“The street finds its own uses for things.”
William Gibson
I am super glad that I personally didn’t post this to the web, or anywhere. The liability issues are astounding, and I don’t think an American company would have ever risked it. Our major manufactured product is lawyers.
I am not the source of this information, I take no credit for the ingenuity or blame for the danger. DO NOT TRY THIS AT HOME. DO NOT TRY THIS ANYWHERE. I AM EXPLICITLY CAUTIONING AGAINST IT FOR SAFETY AND HEALTH REASONS. YOU HAVE BEEN WARNED! THIS SORT OF THING IS EXTRAORDINARILY FOOLISH, AND IS PROPERLY ONLY THE PROPER PROVINCE OF EXTRAORDINARY FOOLS.
That being said, I’m also very glad to know this. I’ve tried to avoid working with SMDs and been fairly successful, so far, so I haven’t had a constant need that justifies a large expense in equipment.. but there are always potential exceptions, and the day is rapidly coming when it will be the rule rather than the exception. This is the first time I’ve seen something that will accomplish this in a post-apocalyptic cyberpunk scrounging scenario, or just where and when money is really, really tight, or, I dunno… you have a desperate need to de-solder surface-mount devices in a campground or junk yard.
I love the folks on Adafruit and have enormous respect for what they’ve done, but hey, sometimes you have to do something that the kiddies shouldn’t be doing, or in a way that they shouldn’t be doing it. Don’t think you’re going to see tutorials on how to do THIS anytime soon.
“I am endeavoring, ma’am, to construct a mnemonic memory circuit using stone knives and bearskins.”
Spock, The City on the Edge of Forever
Okay, obviously there are shock hazards here, and burn hazards here, right up to setting fire to the building you’re in. And eye damage hazards here. And toxic fumes.
What could possibly go wrong?
The attraction, for those foolish enough to consider it, is that hot air de-soldering stations cost hundreds, or at least $150 or so even if you find a deal on used or surplus. They are also bulky and not all that safe even with their industrial designs. They’re also not that trivial to control, using air convection as they do, heat goes everywhere.
Would this also work, with SMD soldering paste, for soldering? I can’t see why not.
Judging by the video, aside from being very, very dangerous in at least three different ways and probably more, this seems to actually work very well for very little money, and it fills a very real need (otherwise nobody would have been nuts enough to try it).
Okay, say you use a 65-watt bulb at 16 volts, obviously you need over 4 amps nominal, call it five. You could use it at 12 volts (or about 13.7 nominal for a car battery), but the video makes it clear that 16 works better/faster. A quick search on eBay turned up a number of possibilities, including a used Lenovo laptop power supply rated at 16v 7.5a, which seems like a nice margin, for $15.
“Tony Stark was able to build this in a cave! With a box of scraps!”
I’m very thankful for the video, but… honestly, alligator clips? That pretty much is what you’d do in a cave with a box of scraps.
So, what could be done to make this safer? The sockets for this kind of lamp are easily available, so we could certainly create a socketed mount with nice, flexible silicone-insulated wiring so the cord is not fighting you. Maybe some sort of insulating pistol grip with a trigger switch, and something fabricated from large aluminum tubing to keep hands or surfaces from contacting the source of heat.. or maybe build something into a gutted, broken and/or cheap heat gun, $10 from Harbor Freight? That gives you a heat-resistant tube with pistol grip and switch assembly.
As far as I know, all automotive halogen bulbs have that silver tip to keep there from being a brilliant pinpoint of direct light at the center of the beam blinding oncoming drivers. That’s sort of unfortunate for our purposes, and my first thought was to wonder whether halogen bulbs designed to work off of AC mains would work better and be simpler… but it may well be worth working around the limitations of the auto bulb to avoid the hazards of dealing directly with mains voltage. Plus which there’s some advantage to being able to use an auto battery, it gives some degree of mobility and the possibility of taking the operation outside to further limit risks. So, okay… using the auto bulb with the internal reflector means the light is coming out at a right angle, which may mean that the lamp and socket needs to mount from the side of the device tube, or underneath.
Some sort of adjustable aperture would be very helpful, something conceptually like the blinders on theatrical lights to shape the beam into a square or rectangle and make it much easier to localize the heating on a circuit board. Probably reflective baffles rather than black, which is going to get dangerously hot very quickly. In this use, in this heat range, you’d have to be very careful about materials.
Maybe not. I have a feeling that the scale is wrong. Look at the proximity of the bulb to the work in the video. We need a pencil here, not a gun. Still need a decent handle, protection from heat and shock.
Lots of food for thought. I love it.
— Robert the Wombat