Jump to content


Getting an "Insecure Connection" warning for Exisle? No worry

Details in this thread

- - - - -

Soldering irons for everything but soldering


  • Please log in to reply
2 replies to this topic

#1 Orpheus

Orpheus

    I'm not the boss of you!

  • Administrator
  • 17,841 posts

Posted 08 December 2019 - 02:47 PM

Do you have a story about using a soldering iron? I want to hear it. Especially if it involves a use that God never intended, and is one of these Wrong-Sized (over/underpowered) units. My [first] story is in the next post.

First, The rant:

I've always done a lot soldering -- electronics, plumbing, metal repairs, car wiring. My 5th grade Social Science Fair project involved well over 200 solder connections  (Don't ask me why we had a Social Science Fair. As far as I recall, Dekalb County only held it that one year. I guess some Liberal Arts major in Administration got miffed at the popularity of Science Fairs in the Apollo era)

All my life (it's slowly changing), most soldering irons sold in stores were at least 40 Watts, often up to 150W. WHY? Those are always the Wrong Size!

I call them "wood burners", not because of wood-burning stoves. The one thing I've ever seen them be the Right Size for is: wood-burning craft work. Which is not soldering, so why call them soldering irons? 150W is woefully underpowered for plumbing [use a propane torch instead) or most metal repairs. 150W is barely able to craft stained glass, thin sheet metal work and jewelry, but I much prefer having more available power that I can dial down as needed. But why do they sell 100W? 80W? 60W? 40W is not bad for car wiring, but you rarely solder in automotive work -- and when you do, you're likely to upside down, barely able to squeeze your arm around a dashboard, frame or pipes -- an electric cord just makes it worse. I use a butane iron in cars.

You could do electronics with a 40W iron, if you're a bit careful, especially with the old thick through-hole components I grew up with. I used a 15W iron for electronics then, and with today's higher spec, lower power, smaller (often SMT) components, anything over 15W is just asking for burnouts left and right. (unless you're reasonably expert, in which case you can use anything from a wood match to a car battery -- and probably have, because your friends/coworkers expect you to get them out of the jams they get themselves into.)

Nowadays, USB-powered soldering irons are all the rage. Those were usually limited to 5W (pretty underpowered even for SMD) and often only managed 2.5W [a level of uselessness previously only seen in "USB fans" that could only "beat the heat" if it was the Miami Heat (basketball team) in a hockey game] but then the advent of cheap compact lithium cells and high-powere cellphone chargers ushered in an era of clear-thinking, where USB soldering irons were in the 10-18W range. Now? Well, we have a new USB standard, USB-PD, that will allow newer USB devices to supply up to 100W, and Cthulhu-help-me I'm seeing 100W USB soldering irons. As if we hadn't spent over half a century establishing that this is THE WRONG SIZE. Too powerful for electronics, too weak for much else. But hey "bigger is better". Numbers sell product.

Strangely, the most common use I see for overpowered soldering irons is shrinking heat-shrink tubing or tape. Then again, I see people publishing videos left and right where they unashamedly shrink heat-tubing with matches.

Don't ask me how a YouTuber who proudly selects The Right Size of heatshrink tubing from their assortment of 12 diameters in 8 colors hasn't managed to encounter a heat gun or even a hair-dryer in their life. Having come of age in the 1980s, I'm *still* picking random blow-dryers out of every nook and cranny of my house, car... teeth. They were like locusts or cicadas.

#2 Orpheus

Orpheus

    I'm not the boss of you!

  • Administrator
  • 17,841 posts

Posted 08 December 2019 - 02:47 PM

Every winter, the cold thickens the motor oil in my air compressor, which makes the motor overload on initial startup. If it starts, it's runs fine all day, because compressors generate plenty of heat.

In past years, I've kept the compressor in the kitchen or basement and either rolled it out as needed [awkward-- it's HEAVY!) or ran a hose to the garage and ran the compressor indoors (loud, and the long hose causes a pressure drop)

From time to time, I've idly thought that the real solution would be an engine preheater, like the ones diesel cars use in cold climates. I thought about using "gutter heater" wire to make a blanket or even using a cheap electric blanket, but that could take 30-60min to heat to the inside of the engine, and I was pretty sure I could make a cheaper built-in solution. I have plenty of nichrome ("resistance/heating wire") but I'd need to insulate it in fiberglass sheath, which doesn't seem come in a small enough size to sheathe a thin nichrome wire. Besides, as my Aussie friend Dave Jones would say "It seems a bit how-ya-doin".

Then it hit me: I only need to heat the oil, not the whole engine block. I grabbed an old 1960s soldering iron (at least 100W) off the shelf, and threaded the end so it could replace the oil plug on my compressor. It had a "plumbing tip" was about the right size to thread directly with a die.You could use an electronics soldering iron (usu 40W or less), but you'd probably need to make an adapter for the narrower tip. Just drilling a hole down the length of a suitably sized short bolt would work.

The heat capacity of motor oil varies, but it's generally in the range of 2 kilojoules per degree C pr kg, and a liter of motor oil weighs around 0.8 kg, so you need 1600 joules/L (1500kJ/qt) per degree. For my smaller compressor (10gal air tank, 1.5L of oil), this would translate to about 2 °C per minute -- but the metal oil sump will be cold, too, so it's more like 1°C/min. Fortunately, since my garage doesn't go much below the freezing point, I rarely have to heat the oil much more than 5°C (9°F) to get the motor to start, so 5 min of preheat (10 min tops) is all it takes. Beats the heck out of dragging the compressor or long/heavy  coils of hose out to the garage

A CAUTION: Air compressors (and some small inexpensive internal combustion engines) often operate on "splash lubrication". Instead of an oil pump, some small part of a camshaft or piston dips into the oil pan splashing oil up to lubricate the moving parts. The oil drain plug is is usually on the "far end" (way from the piston) or in the middle (under the motor), but if it's directly under the cylinders (withthe external heat sink fins), don't stick your soldering iron too far into the oil pan, so the splash paddle doesn't hit it.

Edited by Orpheus, 08 December 2019 - 04:36 PM.
Caveat


#3 Orpheus

Orpheus

    I'm not the boss of you!

  • Administrator
  • 17,841 posts

Posted 25 December 2019 - 08:14 PM

I can't believe I didn't remember this earlier. It's probably the #1 improvised use tool I've made in my life. I've made at least half a dozen for myself (It's often faster to make a new one than figure out where you left the old one) or for friends.

Homemade "pickle jar" smoke generator

I most often use these to find vacuum leaks in cars. You'd be amazed how often a few minutes poking around with a stream of smoke will locate a vacuum leak tht you can fix yourself in minutes, saving yourself $$$ in ineffectual dealership diagnosis time, unnecessary repairs that don't address the actual problem, and problems that get WORSE after a repair because the repair flexed or pinched the already damaged hose that was the real cause all along. Vacuum leaks can cause engine, transmission, air conditioning etc problems where every [other] part of the system is working just fine. Fixing a vacuum leak usually just takes a sharp knife and $1-2 of the right size hose -- maybe a $2 barb fitting, in some cases-- and takes a few minutes for any layman. Let your kids watch; they'll learn a life skill. It's that easy. Using a smoke machine has literally saved me/my friends enough to buy a whole car over the decades

However, a smoke generator can be used for a LOT of other things from pinpointing cold drafts (sorry, "draughts") at home to debunking seances (there are few famous historical examples)

MATERIALS:
A crappy soldering iron: You can get them for a buck or three at your usual discount sources. Cheap soldering irons are among my "order stuffers" when I needed an extra couple of bucks to earn free shipping in an online store like Amazon)

A couple of old cotton socks: Shredded T-shirts etc. will work too. But they must be cotton, not wool or synthetic. And don't be like my friend who used old torn underwear. The rubber in the elastic will create a huge stink (well, I'm assuming it was the rubber, but with old underwear, you never really know)

A few ounces of mineral/baby oil: Don't use "the real thing". Use a petroleum based oil, like Johnson's Baby Oil, not oil rendered from real babies.

A pickle jar: A 1 qt (1 L) pickle jar is the traditional container, but anything from an 8oz chutney jar to a clean 1 gallon paint can will work --anything that seals with a metal lid

A few feet of flexible plastic tubing: I prefer to use clear polyethylene tubing (aquarium tubing from a hardware store or Walmart; old nebulizer tubing; IV tubes, etc) but there's no real reason it has to be clear. You can cut a non-leaky section of an old fuel hose, garden hose,  air hose etc.

Almost any kind of sealant or glue


TO MAKE IT:
Poke two holes in the metal lid: one barely big enough to fit the hose through, and another big enough to stick the soldering iron through.Some people add a third hole for another tube so they can blow or pump air in to make a nice smokestream

Insert hose and soldering iron.

Seal with suitable glue or sealant if necessary. You want this  to be smoke-tight, but it's not going to be under any real pressure.

Stuff the socks into the jar or paint can, Soak with mineral or baby oil.

Put the lid on the jar/can: Make sure the soaked socks surround the soldering iron snugly. It's better if you remove the soldering tip from the soldering iron. You just need the barrel of the soldering iron in the jar, touching the soaked socks.

Plug in the soldering iron. The socks may smolder, but baby oil won't burn at these temperatures. You using the socks as a wick to draw the baby oil to the heat, where it will vaporize. As with kerosene lamps or birthday candles, the cotton wick may char, but it doesn't matter.It may take a few minutes to start producing smoke, but it won't burst into flame (not enough air). If you used an extra hole (and tube) you may want to block that off until you get a gook amount of smoke.

There are a lot of DIY Smoke Generator videos on YouTube, but I won't single any out. They all work. They just differ in the materials at hand, how fancy they wanted to make it, and what DIY techniques they were most familiar with (for, e.g. making, sizing, and sealing the holes.


BTW: you can also locate a vacuum leak by putting a hose on a cheap propane torch -- when you get near the leak, it'll suck the propane in (instead of air) and rev higher/smoother. But though that is actually slightly easier to do, many of my friends were willing to do the smoke method not the propane method. They fear what they know not.


0 user(s) are browsing this forum

0 members, 0 guests, 0 anonymous users