How to Make a Simple Lava Lamp

Select a bottle before making the stand to hold it. Get one with a screw-on cap. A one-gallon clear wine jug would suffice; however, something narrower would be better. The bottle needs surface area so "lava" that floats to the top can cool off, contract and sink again; otherwise, the "lava" stops flowing.

Cut a hole in the bottom of a thin-walled aluminum pot. A circular saw with a steel blade should work and be faster than a handsaw or nibbling tool. A square hole would be faster to cut than a circle. Keep in mind to make the hole small enough that the bottle won't fall through.

Purchase a manual wall-plug dimmer, so you can adjust the intensity of the bulb to the temperature that gets the lava to flow. Screw the 40 watt bulb into the bulb socket and place it under the upside-down pot. Plug the other end of the socket wire into the plugged-in dimmer.

Fill the bottle one-eighth or less with mineral oil. Then fill the bottle three quarters full with 75 percent rubbing alcohol. Let the mineral oil resettle for half an hour. If the pouring really jostled a lot of small bits of mineral oil loose as small blobs, you may want to let it settle for a few days. Place the bottle on the pot so the bulb heats it for half an hour or more.

Add 90 percent rubbing alcohol in small amounts every 10 minutes, giving it time to diffuse throughout the bottle. Do not shake the bottle to speed up the mixing. That will cause the mineral oil to break up into small blobs and you'll have a harder time knowing when you've achieved the density balance between oil and alcohol. It can take days for the small blobs to settle out. If the mineral oil is still not rising to the top yet after reaching the 7/8 mark, start adding distilled water in small amounts every 10 minutes. If you fill the bottle up to just an inch left of air at the top, use a turkey baster to suction some of the alcohol mixture out. Replace it with some distilled water. Wait 10 minutes and repeat. Eventually you'll achieve the right balance and the oil will float to the top, cool down, then sink back down to the bottom. Once you've achieved this balance, you can screw the cap back on.