype3.org
Madison, WI 53711 USA
-----------------------------------------------

Yes indeed - for all of the reasons discussed. A lot of it is to do with
technique using the stuff, and if your friend doesn't have cause to work
with it much, then he will not develop the necessary skills. I have a repair
service for a particular LCD TV power supply board which is manufactured in
lead-free. Almost invariably, when I receive them, someone has already 'had
a go'. So the first thing I have to do is to clean up all their unskilled
soldering work on electrolytics and so on that they have replaced. Often,
once this has been done, the board then works ok, so ironically for them,
they probably actually found and corrected the original fault, and then
destroyed their diagnostic work, by compounding the problem with
unsatisfactory soldering - which has almost always been carried out with
standard leaded solder, which is not only illegal, strictly speaking, but
ill-advised for reasons discussed elsewhere on the thread.

Arfa

 

[Arfa Daily]

"Eeyore" <rabbitsfriendsandrelations@hotmail.com> wrote in message
news:48BFB999.A122B73@hotmail.com...

Arfa Daily wrote:

Almost invariably, when I receive them, someone has already 'had
a go'.

May The Lord save us ! ;~)

Graham

Yes indeedy ...

Arfa

 

[Jeff Liebermann]

On Sun, 24 Aug 2008 00:18:55 +0200 (CEST), George Orwell
<nobody@mixmaster.it> wrote:

I have a Weller WTCPT soldering station with the stock TC201T handle and
PTA7 700 degrees F. tip. It's 15 years old and hasn't seen much action. I
was using it a lot 3 years ago but for the past 2 years it's been sitting
cold in the garage.

The past couple times I've used it lately the tip just didn't seem to get
as hot as I remember. You know how it is with equipment you use for a long
time, you get to know the behavior and what's normal. When I put the
heated tip against the sponge, I barely get much of a sizzle. Solder barely
melts but does melt, just barely though.

I've gone through the troubleshooting guide Weller provides for this
station, all appears normal. I have 27.3VAC from the power unit. Heater
element reads 12.9 ohms. The "magnastat" opens and closes when the tip is
inserted and removed. Unfortunately the guide doesn't cover a warm tip,
only one that's stone cold or too hot. I don't know what else to check.

I can hear the tip cycling when I turn on the base. It just seems that the
heater doesn't stay on long enough like it used to. Do the tips somehow
lose their temperature calibration? Is it time for a new soldering
station? Any opinions on the WESD51?

Nice mystery. I have about 8 Weller soldering stations with exactly
the same configuration. I've never seen that problem. It's usually
either stone cold, or seriously overheating.

I assume that the thermostat cannot be heard clicking when the iron is
running luke warm.

Maybe a bit of logic might help. The voltage and resistance that you
measured are normal. If there were any excessive resistance in the
heater part of the system, such as bad thermostat contacts, bad cord,
or bad twist lock connections in the handle, these would heat
sufficiently to create noticable damage. Only the high resistance in
the xformer area in the base could cause low output, yet still read
the correct voltage. It might also be a high resistance thermal fuse
or high resistance on/off switch.

Perhaps it would be useful to measure the resistances in the base.
Ummm... unplug the soldering iron first. When stone cold, I measure
1.5 ohms across the 117VAC power plug and 1.5 ohms across the xformer
output pins. My guess(tm) is that you'll find one or the other with a
quite different resistance.

As for a replacement, I have enough parts to build and/or repair
perhaps 10 more WTCPT soldering stations, so I've never needed to
consider an alternative. If I need one, I just build one out of junk.
Unfortunately, they'er not particularly reliable and require constant
thermostat contact cleaning. I've also had heating elements die,
thermostat movement jam from corrosion, cords fuse internally, and one
xformer short and melt. If you buy something new, buy one that
doesn't have any moving parts.


--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

 

[Jamie]

Jeff Liebermann wrote:

On Sun, 24 Aug 2008 00:18:55 +0200 (CEST), George Orwell
nobody@mixmaster.it> wrote:


I have a Weller WTCPT soldering station with the stock TC201T handle and
PTA7 700 degrees F. tip. It's 15 years old and hasn't seen much action. I
was using it a lot 3 years ago but for the past 2 years it's been sitting
cold in the garage.

The past couple times I've used it lately the tip just didn't seem to get
as hot as I remember. You know how it is with equipment you use for a long
time, you get to know the behavior and what's normal. When I put the
heated tip against the sponge, I barely get much of a sizzle. Solder barely
melts but does melt, just barely though.

I've gone through the troubleshooting guide Weller provides for this
station, all appears normal. I have 27.3VAC from the power unit. Heater
element reads 12.9 ohms. The "magnastat" opens and closes when the tip is
inserted and removed. Unfortunately the guide doesn't cover a warm tip,
only one that's stone cold or too hot. I don't know what else to check.

I can hear the tip cycling when I turn on the base. It just seems that the
heater doesn't stay on long enough like it used to. Do the tips somehow
lose their temperature calibration? Is it time for a new soldering
station? Any opinions on the WESD51?


Nice mystery. I have about 8 Weller soldering stations with exactly
the same configuration. I've never seen that problem. It's usually
either stone cold, or seriously overheating.

I assume that the thermostat cannot be heard clicking when the iron is
running luke warm.

Maybe a bit of logic might help. The voltage and resistance that you
measured are normal. If there were any excessive resistance in the
heater part of the system, such as bad thermostat contacts, bad cord,
or bad twist lock connections in the handle, these would heat
sufficiently to create noticable damage. Only the high resistance in
the xformer area in the base could cause low output, yet still read
the correct voltage. It might also be a high resistance thermal fuse
or high resistance on/off switch.

Perhaps it would be useful to measure the resistances in the base.
Ummm... unplug the soldering iron first. When stone cold, I measure
1.5 ohms across the 117VAC power plug and 1.5 ohms across the xformer
output pins. My guess(tm) is that you'll find one or the other with a
quite different resistance.

As for a replacement, I have enough parts to build and/or repair
perhaps 10 more WTCPT soldering stations, so I've never needed to
consider an alternative. If I need one, I just build one out of junk.
Unfortunately, they'er not particularly reliable and require constant
thermostat contact cleaning. I've also had heating elements die,
thermostat movement jam from corrosion, cords fuse internally, and one
xformer short and melt. If you buy something new, buy one that
doesn't have any moving parts.


Lead Free Solder in use?

http://webpages.charter.net/jamie_5"

 

[Jeff Liebermann]

On Sat, 23 Aug 2008 20:02:10 -0400, Jamie
<jamie_ka1lpa_not_valid_after_ka1lpa_@charter.net> wrote:

Lead Free Solder in use?

Ummm.... He said:
"When I put the heated tip against the sponge, I barely get
much of a sizzle. Solder barely melts but does melt, just
barely though."
If it doesn't boil water, it's not going to melt solder.

I use a PTA7 (370C) tip with the evil lead-free solder. It's not the
best, but it sorta works. A PTA8 (430C) tip works much better but
I've been burning up a tip every 3 months or so.

--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

 

[Jim Adney]

On Sun, 24 Aug 2008 00:18:55 +0200 (CEST) George Orwell
<nobody@mixmaster.it> wrote:

I have a Weller WTCPT soldering station with the stock TC201T handle and
PTA7 700 degrees F. tip. It's 15 years old and hasn't seen much action. I
was using it a lot 3 years ago but for the past 2 years it's been sitting
cold in the garage.

The past couple times I've used it lately the tip just didn't seem to get
as hot as I remember. You know how it is with equipment you use for a long
time, you get to know the behavior and what's normal. When I put the
heated tip against the sponge, I barely get much of a sizzle. Solder barely
melts but does melt, just barely though.

These are great stations, but many of them have one common flaw: One
of the crimped female pins in the base, where you plug in the iron, is
often crimped onto solid wire, and that connection will go bad within
about a year of reasonable use. Once that connection goes bad, it will
heat up and destroy the plastic connector body, so the best thing to
do is to fix it before it gives problems. When we used to buy these
new, I would fix this in new units before they were ever turned on.

If you have a large selection of pin remover tools you may have one
that will work on these, but I've often had to make do with a bit of
rolled up soda can alum sheet. It's tedious, but you really only HAVE
to remove the one solid wire. The stranded crimps will be fine.

Once you get the pin out, just solder it and put it back.

My guess is that this is what's happened to your station. The power is
being split between the heater and the connector. It's also possible
that the switch in the iron handle is going bad. That certainly
happens, but usually only after a lot of use.

The Magnestat control depends on the Curie temp of the alloy in the
little slug at the end of the tip. That will never change.

It's a little confusing that you say you can hear the Magnestat
control switching back and forth. This is normal, but it should only
happen if the tip is reaching it's 700 F Curie temp. This one
observaion makes me wonder if you're just not remembering how it used
to work.

Even if it doesn't happen to be the problem right now, it's still a
good idea to solder that pin, because it will save you headaches down
the road.

-
-----------------------------------------------
Jim Adney jadney@vwtype3.org
Madison, WI 53711 USA
-----------------------------------------------

 

[Jeff Liebermann]

On Sun, 24 Aug 2008 07:25:14 +0200 (CEST), George Orwell
<nobody@mixmaster.it> wrote:

The thing just seems to be cycling more than I would
expect.

Ok, the thermostat is cycling. I've been assuming that it was NOT
cycling.

If the temperature is as low as you measure, then the primary
temperature determining element is the magnetic in the tip. If it's
off for some reason, you will get different temperatures. I've had
the base of the tip (the shiny part with the number "7" stamped into
it) fall off. I can replace it, but the temperature regulation is
rather erratic.

I'll buy a new tip at Frys tomorrow and see if it works better.

That will probably solve the problem. You might want to buy a larger
blade tip for dealing with physically larger components.

I'm using Kester Kwik-Draw Rosin Core 60% Tin/40% Lead, .053" diameter.

I prefer 63/37 but 60/40 is good enough. It should work just fine
with the 700F tip.

What does it mean to burn up a tip? If there's no heating element in these
tips how does it burn up?

The outer plating disappears. The part that needs to be cleaned and
tinned burns up (oxidizes) if left hot and sitting around for 10+
hours per day. Eventually, I can't tin it any more. The solder just
doesn't stick. I've tried various potions for re-tinning the tips
(Kester Ultrapure Tip Tinner), and Sal Ammonica (a flux), but have had
no success in reviving the tips. Only the 800F tips seem to have the
problem as the 700F tips last much longer. I would post a photo but I
can't find a dead tip. A clue is that the tip slowly turns black
instead of the usual shiny (tinned) silver color.




--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

 

[Samuel M. Goldwasser]

George Orwell <nobody@mixmaster.it> writes:

I have a Weller WTCPT soldering station with the stock TC201T handle and
PTA7 700 degrees F. tip. It's 15 years old and hasn't seen much action. I
was using it a lot 3 years ago but for the past 2 years it's been sitting
cold in the garage.

The past couple times I've used it lately the tip just didn't seem to get
as hot as I remember. You know how it is with equipment you use for a long
time, you get to know the behavior and what's normal. When I put the
heated tip against the sponge, I barely get much of a sizzle. Solder barely
melts but does melt, just barely though.

I've gone through the troubleshooting guide Weller provides for this
station, all appears normal. I have 27.3VAC from the power unit. Heater
element reads 12.9 ohms. The "magnastat" opens and closes when the tip is
inserted and removed. Unfortunately the guide doesn't cover a warm tip,
only one that's stone cold or too hot. I don't know what else to check.

I can hear the tip cycling when I turn on the base. It just seems that the
heater doesn't stay on long enough like it used to. Do the tips somehow
lose their temperature calibration? Is it time for a new soldering
station? Any opinions on the WESD51?

You say you "can hear the tip cycling". If that's the case, it would seem
that there can't be anything wrong with the electrical parts. The tip
cycles based on reaching the curie temperature of the magnet.

Have you tried a new tip?

--
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[Samuel M. Goldwasser]

George Orwell <nobody@mixmaster.it> writes:

What does it mean to burn up a tip? If there's no heating element in these
tips how does it burn up?

I assume he means the plating gets destroyed so it doesn't tin properly
anymore. I have a pile like that.

--
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Repair | Main Table of Contents: http://www.repairfaq.org/REPAIR/
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| Mirror Sites: http://www.repairfaq.org/REPAIR/F_mirror.html

Important: Anything sent to the email address in the message header above is
ignored unless my full name AND either lasers or electronics is included in the
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[Jeff Liebermann]

On Sun, 24 Aug 2008 15:33:16 +0100, "Arfa Daily"
<arfa.daily@ntlworld.com> wrote:

I used to find that my 700 deg tips lasted for months with my Weller PTC on
10-12 hours a day, but recently, I've found them to be burning out in just a
few weeks.

I had a similar problem a few years ago. At the time, I had 3 Weller
WTCPT irons deployed. Two at my house and one at the office. The one
in my shop kept eating tips. They would slowly turn black and refuse
to tin. All my tips came from the same batch so it wasn't the tip. I
bought about 25 of these stations plus parts at an auction perhaps 20
years ago. I rotated the 3 irons between locations and found that the
problem remained with the shop location. Then, I realized that the
one thing that I was doing in the shop, but not at the other
locations, was using the iron to melt plastic parts. I tended to use
it for plastic welding and drilling. I would clean and tin the tip
immediately afterwards, but apparently the damage was already done.
I'm not sure of the exact mechanism, but something in the plastic
might be removing or trashing the plating on the tip.

About the only other possibility that I can think of is that I am doing more
lead-free work now than I was, and just maybe, the more aggressive fluxes
that are incorporated in this hateful stuff, are attacking the tip plating.

Most of the rework I do in the office is with the evil lead-free
solder. If the board used lead-free, my resoldering should use the
same. I have both types of solders and use them as required by the
type of board. I haven't seen any such tip problems with lead-free.

I spoke with an expert
on the subject, and one of his papers stated quite clearly that leaded and
lead-free should not be mixed in the same joint, as it was likely to result
in long term compromise of the joint integrity. I'm not sufficiently versed
in metalurgy or chemistry to understand why this might be, but maybe a
factor ?

I dunno. I've been told the same thing. That's why I have two rolls
of solder at each workstation. I don't really understand the failure
mechanism when mixing solder and flux types. However, now that you
mention it, I have been replacing tips at a faster rate since I've
started using some lead-free solders.

I did some Googling for soldering iron tips that were specifically
designed for lead-free soldering. I found several, but none that
bothered to mention the difference between ordinary and lead-free
tips. I'll guess that it's pure marketing and that there's no real
difference in construction, other than operating at about 50F higher
in temperature.


--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558