Is it safe to dismantle home electronics?

My kid loves playing with “adult” objects and taking things apart to learn about what’s inside. So, we bought some ancient (70s-90s era) consumer electronics at garage sales, for him to dismantle and mess around with.

So far, we have telephones, a walkie talkie, a tape recorder, and a small (4" screen) combination TV/radio. The batteries and power cords have all been removed. We’re likely to get some defunct power tools (nothing sharp), small kitchen appliances (ie. hand mixer), printers, a vcr, etc if he’s really into it.

What hazards should we look out for? Anything seriously sharp, poisonous, explosive?

What precautions should we take? Gloves, goggles, a fire extinguisher?

Are there any items that should be excluded entirely? The TV worries me a bit, because of the evacuated glass tube, but I have no idea how dangerous it is.

No. Some things like TVs store electrical energy and need to be discharged before touching the interior parts. This is true even of the TV has been stored unplugged for a while. This isn’t something to experiment with.

How about one of those electronics discovery kits instead (various sizes, 100 - 750 pcs)?
http://www.amazon.com/Circuits-Extreme-SC-750-Electronics-Discovery/dp/B0002AHQWS/ref=sr_1_4?ie=UTF8&qid=1438116218&sr=8-4&keywords=electronics+snap+kit&refinements=p_85%3A1

Obviously, nothing should be AC powered, and probably not powered at all, as you dismantle.

The CRT in the TV is the vacuum tube risk you’re thinking about, but if it’s been plugged in recently, it’s also a shock risk. But not necessarily the existential risk people often think it is.

I think I dismantled my first CRT TV (B&W) as a young teenager, and got the CRT discharge shock. Obviously, it didn’t kill me, but it was frightening and painful, so probably good to avoid.

IMHO, though more of an “advanced project”, including proper discharge provisions.

What age kid?

Most of that stuff (with the exception of the TV) seems harmless. Probably the biggest danger is trying to get it open. A lot of consumer gear is glued or has concealed screws and you may learn some hard lessons about what happens when you lose your patience and start prying at stuff with a screwdriver. There might be the occasional sharp sheet metal edge.

Even though you’ve removed the AC cord, there might be the temptation to try to plug things back in and see if they still work. You’ll have to keep an eye on that.

I did have fun taking apart bits of electronics when I was in my teens. I still remember plugging in a old dictaphone and watching in horror as a large capacitor started swelling. Dove for cover just before the explosion.

Microwaves have a capacitor that can hold a charge for a bit. Not a big risk if it’s been unplugged for a while, but don’t take chances.

Some devices have really strong magnets. E.g., hard disk drives. You can get into a problem it the kid gets a couple of those and starts handling them.

Some devices have batteries hidden in them. NiCds are poisonous and NiMHs have an really bad chemical in them. Just about all of them can overheat easily when shorted and cause problems. Even the quarter-sized ones. Also, they are not all “battery shaped”. Some can be thumb-sized rectangular things.

And on and on.

In short, if you didn’t know that the CRT TV was a Very Bad Thing, you need to rethink what you’re doing.

Toxic and Hazardous Materials in Electronics (pdf file)

It lists the types of electronics where you’ll find them.

Wow, that could have gotten ugly. Thanks everybody.

Consumer electronics are booby traps. I’ll shuffle these off to the e-waste recycler and look into getting a commercially available electronics kit.

Here’s a youtube channel to watch (both for your kid and also for you as it’s quite entertaining, IMO):

Newer episodes are far more professional compared to the oldest ones. The youtuber takes apart all kinds of electronics and points out good & bad designs and why they’re good/bad. Also some stuff on how electronics works, the value of datasheets, math, and so on.

Don’t over-react. It depends a lot on the age /maturity of the kid.

IOW, if he’s young enough to still be putting random things in his mouth, probably half the stuff in your *kitchen *isn’t safe for him to play with unsupervised either. And none of this stuff is.

Other than the CRT the worst thing a 10-year old is going to do with the rest of that stuff is stab his thumb with a screwdriver. Which is excellent training for a would-be tinkerer.

A 15-year old who can’t mess with this stuff safely is a 15-year old so incapable as to be destined to be institutionalized for the remainder of his life.

So where’s the kid on this scale?

And definitely take away the CRT TV until he’s had more experience and is also a teen.

Christ. What a bunch of hyper-protective nonsense. Yeah, don’t let your kids leave the house at all, since there are dangers all around.

Reasonable precautions are all that’s necessary here. Capacitors are a minor danger and should be discharged before handling, though even there the danger is vastly overplayed. I was able to find exactly one news story of a man killed by a (microwave) capacitor. If he had followed any of a few basic precautions, he wouldn’t be dead.

LSLGuy has the right idea. It depends on the kid’s maturity level. But this stuff isn’t any more dangerous than things you would find in a kitchen or garage, or a swimming pool for that matter.

Abrasions, cuts, minor burns, etc. are the biggest “dangers.” Kids are gonna get scraped up learning stuff. Who cares?

I went through this and did the EXACT same thing as described in the OP. Only instead of yard sales, I found junk in the alley.

Dad gave me a lecture about capacitors and other dangers. I’m glad he did, and I never got hurt other than skinned knuckles and dirty hands. Good luck.

I’m actually laughing at this.

Oh geeze, your kid may be cursed with THE KNACK!!

Any electronics produced in the last 15 years should be made with lead-free solder so that not a problem (it never really was unless one eats a circuit board). I would be concerned with playing with picture tube TV’s. The glass tube can implode if cracked in the wrong spot and some capacitors can carry a significant charge. I would also agree with staying away from microwave ovens. Electronic toys and personal electronics are no problem. His greatest danger is probably stabbing himself in the hand when a screwdriver slips off a tight screw - but that’s how you learn.

When I was about 12 my parents gave me a Craftsman soldering gun and I was supervised at first. And I burnt my fingers. And I LEARNED. And then I could unsolder electronics and solder my own experiments. And melt and cut plastic. And create woodburning art projects. And then clean and tin the tip so I could solder some more. At twelve.

I was taking stuff apart like your son when I was 5-6 years old. It might be a good idea to get him some safety goggles “just like Doc Brown” so he can be a mad scientist. And if he tries to simply break stuff open he could get pinched by a plastic electronics case. Get him a few sizes of straight and Phillips screwdriver and some diagonal cutters for wire and turn him loose! :slight_smile:

Take those really strong magnets that ftg mentioned. Do you know what the biggest danger is from those magnets? It’s that, if the child swallows them, it can pinch parts of the digestive tract, causing perforations and other issues. Various magnetic toys have been recalled for this reason.

So the primary precaution against injury from magnets is to not let your child literally eat them. If that’s a real risk factor, then the child probably isn’t mature enough to disassemble these things.

Beyond that, rare earth magnets are a pinch hazard for children, but range of possible injuries is simply not significant enough to be worth considering. It’s like taking paper away because paper cuts are possible.

The greater risk here is that overprotective parents will create stupid, incurious adults that are incapable of distinguishing actual from imagined hazards, and unable to take reasonable steps towards ameliorating real hazards. Hands-on experimentation–with a degree of age-appropriate supervision and instruction–is the solution.

Absolutely. When he can disassemble a computer: then has a driver for the tamperproof fasterners on the hard drive: then knows how to remove snap rings, Then eats a hunk of metal the size of a cookie; you can worry about super magnets.

This.
I was disassembling TVs and stereos when I was 8 or 9.
Yes I have the knack.

Same thing with digital cameras. The capacitor that drives the flash can deliver a painful shock or worse.

I learned about capacitors the old fashioned way. I was playing around in an old point-to-point wired radio (no circuit boards) and got zapped.

You cannot imagine how confused I was, since the radio was unplugged. So, years later I went on to study electronics technology.

The kid is 3 and used to being around dangerous household objects. At school there’s a stove/oven and a clothes iron just sitting out for (supervised) use. He knows how to clean tables and mirrors and rugs with various spray cleaners. I could go on, but suffice it to say he’s capable of restraining himself when told something is dangerous.

The plan was to do this in a supervised way, mostly as an excercise in tool use and understanding the logic of how the parts fit together. Just getting a general idea of what the different pieces do, e.g. the electricity goes through these wires to the motor, which spins these gears to wind the tape.

The idea was to not mess around with the circuit boards, beyond disconnecting and removing them in one piece and maybe naming some parts. Desoldering things will have to wait until elementary school.

He’s thankfully past the foreign objects in mouth phase, so ingestion of toxic, magnetic, or sharp components is not a problem.

Pinching and cutting hazards sound minimal and controllable. Besides lead solder, is there likely to be anything else that poses a poisoning hazard through casual touching?

The TV is out, and no microwave ovens or cameras either. I realized the linked article was meant to show that CRTs really aren’t that dangerous, but there’s too much that can go wrong in amateur hands.

As for other shock hazards, which seem to be the big risk, we would need to look out for batteries and capacitors. Anything else?

To be honest, after perusing images online, I not confident I can identify and discharge or otherwise render safe every single component that might hold a significant electric charge.

Between that and the small but non-zero risk from lead solder, I’m going shelve this idea until he’s big enough to build robots or radios or whatever, then he can salvage parts from this stuff.

Any suggestions for safer, perhaps mechanical instead of electronic, stuff to take apart?