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lynnl
02-14-2013, 02:27 AM
I have a Weller model 8200 soldering gun that I bought several years ago, and have used only 3 or 4 times.

I tried to use it yesterday and it would barely melt solder directly, and seemed to only heat the tip intermittently, i.e. sometimes it seems to heat up, though slowly, and other times not at all.
It has two power levels, 140 and 100 watts. When I pull the trigger lightly I get a slight buzzing, but when I pull all the way there's no buzzing. It seems like it's not heating at all at the 140 watt level.

The tip looks to be in good shape, so I don't think that's the problem. Also when I put on one of the other auxillary tips (cutting or smoothing) they don't seem to get hot either.

The body of the gun does get pretty warm on the top, so it's not completely dead.

I opened up the case, and there's nothing to it but the trigger assembly and the coil(s), and everything looks good. Worked ok the last time I used it, as well as I recall.

The little booklet doesn't give any clues as to what the problem might be, and I've only ever used soldering irons.
Is this just a problem of my ignorance, or is this thing just a piece of junk?

darryl
02-14-2013, 03:05 AM
From what I've seen inside those, the magnet wire from the transformer goes directly to the switch. Because it's solid wire, and through use and vibration, it tends to break off at the switch terminals. If it doesn't break there, it breaks at the point where it exits the transformer windings. The winding is tapped to give you two points to put voltage to it. The full length of the winding is used for low heat, and the tap is used for high heat. If it works on low, that basically says that the winding is ok. You either have a broken connection, or the switch itself is bad.

The worst thing I've seen in those guns is when they use an aluminum loop for the secondary coil that connects to the tip. There's so little voltage at the ends of that loop that anything that interferes with current flow will put all of the heat into the connection and not the tip. That's the biggest cause of the gun itself heating up- assuming you're not pulling the trigger and just holding it on for minutes at a time.

Beazld
02-14-2013, 06:11 AM
Make sure the nuts that hold the tip on are tight. I have had similar problems in the past and traced it to that.

Lew Hartswick
02-14-2013, 07:49 AM
Odds are is the tip nuts have gotten loose. I always tighten them up a bit every week or so. A term " Thermal ratcheting" , look it up. :-)
....lew...

flathead4
02-14-2013, 08:10 AM
Just throw it away. Those things are junk - in my opinion. I had one and it worked okay for year or so and then had the same issues you describe. I went back to my 30 year old "stick" soldering iron and have had happy soldering ever since.

Tom

J Tiers
02-14-2013, 08:32 AM
I don't much like the guns vs a decent iron, or for bigger, a "soldering copper". But the folks mentioning the poor contact are right on the mark. Common problem.

Not saying it is YOUR problem, but it is very common.

There is hardly anything to go wrong..... a core, a "primary" coil of finer wire, and a coil of thick "bar" for the secondary. If the "bar" isn't cracked, and contact is decent, it nearly HAS to work so long as current flows in the primary.

firbikrhd1
02-14-2013, 08:44 AM
+1 on the nuts being not only tight but making a good connection. I usually loosen them a turn or so and re-tighten to break up any "corrosion" that might be in the threads after the using has been sitting for months, maybe years in my case.

browne92
02-14-2013, 09:44 AM
+1 on the nuts being not only tight but making a good connection. I usually loosen them a turn or so and re-tighten to break up any "corrosion" that might be in the threads after the using has been sitting for months, maybe years in my case.

I agree, and do the same thing when mine has been sitting around awhile. But the OP stated he changed tips, and it only seems to be working in one power range. Bad switch or broken connection. Sounds like it's time to break out the ohm meter.

Kevin B.
02-14-2013, 09:47 AM
I've had my Weller gun for 49 years and the only problem has been the tip nuts coming loose. Hardly what you would call junk-in my opinion.

flathead4
02-14-2013, 10:26 AM
Now my dad purchased one 40+ years ago when I was a kid and it was still working when he passed away a few years ago. The one I bought about 10 years ago was junk.

Tom

A.K. Boomer
02-14-2013, 10:48 AM
Just throw it away. Those things are junk - in my opinion. I had one and it worked okay for year or so and then had the same issues you describe. I went back to my 30 year old "stick" soldering iron and have had happy soldering ever since.

Tom

Im with you on it, I don't have the heart to throw mine away but they have got to be one of the most frustrating unreliable POS iv used over the history of my lifetime - seems like every time you go to use one - be it whether it was my Dads way back when or shops iv been at or my own you better have 5 or 10 extra minutes to jack with it and get it working or replace the tip ends they always seem to be burning out, yes most times its the tip nuts being loose but what a pain...

Stick irons are way more accurate and less cumbersome but take too long to heat up...

My solution is a two part, I now use a stick iron but also use my pull trigger propane torch - plug the iron in and zap it with the torch, you now have an instant-on ready to use very predictable and dependable iron - its the ticket for electronics and if you need "bigger balls" for larger mass of material melting then just zap the end and middle with the torch real quick.

lynnl
02-14-2013, 11:15 AM
...................
.... assuming you're not pulling the trigger and just holding it on for minutes at a time.

Whoa...! Hold on folks, maybe we're onto something here.
I had wondered about that, but the damn booklet is conspicuously silent regarding the actual, precise, correct use of it.

Yes, indeed I have held it for minutes at a time. Otherwise I'd never get any solder melted.

As for the tip connnections: I've made sure they're as tight as possible, given the crappy little screw heads that a srewdriver can barely engage.


.
There is hardly anything to go wrong..... a core, a "primary" coil of finer wire, and a coil of thick "bar" for the secondary. If the "bar" isn't cracked, and contact is decent, it nearly HAS to work so long as current flows in the primary. .

I'll open it up again; previously I didn't really know what I needed to look for.
How do these things work? ....is this induction heating?

If the switch is bad, are replacements available? Again, the booklet is silent on the mattter of repair or parts.

Thanks guys!

MaxHeadRoom
02-14-2013, 11:20 AM
I have never had any problems with both sizes of Weller Guns, Many have already posted the reason for the non-heating, what happens is after a good work out, the copper tip shrinks under the retaining screw as it cools.
I always make a point of slacken the screw and then re tighten before use, never had a problem.


How do these things work? ....is this induction heating?

There is considerably high current flowing through the tip secondary. Same principle as a resistance-spot welder.
One (shorted) turn secondary of a transformer.
BTW, many forget, on a Weller, the first pull of the switch is high heat, a full pull is low heat.
Max.

A.K. Boomer
02-14-2013, 11:48 AM
BTW, many forget, on a Weller, the first pull of the switch is high heat, a full pull is low heat.
Max.

yes very important point - usually can be verified by the change in the light bulb brightness and the sound of the windings laboring - and sometimes even with the way they melt solder - when they decide to work that is...

gvasale
02-14-2013, 12:52 PM
Also make sure the ends of the tip where held are clean. Very clean.

lynnl
02-14-2013, 01:12 PM
Also make sure the ends of the tip where held are clean. Very clean.

As I said, this one has only been used 3 or 4 times previously. So the tip is practically new looking, other than a slight build-up on the very end of the tip.
I can see little indentations where the clamping screws are biting into the prongs. So I think I'm getting good electrical contact there.

I dunno, maybe this is as good as it gets with this thing. ...but I'd not had these problems with the earlier uses of it.

I opened it up again. No obviously broken connections, but one of the wires has a somewhat blackened appearance in a tiny spot where it comes out of that primary (thin copper wire) coil.

Darryl mentioned "...holding it for several minutes..." as if that's a bad thing. How are you supposed to operate it? It would seem you'd have to hold it for a considerable period in order to heat the work hot enough to melt the solder. ...right?
I have a little 25 watt Weller iron, and even after heating up for 5 or 10 minutes I couldn't get enough heat with it to tin about 5/8" of stranded 18 ga wire.

Anybody know what those tips are made of? ...copper maybe, with a silvery plating; it seems to bend easily.

Mike Burdick
02-14-2013, 01:31 PM
Lynnl,

When my soldering gun doesn't work it's usually like others have suggested - a dirty or corroded tip. To fix this, I just sandpaper the tip's connection ends and reinstall.

The tips I have are a soft copper and can be purchased at Sears...

http://www.sears.com/search=cooper+tools+weller+7135w+replacement+solde ring+gun+tip?vName=Tools&cName=Welding+Equipment&autoRedirect=true&viewItems=25&redirectType=CAT_REC_PRED

True Value, Ace, or Home Depot may have them as well.


.

radkins
02-14-2013, 02:02 PM
I posted a similar thread a while back about this exact same problem, I eventually gave up and threw both of the junky things into the trash, as others have said they are a POS. I now do the same thing Boomer does and just use a stick iron with a propane torch as a pre-heater/booster and it works great, problem solved.

The guys who have one that has worked for years should hang on to it because it is a VERY rare collectors item!

The Artful Bodger
02-14-2013, 02:05 PM
The heater is the secondary circuit of a transformer and operates at high current, low voltage with the consequent requirement of extremely low resistance. All connections in the secondary circuit must be bright and clean.

Mike Nash
02-14-2013, 02:06 PM
My 1976-ish Weller D 550 (240/325W) is most definitely high heat at full trigger pull (I just checked again). I have noticed that later D550s are only 200/240W though. I don't have one of my several 100/140W ones handy to check. OTOH, I really don't care for the smaller ones as they aren't as hot and the guy who designed the handle shape was an idiot. I only use 12 or 14 AWG solid wire for my tips, but they do burn out fast.

As an aside, a nice 14 AWG wire loop on the D 550 made cutting out dividers in a Plano tackle box a breeze!

MaxHeadRoom
02-14-2013, 02:12 PM
This item is about as simple a piece of equipment you can get, a switch and a 1 turn secondary transformer!
I have been using both medium and large Weller for over 30yrs now, and have come to recognize the one flaw is that of the connection to the tip, apart from that there has been no problem and it has done the job asked of them!
I'll wager many have been tossed due to this simple cure!!
BTW, a clue is the lack of 60Hz buzz when you pull the trigger.
I believe not all models were dual heat, so the 8200 may have one setting?
Max.

lynnl
02-14-2013, 02:32 PM
This 8200 says it's 140/100 watts. There's no mention anywhere as to which is full pull and which is half-pull. But I definitely get the buzz at half-pull, and it stops when I pull all the way.

I've decided the issue probably is the clamping of the tip, because just for giggles I reversed the tip and put it in upside down and it heated immediately.
Guess I'll look for some new tips.
Will also try the 14ga solid copper wire. That may be just the ticket for me, as I only use it about every 4th or 5th blue moon.

MaxHeadRoom
02-14-2013, 02:45 PM
This 8200 says it's 140/100 watts. There's no mention anywhere as to which is full pull and which is half-pull. But I definitely get the buzz at half-pull, and it stops when I pull all the way.
.

It is possible you have a bad switch on full power?
Unless the reversal cured it?
Max.

Bob Fisher
02-14-2013, 04:48 PM
I have a Wen and a Weller, both about 40 plus yrs, and both suffer from this same problem. Easy to put right like has been said. Bob.

Mike Nash
02-14-2013, 05:26 PM
This 8200 says it's 140/100 watts. There's no mention anywhere as to which is full pull and which is half-pull. But I definitely get the buzz at half-pull, and it stops when I pull all the way.


I found a manual online that does state the first click is full power. But that isn't true on my older one. I like/hate the tip holding nuts on mine vs the screw collars. The nuts work better, but are way more of a pain when it is time to change tips. And the wattage is 260/200 on the "newer" bigger guns, vs 240/325 on the older. Sort of tells you which is the first click if yours is 140/100.

lynnl
02-14-2013, 06:58 PM
Sort of tells you which is the first click if yours is 140/100.

Huh! I'd not made that connection. Though I had thought it odd they would describe it as 140/100 vs. 100/140.
Nevertheless, it would've only taken a few more words in the booklet to tell us the first pull is the higher power.

I'm still in the dark as to how long it can be safely operated on one pull. Are we talking a matter of seconds, four or five minutes, or half an hour or so? (Ref post #2 above by Darryl)

J Tiers
02-14-2013, 07:26 PM
Think of the thing as being similar to a spot welder, in terms of what can go wrong.

Both are low voltage / high current, both usually are not good for continuous operation, corrosion messes both up, and loose connections mess both up. Both depend on high current to work.

In fact, you probably could spot weld small thermocouples using the proper added parts with a soldering gun....

mikem
02-14-2013, 07:57 PM
My friend Jerry (and several others) has the problem figured out. I use those in our electronic repair shop and have collected about a dozen of them of various vintages. The tips all need to be cleaned or tightened up from time to time. The nuts are 3/8, I think, and I got one of those copper flare nut wrenches to tighten them with. It doesn't round the flats of the nuts as badly.

I use copper wire in 12 or 14 gauge for a homemade tip in a pinch--it seems to heat quicker since the wire is smaller gauge than the regular tips. I even flatten the wire in the middle where I use it to solder!

My friend has a garbage route and picks them out of the trash all the time because people throw them away because they don't heat.

MaxHeadRoom
02-14-2013, 07:58 PM
I'm still in the dark as to how long it can be safely operated on one pull. Are we talking a matter of seconds, four or five minutes, or half an hour or so? (Ref post #2 above by Darryl)

There is a definite duty cycle, I had one where the trigger was getting 'iffy' I happened to leave one I had been using not realizing the switch was stuck on, I returned 15 min later and it had burnt the transformer.
Max.

jnissen
02-14-2013, 07:59 PM
DO yourself a favor and toss the POS. I use solder irons daily and have a nice digital Weller in the shop. I used to have one of the guns for large gear but it would always not be working. I repaired the thing several times and eventually just got tired of dealing with it and threw it out. In it's place I got a Master Appliance butane iron. I didn't have a portable setup and this definitely fits the bill for that but what I like is that you can dial up the heat and it's really a great high power iron. Quality build and works like it should. It's not the lowest cost but good tools rarely are.

Arcane
02-14-2013, 08:13 PM
I must be living right! I rarely have call to use my Weller D 550; months go by between uses but it is always good to go right out of the box. Now that's I've bragged on it, the next time I use it it'll probably be deader than a tombstone! :D

Paul Alciatore
02-14-2013, 09:07 PM
Make sure the nuts that hold the tip on are tight. I have had similar problems in the past and traced it to that.

Absolutely! Those nuts that hold the wire tip in place MUST be very tight. You should distort the copper. If a replacement tip is old, clean it with a bit of extra fine sandpaper before installing it.

I have a Weller gun that is at least 40 years old and it is still going strong, so they are not junk.

Another common problem is erosion of the tips. The solder will dissolve the copper of the tips so they commonly become thinner with use, usually just behind the formed tip where the corners are sharpest. The cross sectional area of copper is reduced and the resistance goes up. This causes less current to flow and little or no heat. The only solution is to replace the tip. I gave up on the OEM tips and form my own from 12 gauge solid copper wire. It is dirt cheap, even essentially free if you do any electrical work, and the tips formed with only curves, no sharp corners, will generally outlast the OEM tips 3 to 1.

darryl
02-14-2013, 09:32 PM
I wouldn't toss it- those guns have their place. The tips are copper, whether plated or not. 14 ga copper wire will work, but you won't get full power. You will still get soldering temperature- with 12 ga you will get full power. Things change as you lengthen or shorten the wire. A short piece of 14 ga will give you power, and a longer piece of 12 ga would lessen the power. A very short piece of heating element wire will get red hot. I guess you could use that to light a fire-

You can form a tip into any shape that suits the job you need to get done. You can hammer the end of the loop to make a sort of blade, and you can wind a few turns to look like a spring- this is useful to demagnetize screwdrivers, etc. You can also use one of these guns as a resistance soldering tool. Each terminal gets a short piece of heavy gauge copper wire which is coned on the end, but there's no complete loop. The two ends are bent to be close together, and in use you make both tips touch the thing you are trying to solder. Most of the heat is generated in the join, so in the right applications it works well. You could hold the trigger on and the gun won't overheat until you touch the two tips and complete the circuit- then the gun is back in it's duty cycle mode. I think I recall the duty cycle being 20%- 1 minute on, 4 minutes off.

As mentioned, these are very basic tools- a transformer with a 1 turn secondary. Barring bad switches, broken wires, and open windings, there's virtually nothing to go wrong. The tip connections would be the only snag in this. It's common to find that even with the screws tight, the connections aren't made well enough. You would do what you have to in order to get real metal to metal contact. Feels tight and looking good are no guarantees that the connections are actually secure, low resistance connections.

By the way, if the gun is not drawing power on one of the switch positions, you won't be fixing it by messing with the tip. If the one position seems dead, there will be no heat whatsoever on the tip- and on the same hand if the tip does heat somewhat on what appears to be the dead switch position, then the transformer is good, and the problem would most likely then be with the tip connections.

Final comment- a properly working gun will heat to soldering temperature in about 5 seconds. If it heats, but takes longer, then it's a tip connection problem.

lynnl
02-17-2013, 03:47 PM
......
The nuts are 3/8, I think, and I got one of those copper flare nut wrenches to tighten them with. It doesn't round the flats of the nuts as badly.

I use copper wire in 12 or 14 gauge for a homemade tip in a pinch--it seems to heat quicker since the wire is smaller gauge than the regular tips. I even flatten the wire in the middle where I use it to solder!



That was a splendid idea! I made up several tips of 12 ga copper wire, and they seem to work immensely better than the tip provided with the gun.

I think my real problem though was, as most everyone mentioned, poor connections on the tip prongs. This model uses two setscrews to bear on the prongs, as opposed to nuts. Even with a flashlight and magnifying glass I could not determine exactly all the features of the screw heads, owing to the shine and glare. They have shallow slots for a flat screwdriver, but it was still hard to get a grip on them. Likewise with a philips head driver. I suspected they also accomodated square-drive bits, but couldn't find any to fit.
After going to Lowes and getting some square-drive bits, I was then able to really crank down and get a tight connection. All is hunky-dory now.

GNM109
02-17-2013, 09:37 PM
I had to throw out my 100-140 watt Weller a few years ago. It never really worked. It wouldn't melt solder in any noticeable way.

I replaced it with the large one, something like 200-300 Watts, IIRC. This one really works. I had a previous large one that lasted more than 40 years before it burned out.

With Weller, bigger is better, I guess.

taydin
02-18-2013, 04:43 AM
I bought my weller soldering gun 25 years ago for electronics work. But soon realized that with the standart tips, it is running too hot. Burned out the solder and quickly corroded the tip. So I had thrown out the standart tips and was just bending tips from 2.5mm2 single piece copper wire.

But for the last 10 years, I am using a SMD soldering station for electronics and the weller is only used when mobility is needed to do electric wiring stuff in my shop.

ptjw7uk
02-18-2013, 05:01 AM
Another use for the Weller is to melt and repair plastic items, just run the power through a variac to adjust the temperature and your good to go. Makes a mess of the tip so have some spare.

peter