Soldering gun tip

[Bob Engelhardt]

I have a Weller soldering gun & the tip burned through. Not having a
spare, I took a piece of 12ga copper wire and improvised (I know, it
won't last long). I find it so fiddly to get the ends bent just right
to fit in the holes after passing through the nuts & I saw the way
around it. I passed the wire in through the SIDE & locked in down:
https://i.imgur.com/ojbDuT7.jpg

But that seemed too easy. Paraphrasing: "If it seems too easy, there
must be some problem". I can't see it, so I'm asking - what might be a
problem?

Thanks

[tschw...@aol.com]

Should be OK for as long as it lasts. I'd probably have hammered that wire to a dull point.

[Jeff Liebermann]

That works well enough, until it doesn't. A few potential problems.

1. You might notice that the typical Weller soldering gun tip is much
stiffer and harder than the soft copper wire. When you try to push on
a solder connection with the tip, the Weller tip will not bend, while
the copper wire tip will bend into a pretzel. Copper alloys can be
hardened:
"Hardening of Copper Alloys"
<https://www.totalmateria.com/page.aspx?ID=CheckArticle&site=ktn&NM=71>

2. The copper wire is likely a different resistance than the real
Weller tip. My guess(tm) is that the Weller tip has a higher
resistance than the copper wire. If you have a milliohmmeter or ESR
(equivalent series resistance) meter, measure a real Weller tip and
compare it to the copper wire tip. If the copper wire has a radically
lower resistance, you might find that transformer winding in the
soldering gun will tend to overheat (or simulate a fuse). If the tip
becomes red hot, try a longer wire, or buy a real tip. Use an IR
thermometer to measure the tip temperature. 600°- 650°F (316°- 343°C)
for lead-based solder and 650°- 700°F (343°- 371°C) for lead-free
solder.

3. The idea behind a soldering gun is to heat the tip and not the
clamp where the tip meets the screw clamps. If you want to use wire,
I suggest you bend the ends of the wire in the same manner as a real
Weller tip to obtain maximum clamping pressure and surface area:
<https://m.media-amazon.com/images/I/61F0OVzw0gL._AC_SL1500_.jpg>

4. You probably need the blob of copper on the tip to prevent the
flux from destroying the tip. Try twisting the wire near the tip and
maybe beat on the twist with a hammer.

Tech Tips Tuesday, Super Hot Soldering Gun
<https://www.youtube.com/watch?v=79uD6XwBg5E>

How to Make a Soldering Gun Tip
<https://www.youtube.com/watch?v=amBafLkEtCA>

Homeade Weller soldering gun tips DIY
<https://www.youtube.com/watch?v=U86GsflNjJQ>

More:
<https://www.youtube.com/results?search_query=weller+soldering+tip>

Full disclosure: I gave up on soldering guns years ago and no longer
have any soldering guns. Temperature controlled irons are better.

--
Jeff Liebermann je...@cruzio.com
PO Box 272 http://www.LearnByDestroying.com
Ben Lomond CA 95005-0272
Skype: JeffLiebermann AE6KS 831-336-2558

[legg]

On Sat, 24 Sep 2022 12:38:28 -0400, Bob Engelhardt
<BobEng...@comcast.net> wrote:

That's the way I did it in the late 60's, but only used the thing a
few times in a month, ususlly on solder tag terminals. It was a
what Bob Unruh taught in shops class at the local high school.

RL

[Peter W.]

https://www.youtube.com/watch?v=DS4plN51Deg

The Weller replacements are plated copper. Nothing special and not rocket science. The copper wire option will simply not last quite as long as an original as the plating resists damage from the flux, and does not anneal as easily (become soft). But if one is not pounding the tip on the workpiece, that should not be of any issue.

Further, if one wishes to be 'elegant', use a hammer to dap the wire lightly to a flattened shape at the tip fold. Even a file to make a point.

Peter Wieck
Melrose Park, PA

[Bob Engelhardt]

Thanks for the replies!

I know a copper tip doesn't last as long as the iron(?) plated Weller
ones, but I thought that it was that copper dissolves in the solder.
The tip about plating with silver solder was brilliant. I refined my
tip like that. And I got a big blob which I filed to the shape I wanted.

I have a temperature controlled iron & just use the gun when I want a
lot of heat on a crude joint. E.g., unsoldering an AC cord.

Installing the tip through the sides of the gun's arms actually doubles
the area of contact between the tip & the nut.

[Jeff Liebermann]

On Mon, 26 Sep 2022 12:43:51 -0400, Bob Engelhardt
<BobEng...@comcast.net> wrote:

>Thanks for the replies!
>
>I know a copper tip doesn't last as long as the iron(?) plated Weller
>ones,

Yep. Iron plating on copper:
<https://www.dillonsupply.com/Product/weller-8125n>
"Weller® 8125N Soldering Tip With Hex Nut, For Use With 8200 Universal
Soldering Gun, Solid Copper, Iron Plated"

Some interesting details on how iron is plated onto copper:
<https://www.finishing.com/379/18.shtml>

>but I thought that it was that copper dissolves in the solder.

Correct.

>The tip about plating with silver solder was brilliant. I refined my
>tip like that. And I got a big blob which I filed to the shape I wanted.
>
>I have a temperature controlled iron & just use the gun when I want a
>lot of heat on a crude joint. E.g., unsoldering an AC cord.
>
>Installing the tip through the sides of the gun's arms actually doubles
>the area of contact between the tip & the nut.

Measure the voltage drop? Fire up a soldering gun and measure the AC
voltage drop between the transformer secondary (threaded rods) and the
base of the tip. I would measure it for you except I don't own a
soldering gun or a thermal imaging camera. I also couldn't find any
info or photos online. I'm looking for a good excuse to buy an IR
camera, but this isn't it.