Step 8: How not to

You've watched the video, you saw the inferno. That was caused by double-whammy of not paying attention and using inappropriate materials being used. Using insulation is sound, provided it's rated to be used in high-heat situations. In my effort to keep things accessible and open I chose to use a rigid-type foam building insulation. Bad idea. The heat from the crucible in combination with the duration I had set caused a corner to the foam to ignite. I shut off the microwave and waited to the flame to die out, but it was only getting worse. Fearing a backdraft if I opened the microwave door, I risked it anyway. Yup, huge fireball.

We were able to get our cameras running just when the flames died down from reentry temperature to just immolation inferno. 
The lesson here is to use just bricks to create the hearth and wait the amount of time required to to the job effectively, without trying to accelerate the process with insulation.

Science can be messy and dangerous, so be safe and have fun!
jscanlan5 months ago

Interesting experiment. I agree with Void Schism comments, I was wondering if it was going to get more exciting with the water put on the electronics. There are some low temp casting alloys out there that may be interesting to try out.

67spyder3 years ago
I applaud Mikeasaurus for including the failure as well as the success. Sometimes we learn more from failures. Plus it will stop someone else from from trying it.
lasersage3 years ago
All these people worrying about lead poisoning and yet nothing about the fumes from the building foam :)
I'd be more concerned about breathing that.

Have any of you ever read

there is a fantastic article about smelting Zamak. Its Zinc, because of its low melting point, with Aluminium (and a touch of copper) dissolved in it.
Makes for a very useful alloy for casting, but can be made at relatively low temperatures.
The next candidate for microwave smelting?
SIRJAMES093 years ago
there are too many things that can go wrong in this instructable....lead is deadly, silicon is equally as bad....I can not & will not support this instructable.

The risk to life and/or limb is too great.

They need to pull this instructable.
"all it takes to kill a show forever, is to get one episode pulled. If we convince the network to pull this episode for the sake of Muslims, then the Catholics can demand a show they don't like get pulled and then people with disabilities can demand another show get pulled and so on and so on, until Family Guy is no more - it's exactly what happened to Laverne & Shirley. " -- Cartman

Take this quote and reapply it to Instructables. I think you will see why a site cannot pull this instuctable. As soon as it is pulled then nothing can stop people from pulling any instructable that may be deemed to dangerous of has the potential of being used for illegal ends. Next thing you know the site is empty and user-less and the DIY community is devastated.
I suppose you're right....

My apologies.
Don't be too sad, we all make mistakes. I was just in a trolling mood.
and I get a little upset about internet censorship.
s52e363 years ago

I dunno, I think it would be much more effective to use magnesium instead of the bricks, and some thermite to get everything up to the appropriate temperature...

And while I think that would be a very interesting experiment it's also very likely to create a fire that will probably kill you. 'specially if you throw water on it.

Anyway, I think this is a great project, and if there was some way to do this repeatably and safely with a cheap-o microwave I would totally sacrifice my old microwave to science.

If you want to stick with solder casting, I recommend just picking up a cheap-o solder pot for around 40 bucks. Does the same thing, without the flames. Of course it's not nearly as cool.

I would like to see you do bronze next. Either making it as an alloy of copper and tin, or just finding a chunk of bronze and making it into something cooler. There is no better way to learn science than by doing it, and I applaud you
Wildrat3 years ago
good instructable.
If all the cave men sat around a pile of wood discussing what the discovery of fire could cause, for example forest fires, house fires or cave fires we would never have been able to have weenie cook outs because of weenie heads worrying about every thing that could happen. Fire would not have been discovered or used and all the cave men would be sitting around a wood pile eating raw pork, beef, and mechanically separated chicken and turkey! Yummy!
Actually they would be sick from the pathogens carried by their raw meals, and of course man kind would have never developed the ultimate cooking method, the Barbecue!

As Miss Frizzle used to say, "Take chances, make mistakes, get messy!" How on earth are you ever going to learn anything if you don't!!

"The only perfect sight is hind sight" and the only way to get that is to do!
79spitfire3 years ago
And once again we have the perfect examples of why no one wants to try or create anything new or different!

Great job for having the cahonies to try something 'out of the box' (or microwave as it may be)

As to the insulation I would suggest trying to score some refractory bricks, they can be had at ceramics suppliers, and cut easily. You may have some luck chatting them up, and getting some fractured or broken ones to cut up.

I'm not a fan of using solder, as much of it can contain fluxes, and it can be pricey. Old (lead) tire weights can be used. Silver might be another possibility, but also can be pricey.

Before we have ANOTHER tirade about how bad lead is, please keep in mind that lead has been used for casting for thousands of years, and while it is very toxic when ingested, or inhaled, simple safety precautions will protect a casual hobbyist.

Remember it is YOU who is responsible for you safety, not someone who is trying (at his own risk) to create something new!
moon1613 years ago
Yes, I'm irked about the molten metal and chemical hazards here. It seems safer to do it on a gas range in the kitchen, or over a propane burner outside.

I'm sure there's a disclaimer that absolves the site of responsibility for accidents somewhere, but I'd get someone on staff with a background in industrial safety. Having an instructables staffer cook this up doesn't help the site image.
hogey743 years ago
Maybe its just me but the more warning comments on an instructable, the more I want to do it! Especially if there is the risk of fire and/or explosions lol. I am taking all these clearly well meant warnings seriously BTW.
bonpierce3 years ago
You do realize this contains LEAD right? Lead is a carcinogen whether it is being melted or held in your hand a a charm or around your neck as a necklace.

You don't want long exposure of any kind to this stuff. Seriously.
Void Schism3 years ago
Worth mentioning to anyone daft enough to try this without a decent knowledge of fire safety:

Clearly the power was disconnected and the metal had been removed, right? (nod convincingly)

wetting electrical fires can result in electrocution and pouring water onto molten metal can cause steam burns, expolsive thermal stresses and molten metal spray.

Get a CO2 extinguisher and keep it to hand. A bucket of sand is also a good idea for those "why is it still burning... oh #@%& itsathermitreaction!!!" moments

Have fun, be safe and if it blows up post photos ;)