View Full Version : cold heat soldering tool

12-27-2005, 01:43 AM
Played with it for awhile. It works, has some characteristics to get used to. It's a resistance soldering tool, so it relies on conduction through the joint to make the heat. The tip is basically carbon rods closely spaced to be able to bridge a wire or pc trace to get the conductive path established. In that regard, the tip itself doesn't have to get hot to melt the solder, but I believe the carbon does heat and aid the soldering process to some extent.

It works best with small junctions, and as you can imagine from such a tool, there isn't a glut of power available to heat something of any considerable mass. It would be hard pressed to solder an 18 ga wire crimped around a terminal, for instance. But for mounting parts to a pc board, it seems to work fine. Solder doesn't blob up on the tip, which seems to stay clean.

Proper soldering involves watching and making sure the solder flows on the pc trace and the wire being connected to it. Traditional wisdom says to heat the joint and let the joint melt the solder. In this case, the tool operates more readily when solder is first melted at the tip, so you do have to watch what's going on with the joint. Without that little dab of solder first, you have to manipulate the tool until you get a good conduction between the electrodes. A red led lights to show when this has happened, so at least you know when there's heating going on. Sometimes this 'manipulating' will cause you to use extra pressure on the tip, and there's a warning about that in the instructions.

I've been learning how to solder for decades now, so it came easily for me to use this soldering tool. It basically comes down to knowing when you've got enough heat pervading the entire junction. This tool doesn't apply heat to the junction, it makes the junction heat itself, using the solder as an aid to do that. The main limiting factor is the size of the junction. For normal components, great. For ic pins, great- with one warning. Because there's voltage across the two electrodes, you could conceivable apply that voltage across two ic pins, and some electronic parts will definitely be damaged by that. In general use, you'll always have to have that foremost in mind, since it's unlikely you'll know when it might be 'safe' to accidently apply that voltage across two pins. This thing applies the full battery voltage to those pins, so with fresh alkalines, you have over six volts there. It's safe to say that you'll be able to destroy gate protection diodes, semiconductor junctions, and input circuitry with this soldering tool. You could pop an led in no time this way, same for a transistor junction. This is going to be my major issue, and I'm declining to recommend this tool for this reason alone. To be safe, any user will have to either heat just the trace, and let the solder flow from the trace to the wire, or just the wire, allowing solder to flow onto the trace. Even then there's no guarantee that you haven't damaged something. If one part of the tip touches the wire, and the other touches the trace, you could have a conduction path through the trace to another pin, and damage could be caused instantly. What a heartbreak this could be for someone trying to get their own circuit working, or even trying to repair a circuit, not knowing if you're causing other damage.

Damn! This is not the glowing report I would have liked to deliver. This was a gift, and now I don't want to use it. She who bought it for me will want to know how it is- do I tell her it's basically good for destroying components? Anybody else own one of these? I'd like to have some feedback.

12-27-2005, 03:48 AM
I bought one and was forced to take it back. I am no soldering or electrical expert, but I have soldered small wires on circuit boards through careful application of heat with a small iron. I thought that this would be just the ticket for the occasional small joint so I wouldn't have to get out the iron and wait for it to heat up. In my experience with it, they should call it "No Heat" because I could barely get it to melt the solder. I don't even think I had one successful joint with it. I found it easier to just be careful with the iron than try to become an expert with that piece of crap. So I took it back to Radioshack and told them why. Also, I had never considered the point you made about it damaging components because of the way it works, good observation on your part.

12-27-2005, 03:58 AM
Darryl, I just bought one in a package deal of 2 25 watt irons, solder, head magnifier, and the Cold Heat. The guy said in his ad said that he couldn't get the C Heat to work, so for 15.00 I just had to Acquire it! He's right, it won't work. Put in new batteries, but the red LED doesn't even come on. I kinda look at it as a project to fix one of these days, maybe someone has a schematic for this MIRACLE TOOL! I can't really say if it's good or not; looks easy on TV though!

Dave da Slave

Steve Stube
12-27-2005, 04:16 AM
darryl, not everything deserves a glowing report. I think you made a fair and honest review which saves me money and time - for which, I thank you.

12-27-2005, 05:44 AM
I got one and melted the White plastic that holds the Tip in.I was tinning wires.

The tame Wolf !

12-27-2005, 05:53 AM
IT SUCKS! got one on sale at Harbor Frieght. It wouldn't heat even with 3 changes of batteries. Also the tip chipped and that was that went to RS bought a new tip for around $10.00 for a $14.95 tool planning on putting it on my sale table at names this coming year. Your report is right on. all TV hype.

Been there, probally broke it doing that

Your Old Dog
12-27-2005, 06:01 AM
Can those of us who didn't get sucked into one of them stand up and take a bow http://bbs.homeshopmachinist.net//biggrin.gif http://bbs.homeshopmachinist.net//biggrin.gif

When I look at this kind of stuff I do so with the knowledge that "you can't get out of something more than which you put in". So, if it's gonna melt solder and I can touch it with my fingers 1 second later it seems to me a lot of energy would be lost somewhere. The tip being as small as it has to be to operate on penlight cells it could only work on extremely light wire.

My friend bought me a real nice soldering pen for Christmas 25 years ago. It is a joy to use. I just have to remember to plug it in before I start working on anything. No free lunch where energy is concerned!

I was thinking of buying me one of those "Salad Shooters" but can't find them in the stores anymore. Any ideas?

Darryl, nice report, you probably saved a lot of us some money. I'd tell your wife how it went. Better than her never seeing you use it. I like being able to tell my wife how well the tools work she buys me as it brightens her up and encourages her to "think tools" instead of "cloths" for gifts http://bbs.homeshopmachinist.net//biggrin.gif

[This message has been edited by Your Old Dog (edited 12-27-2005).]

12-27-2005, 07:30 AM
My wife likes to do some jewelry work, and recently acquired one of the Cold Heat soldering devices. I was pretty skeptical when I first saw the thing, but I figured I'd give it a try. My skepticism was well founded, as it was pretty much useless. She returned it for a refund. She got to keep the free wire stripper that came with it though, and she gave it to me. I took it into my shop and gave it a try. It broke on the first wire I tried it on. I wonder if part the manufacturer's business plan is to rely on the consumer being too lazy to return these things?

12-27-2005, 08:26 AM
wish I had read this thread before buying on as a gift. Oh well still got the receipt

12-27-2005, 12:02 PM
X39 you are right you win. Whe I was making and selling clown props and magic tricks mail order and the shows. my catalog had a refund coupon in it for the two bucks it cost in 15 years of offering it. only got 2 of them back. both from the same type of people, thinking they some how shafted me by bringing the back. I use to ask people why they didn't send them back with thier orders. Thier answer was well yopu have those easy magic trick printed on the back of the two dollar bill! I would ask them well They don't have copy machines in your neighborhood. They would look puzzled and then start laughing. I probally made more money off the catalog sales than the sales from the catalog. LOL

Been there, probally broke it doing that

12-27-2005, 01:42 PM
Thank you, Thank you, Thank you:

I was just about ready to call up and buy one until I read this post. You saved me a lot of time and possibly grief. This is a good forum.

12-27-2005, 01:51 PM
You know, you could try some nicad batteries, they will put out a lot more amperage than alkaline will.

12-27-2005, 01:58 PM
Dang! And I got one of those for my brother. I'm glad he lives out of town. http://bbs.homeshopmachinist.net//biggrin.gif

Steve Stube
12-27-2005, 02:10 PM
CCWKen, exactly, I'm glad I didn't give one as a gift because my buddies don't live far enough away that the payback wouldn't reach me.

12-27-2005, 06:57 PM
As far as using nicads, they will put out a lot more amperage, but this 'pen' has a limiting factor based on an internal resistor. This resistor drops enough voltage to light an led when current is flowing. I doubt an ordinary battery would work in this tool, but a nicad would be overkill, and would probably not work quite as well because the nicad doesn't produce as high a voltage as the alkalines. Of course, a few soldering operations and the alkaline's voltage is going to drop anyway. At any rate, the tool doesn't rate having nicads used in it.

This brings me back to the Wen cordless soldering tool. It used a normal tip, normal in the sense that it got hot and then you used it. That tool had two nicads, so the tip ran from about 2.7 volts. Because this cold heat tool has a pair of contacts at it's business end, a person could make up a tip that would run on say, 5 to 6 volts, and it could become a more normal soldering tool. But first you'd have to find a suitable tip material, then do the math and make up a suitable coil, embed it in the tip- oh, never mind, it's too much work to be worth it. You'd have to instal a microswitch in the thing also, then there's the internal mods- not worth it. At best it would make an ok led flashlight for those willing to make up a tip with either two or four led's in it. Change the label to read 'Cold Light'.

I made myself a resistance soldering tool many years ago, but it only put maybe half a volt at the tip. It was still a bit tricky to get the tips both contacting the junction so heating could take place, but it was safe to use. It actually had a trigger that would bring the tips together like a needle nose pliar, so you could pinch a junction with it. It worked well enough, but the pair of wires leading to it had to be heavy gauge, and it was awkward. I didn't use it for very long, and it really wasn't the thing for pc boards. Pretty hard to beat the temperature controlled tip ala Weller and others.

The fuel powered catalytic tip wasn't bad either, I think I still have that one. It went through a ton of splicing during the older days of C band satelite systems.

[This message has been edited by darryl (edited 12-27-2005).]

12-27-2005, 07:29 PM
I was wondering if those things worked,now I know http://bbs.homeshopmachinist.net//biggrin.gif

Any comments on the "Magic bullet" food processor? http://bbs.homeshopmachinist.net//biggrin.gif

12-27-2005, 07:35 PM
<font face="Verdana, Arial" size="2">Originally posted by wierdscience:
Any comments on the "Magic bullet" food processor? </font>
LOL! I actually saw a guy this past May fishing with a "Popiel Pocket Fisherman". I asked him about it, he said he found it while cleaning out a garage.

12-27-2005, 07:56 PM
Yeah, and on the commercial they show a guy soldering something and then touching the tip to demonstrate how the tip cools fast making it "safe". I tried it and, yup, I got burned. Being a glutton for punishment, I tried it several times and it does not cool down as fast as they say.
I was also disappointed in the performance. Luckily, I was using one my friend owns and did not waste my money.

12-28-2005, 07:49 AM
Have you seen the cordless solder irons in the Micro-Mark.com catalog? $40-60.00 each ,but these guys would beat the Cold Heat POS. If anyone has one, like to hear your reviews!

Dave da Slave

12-28-2005, 08:02 AM
When I first saw that cold soldering iron I thought to myself, "Yep! That's going to be this Christmas' replacement for the Roto-Zip!" It looks like I was right!

I'm still wondering what to do with that stupid Garden Weasel my in-laws gave me a few years ago.

The titanium colored plastic flashlight I got from them 2 years ago went into the trash a few days after I got home with it. I couldn't give it away to anyone at work. They just laughed at it. My mother-in-law swore it was really made from titanium. http://bbs.homeshopmachinist.net//smile.gif

I could go on...and on...and on about the gifts they've given me.

I told my wife when she went to visit her parents that if they were giving me a cold soldering iron for Christmas I wanted her to throw it in the trash on the way home. I'm really surprised they didn't give me one.

[This message has been edited by pgmrdan (edited 12-28-2005).]

12-28-2005, 08:11 AM
I use the Black and Decker cordless butane irons. I bought two of these years ago. I don't know if they still make them but both of mine still work fine. They have to heat up like a regular iron of course but they have enough heat to solder automotive wiring and use disposable propane cartridges that are also used for cordless curling irons. They run for hours on a cartridge.

If they don't still sell them it's too bad. I have tried many different cordless irons and torches over the years and these are the only ones that really work as reliably as a plug in iron. The only consideration is one that applies to all butane powered tools. They don't work above about 4000-5000 feet altitude because the mixture becomes too rich and isn't adjustable. Butane has a really narrow range of proper mixture.


J Tiers
12-28-2005, 09:59 PM
<font face="Verdana, Arial" size="2">Originally posted by GM69camaro:
Yeah, and on the commercial they show a guy soldering something and then touching the tip to demonstrate how the tip cools fast making it "safe". I tried it and, yup, I got burned. Being a glutton for punishment, I tried it several times and it does not cool down as fast as they say.

Saw several of the ads, in my annual "watch television after coming in from the shop" visit to the in-laws (normally never watch).

I looked at that ad closely, since I saw it about 10 times, and if you noticed, the demonstrator was mighty darn quick about melting the solder so it wouldn't be very hot on the finger.

And as far as repairing jewelery.... your jeweler won't thank you for "poisoning" the joint with "soft solder" after you don't get it fixed and have to take it in to him/her......

12-29-2005, 01:57 AM
Wow. Sure found a lot of -- stuff while looking for my catalytic soldering pen. It's true what they say, you always find it in the last place you look.

This one is called 'Portasol'. I'm not sure who made it, possibly Unger?. Looking at it now takes me back out in the field splicing wires. Memories.

Aha! Found my homemade one. Need to charge batteries so I can take a pic and post it.

Your Old Dog
12-29-2005, 05:22 AM
<font face="Verdana, Arial" size="2">Originally posted by wierdscience:
I was wondering if those things worked,now I know http://bbs.homeshopmachinist.net//biggrin.gif

Any comments on the "Magic bullet" food processor? http://bbs.homeshopmachinist.net//biggrin.gif</font>

Is that a new Smith and Wesson 44 calibre round? http://bbs.homeshopmachinist.net//biggrin.gif

[This message has been edited by Your Old Dog (edited 12-29-2005).]

Paul Alciatore
12-29-2005, 08:09 PM
If you want a recomendation for a good soldering iron, it would have to be the Weller WTCP model. I bought one almost 40 years ago because the TV station I worked for had one on the workbench that never quit. I figured if it lasted several years in that shop with everyone using it, it was pretty good. Mine is still going strong with the original tips. And it is great for temperature control as each tip has internal regulation.

Mine cost about $45 in the 60s but I believe they are well over $150 now. I could have purchased six or eight irons and dozens of tips by now if I had choosen a cheaper model. swould have cost 3-5 times as much. Quality tools are cheaper in the long run. TV specials are usually total c***.

Paul A.

12-29-2005, 09:06 PM
I have the Weller WTCP that I got in Africa in '70. Still works, though I had to swap the transformer for a 110 v one when I came back here. I have changed tips about 3 times since then, and I've also made some custom brass and copper tips and pressed the sensor stub onto them to keep the TC part working.

I got about 20 yrs out of the original tip, and the replacement tips haven't been as good- don't know why- they should be the same. It's had lots of use, mostly as a soldering pen, sometimes for desoldering, and sometimes as a chisel. I wore through the plating I think, and it's probably through the desoldering that it wore out.

I still have and use almost daily the 150 watt version of it. That's a straight 110 v model, no transformer or base. The original I believe was a 40 watt.

I also have in my 'collection' a 3 dollar one, mostly because I couldn't believe that you could buy a working soldering iron for 3 dollars. You get what you pay for, of course. In this case, the tip is crap, no heat control, and worst of all the cord is only about 2 1/2 ft long. Have to admit, I used a four letter word when I saw that, but hey- I bought it didn't I. Duh

12-30-2005, 08:03 AM

Ya know, the other day, I was working on my 87 Chevy pickup, trying to get the 350 out. For some reason, every bolt I pulled got its head rounded off. I'm not sure what was wrong, I was using a brand new perfect crescent wrench to do it with.

Now, you guys are gonna read that and tell me, well you dumb ass, you didn't use the right tool for the job, ain't ya.

Well, guys, that Cold Heat solder iron is a tool also. The shop at work as 2 of them, as the boss lets us use his. We're not out there doing automotive multi-strand 0-18 Ga. soldering with it, no, it won't do that. I does work perfectly for wiring up the stuff in a rack of computer/audio broadcasting equipment in a radio station. I built a studio's worth of wiring with one last week and it worked perfectly, every time it was tried.

It took a little bit to get the technique down on how to do it, once that was done, it was a real joy to use. The 'cools off quickly' thing is true, for the most part. The point of that is the entire GD iron isn't 900* all the farking time. I can set the thing down on the bench and not worry about it burning through, I don't have to worry about catchin the iron's cord with something and pulling it out of it's base, burning something else. You can throw it in yer pocket within 30 seconds of using it without any worry at all.

This thing isn't a be all-end all soldering iron, that is not it's purpose.

You all have cordless drills, hows come I don't hear you whining that the damn cordless DeWalt won't put a 3/4" hole in 1" plate? Same principle

12-30-2005, 05:45 PM
Here's a real man's cordless drill. http://bbs.homeshopmachinist.net//smile.gif


12-30-2005, 06:17 PM
54 FRIGGIN DOLLARS! No thanx,I will keep my Dewalt.

The tame Wolf !

12-30-2005, 06:19 PM
Good Grief!!! 55 bucks for THAT??!

12-30-2005, 06:56 PM
I was laughing even before I checked out the pic, then I laughed even more. I've pinched my fingers in one of those more times than I care to remember. Dad had one. It might even have been a Dewalt.

12-30-2005, 07:59 PM
LOL! I hate to admit it, but the only "cordless" drill I own is of the type in the link. In fact, I have two of them.

12-30-2005, 08:32 PM
That drill is what we used for the first two months of airframe repair school training.

12-30-2005, 08:46 PM
<font face="Verdana, Arial" size="2">Originally posted by Evan:
That drill is what we used for the first two months of airframe repair school training.</font>

They gave us worn out 3/8ths" air drills to work with when I went to Airplane school.