Couple of tips. For color, use aniline dye. I think it can be had for use as candle colorant. probably find it on sleazebay. You want a dye that mixes with the paraffin and not a pigment which consists of solid particles suspended in oil. Second, to adjust the specific gravity, look into gauge fluid. as in manometer fluid. It is available in specific gravities from about 0.5 to 4.3. These are chlorinated hydrocarbons but since they don't evaporate (if they did, they'd mess up the calibration of the manometer), there is no chemophobia concern. The 4.3 stuff is really weird. It has a viscosity similar to water but is so heavy that one might think there is mercury in the bottle.
Yes, those things that hang out in the set unceremoniously. Just doing’ their globular thing. Speaking of misnomers, unless the lamp has broken the lava is inside the glass so shouldn’t they be magma lamps?
These are important questions. Lava lamps have been a personal object of fascination for many years.
They are objectively pointless objects, producing little to no usable light, and take literal hours to become operational, especially for larger ones, but once they’re going they’re downright transfixing and hypnotic. And the way they work is stupidly simple but at the same time - surprisingly complicated. And that’s what we’re gonna be talking about today. First, the anatomy of a lava lamp. Inside the base is an incandescent light bulb, often some kind of appliance bulb, and then when you put the globe on the base you end up with what amounts to a weird bottle on top of a light bulb. And that light bulb has to be incandescent because these things work thanks to the heat they generate, so it’s a good thing they use appliance bulbs since they’re unlikely to be phased out. Can’t exactly put an LED bulb in an oven, can you?
But as is the case for many things in life, it’s what’s inside that counts. Clearly there are two substances inside this bottle: a clear one, and a not-clear one. Clearly they don’t want to mix, and it’s also clear that the not-clear one is some sort of wax, clearly. When the lamp is cold, it forms a big ‘oil clump at the bottom and some gentle inverting and shaking reveals that, clearly, this is a solid. That much is clear. Indeed, anyone who’s ever owned a lava lamp and watched it warm up knows just how clear it is that we’re dealing with a wax. Except of course those who are both too impatient and too careless to read the labels plastered on the things that say to be patient and then leave product reviews claiming it doesn’t work - those people are lots of fun.
Anyway, a fun, frequent phenomenon found in flava flamps when they warm up is the Spiky Tower of Wax. You’ll often find that the clump of wax at the bottom sort of pushes itself upward as the wax nearest to the bulb melts and expands, and once enough has melted it pokes a hole in the top of the dome, and then splooshes outward and upward where it solidifies once in contact with the still-cold mysterious clear liquid. Then it’ll look like that for another half-hour at least, so be patient, Greg.
You don’t always get the Spiky Tower of Wax, sometimes you just get the Bloaty Glob of Indigestion, or the Fantastic Flippy Flip. No matter how the wax behaves in the beginning, it takes until the entire globe has warmed to the point that all the wax has melted (and can stay melted), and then you get variously colored jiggle’s. What a callback!
Now here’s where our friend physics makes for some magnificent magma magic. The wax, much like most substances out there, expands when it melts. Water does the opposite because it’s cheeky, but anyway once the wax melts its density is almost exactly that of the mysterious clear liquid.
That means it’s not exactly gonna float, nor is it gonna sink. It’ll just be suspended somewhat. But luckily for us, its density - and thus its buoyancy in the mysterious clear liquid - varies a tiny bit with its temperature. And also luckily for us, because the heat source is at the very bottom, we get a temperature gradient across the globe’s length with the hottest parts being at the bottom, and the coolest parts being at the top (farthest from the lamp). So, we end up with this cyclic behavior where the wax starts at the bottom, gets heated by the lamp, becomes ever-so-slightly buoyant in the mysterious clear liquid thanks to thermal expansion, and then it floats to the top. Once there, it cools a bit since it’s far from the light bulb, which causes it to contract ever-so-slightly, and thus it is no longer buoyant but in fact sinkyant, and then it sinks back to the bottom.
If you’ve watched a lava lamp for any period of time you’ll know that these globs of wax don’t really want to combine with one another. Collisions are frequent but more often than not result in a bounce and not a smooth. But there needs to be something to force them back together otherwise at some point you’ll just end up with a bunch of teeny tiny beads floating around as they continue to break apart. So, at the bottom of the globe is a coil of wire which serves to break the surface tension of these globs and force them into one big glob again. Thus the lamp can operate continuously. This also keeps the wax in contact with the hottest part of the glass at the bottom, making it heat faster and keeping things moving.
Now, you might be wondering what this heretofore mysterious clear liquid is.
Or for that matter, the wax. Ordinary candles are made of our ‘oil friend paraffin wax, which melts at fairly low temperatures and so seems like would be a good candidate. But paraffin wax is much less dense than water and would never sink in it, so if it is paraffin wax, the mysterious clear liquid would have to be something else. Now there are clear liquids out there in which paraffin would sink,but many of them are flammable and thus pose a problem. A large quantity of, for example, acetone in a glass bottle above a light bulb would probably not get UL approval. Plus, many of these potentially OK liquids would mix with the paraffin and we can’t have that. We need it to be separate like oil and water.
So, as it turns out, that mysterious clear liquid is in fact water. Which now makes the wax a mysterious translucent substance. For what wax behaves like paraffin but also sinks in water?
The answer is: paraffin. OK, so now comes the part of this video where I make my very own lava lamp fluids for my very own lava lamp. I've done this once before, and here is the beautiful result. Yes, the base is… a bucket and the globe is… a wine bottle but this is actually functioning like a real lava lamp.
You can look online for home-made lava lamp recipes but most of them are, well, terrible. I mean, sure, they’re kid-friendly and most are designed for fun little science projects but vegetable oil in water isn’t at all like the real thing. Eventually I found a recipe that is probably exactly what’s in commercial lava lamps.
Or at least, what once was - this recipe uses nothing but what can be found in a craft store and a Walmart, but one of the ingredients isn’t available for sale in all fifty states any longer....
And I’ll explain that recipe shortly but first we need to swap out this cheap IKEA table that I care for at least a little bit with a folding table that I care for almost not-at-all. ‘Cause you know, messy. Did that cut work?
I hope so. Doesn’t matter because this part didn’t really go as planned exactly. I am one for three here, and I’m fairly confident I’ve figured out why. But first, for those of you looking at this lamp with its clear liquid and yellow wax and wondering where one can find such an uncommon color combination,
well you can’t!
That’s because this lamp’s goop has been replaced with my very own, and as you can see it’s working quite well. There are some things I’d like to improve about it but let me now explain how this was done. The wax is in fact ordinary paraffin wax. I’ve used raw paraffin from a craft store rather than just melted some white unscented candles down, which I’ve done because a previous lava lamp attempt with simple candles clouded the water. However, I’ve discovered that perhaps the wax wasn’t the issue there - more on that later. The water is ordinary distilled water (tap water would probably be fine, too, for what it’s worth), and a dash of dish soap, and kosher salt. Let’s start with coloring the wax.
What has proven to be the most difficult to recreate aspect of commercial lava lamps is the color. Paraffin, when it melts, is transparent but that would be kind a hard to see in a lava lamp. It might look cool if dyed with candle-making dye, but I’m looking to recreate the translucent look of a real lamp. I found with this one successful wine bottle lamp that adding a bit of raw titanium dioxide powder seemed to work a treat to make it cloudy, but I added a bit too much and the consistency is kind a… not great. This time I tried simple oil paints. I really just want the pigments inside of the paint, but the linseed oil base should hopefully dissolve into the paraffin well-enough. I experimented with blue, yellow, and brown and was quite happy with the result.
In the end it still wasn’t quite perfect, after some time the paint does settle out towards the bottom of the wax, but with enough movement it gets mixed up at least a bit. I’d like to get my hands on some raw pigments like the titanium dioxide powder in here, and I may give powder paint a shot in the future. So long as it can dissolve into or be suspended in the wax and not leech into the water, it’ll work. Well mostly, we’ll get to that. But anyway...
So now that I had a reasonable method of coloring the wax, it’s time to discuss how you get the wax to sink. This part is where I think some mishaps occurred this time. We need to increase the density of the paraffin so that when it’s melted, it has a specific gravity of about 1 - that of water. So we need some sort of oil-soluble chemical that is very dense. And it turns out that a somewhat commonly-available automotive chemical fits the bill. What is it?
Ah, so here’s where I get a little disclaimery. This chemical is, to put it mildly, questionable. It’s probably not particularly dangerous to be around, after all automotive technicians have for decades sprayed this stuff haphazardly all over brake parts and whatnot, but it is recognized to be a probable carcinogen with prolonged exposure, and there are also a lot of other anecdotal health effects associated with this chemical’s use, I wouldn’t consider this entirely harmless. Plus, I am not going to be using it for its intended purpose whatsoever so, with that in mind; This video is intended for entertainment purposes only and does not endorse the use of this or any other chemical product in a manner inconsistent with its labeling. Do not try this at home. And, aside from potential health and safety risks, this chemical also has certain environmental risks, too!
Fun fact, this was widely used in dry cleaning, and I believe is still pretty common in the industry today!
Dry cleaning doesn’t mean things don’t get wet, it just means they don’t get wet with water. In the dry cleaning industry this is often called perch, short for perchloroethylene. And the reason why it’s environmentally problematic is the precise reason it is useful in lava lamps - it’s very dense. The specific gravity of this chemical (I’m not gonna keep saying tetrachloroethylene, OK?) is 1.62, meaning that that is 1.62 times denser than water. Great for my needs, but a problem for soil and groundwater contamination because this stuff just sinks. And stinks, for that matter. This is probably the reason it’s been outlawed in some states. Newer formulations are various concoctions of other fun things. Now, to be clear, this environmental hazard is generally only problematic for big industrial spills. This stuff evaporates quite quickly, which is why in some states anyway we’re still selling it in spray cans like this, but I’m just giving you yet another reason to consider this something that ought not to be played with. But it is exactly the sort of chemical we need to make paraffin denser. So here’s what I did. First, I consumed the contents of and then cleaned out a couple of wine bottles to hopefully make into fashionable bucket lamps.
Now, I found that the punt of the bottle - that’s the protrusion upward into the body by the glass - should be minimal to nonexistent for best results, and we need to add some sort of coil to help the wax reform at and stick to the bottom, just like in a commercial lamp. It doesn’t seem like it needs to be rust-proof as once it’s covered in wax it will pretty much always be covered in wax, so I used a couple of random springs. I learned from this previous wine bottle lamp that you want the coil to be a bit smaller than the diameter of the bottle, as otherwise the wax can form a giant ball that never touches it given enough time. After I was satisfied with the coil, I added distilled water to the bottle and placed it on the base. I wanted it to be close to operating temp for when I added the wax. As it was heating, I prepared the color of wax that I wanted in a glass jar using a double-boiler.
After emptying the contents of a can of brakleen into a mason jar outside, I then added it to the wax - something like one third the volume of the wax seemed to work OK, but I was totally guessing everything here. Once it was mixed, and assuming the water in the bottle was hot, I dumped it into the bottle. Here the wax didn’t sink so there wasn’t enough brakleen in it. I experimented with using syringes to inject the brakleen into the wax, and this worked sort of OK but was quite slow and ended up in the thing I was hoping to avoid:
little balls of way too dense wax rapidly sinking to the bottom. In the end I used a larger syringe without a needle to simply shoot into the top of the bottle. Once the bulk of the wax had sunk, it was on to the finessing. If the wax is too dense, this isn’t a problem - we can easily make the water denser by adding salt to it, and in this case it’s best to use kosher salt which won’t cloud the water. I found that it was best to make a very saline solution and use a syringe to add it to the water. Then I simply added the brine to the bottle until the wax started to float. Some fine-tuning was of course necessary, and luckily if you add too much brine we’ll all you need to do is remove some of the liquid and replace it with plain water.
This process is a bit finicky though, as you can’t start with a full bottle unless you want to deal with overflowing, and I still had to remove some liquid anyway which means you’re screwing with the ratio of salt to water once you add either brine or plain water... so... But in the end it wasn’t much of a hassle and I found the process worked a treat. The idea of making the brine solution really made this a fairly straightforward affair, but here’s where I ran into problems.
The water was starting to cloud and I couldn’t figure out why. It didn’t seem like it was the paint - the earlier test didn’t have any issue with clouding. And simply adding the salt alone shouldn’t have clouded the water. What’s more, the wax seemed to be separating somehow, as if there were impurities in it. I didn’t know what to make of this behavior until I happened to notice that the can of brakleen I had used for this wasn’t purely tetrachloroethylene. It also contained petroleum distillate and trichloroethylene. Now, I’ve had these cans for ages - I bought them something like a decade ago when I first tried this - and I never noticed that this one was different. I suspect that the other components were reacting to the paraffin wax which caused both the clouding of the water and weird impurities. And perhaps this was the culprit of my earlier failed wine-bottle lamp with cheap candle wax - perhaps the wax was never the issue.
Regardless, I’m considering the blue and brown bottles to be lost causes. It seemed as though the wax impurities could be removed with some finagling - a sort of crust was appearing on the surface of the molten wax and it could be removed with a pokey thing - but a couple of attempts at this were fruitless for the brown bottle. However, the yellow actual lava lamp, despite initially having the same clouding and impurity issues was spared somehow. After removing the crusty wax, it came back together with little clouding. I simply repeated that again, removing whatever tainted wax I could, and changed the water, and now its remained almost perfectly clear. So that’s neat. The yellow lava lamp went a little differently, of course. It started life as a brand-new pink wax with purple liquid lamp, a color combo I’ve never really cared for despite being on sale forever, and after being warmed up just one time I unceremoniously opened the bottle cap and poured its contents out. A quick sniff test revealed that, for sure, commercial lava lamps are no longer using tetrachloroethylene in their wax.
It smells almost like plasticky flour, or something like play-dough, nothing like the sweet chemical smell of this stuff. I’m very curious about what this wax is, and it’s undoubtedly safer than this concoction I’m cooking up. I cleaned its coil simply by running some boiling water over it, and washed out the bottle as best as I could. From there the process was the same, but this time I added too much brakleen and the wax immediately sank. I actually would prefer this to needing to add it to floating wax, but you do need to be careful because if you go overboard on the brakleen no amount of salt will get the wax to float. Luckily, though, not much was needed to get the lava flowing.
The last thing needed to make a decent lava lamp is a couple of drops of dish soap. This helps keep the wax from getting stuck to the glass, but more importantly it makes the lamp more visually appealing. Without it, the surface tension of the water tends to keep the wax as just a couple of big blobs. The soap reduces that surface tension and so you get a more active lamp. In hindsight, it seems best to add the soap to the water before you even add the wax, however I began to suspect the soap may have been causing the clouding problems. It sort a way, but only because of the wax impurities caused by the non-pure brakleen. It seems like the soap was helping to get them out of the wax, which is I guess a good thing, but led to clouding. Now, this recipe is far from perfect. For one, it requires and absolutely perfectly sealed bottle.
You can still smell the brakleen when it’s added to the wax which means it’s slowly seeping out of it and evaporating. With the wax underwater this doesn’t matter - it’s not water soluble so it probably just stays in the wax, but even if it leached out into the water it would immediately sink to the bottom where wax would recombine with it again. However, if left open to air, enough of it will leave the wax over time to screw up the density. Ask me how I know. Also, well, the oil paint seemed promising but in the end... wasn’t great.
It seems like the linseed oil base isn’t actually dissolving into the paraffin. It looked like it was, and perhaps it’s the bad brakleen that’s messing this up, but over time the paint is sinking in the wax and not remaining suspended. Making things worse, the coil in this commercial lamp seems to be acting something like a strainer, so over time the wax becomes clearer and clearer. I can get the paint to recombine by sort of twisting the globe while it’s warm and the wax is settled at the bottom, but this is annoying and also - the paint just isn’t combining well anymore and it’s all flecky and gross. I may try oil paints once more with the correct brakleen, but I’m willing to accept that it just doesn’t work. Now, the most remarkable thing about this process is how finely balanced it is.
The difference between no movement and good movement was about 10cc of my brine solution, which itself had perhaps a gram of salt in it, if that. The overall change in specific gravity on the bottle was miniscule, but that’s just the world of lava lamps. They are finely tuned… bottles. Speaking of, some tips and tricks!
Some lava lamps misbehave. This one here just loves to get bubbles in its wax. One thing you can try to help mitigate this is to lower the wattage of the bulb - Tech Tangents had success with this for a pesky lamp. He also noted that airflow around the lamp can affect its performance, which actually makes perfect sense given how fragile this buoyancy balance is. Tiny changes in temperature can make the wax sink or rise, and speeding up the rate at which energy leaves the bottle will greatly affect its behavior. If you want even finer control, you can put your lava lamp on an inline dimmer switch. I’ve personally only found these necessary for the giant Lava Grande lamps - and eventually they added dimmers to the lamp bases themselves. I’m not even sure if they still sell those, though They really need something like 85 watts of output, which isn’t exactly a normal bulb size. But, easy enough to make happen with a dimmer!
And before I go, I’d like to talk about how I’m going to deal with this environmentally problematic goop I’ve created. It’s probably not the best idea to just send this to landfill, so I’ll be keeping it. I’m gonna melt all this failed wax down into a clump and keep it open in the garage because I suspect if exposed to air, eventually all of the brakleen will evaporate out of the wax. The old mason jars I was using way back when for this no longer have any odor to them, and the remaining wax has become harder with time (the wax and brakleen combo is quite soft as a solid - and what’s left now feels like ordinary paraffin).
So it seems like eventually it just evaporates, despite being dissolved in solid wax. I’ll be curious to see how long it takes for the wax to off-gas, if it does. But if that fails, there’s also option B. The boiling point of tetrachloroethylene is 250 degrees Fahrenheit, or 121 Celsius. That’s much lower than the flash point of paraffin, so I could also just put this in a toaster oven set to 300 degrees and… wait a while. Probably best to put the toaster oven outside if I’m gonna do that. But this should cause it to vaporize and enter the atmosphere where it will decay into less harmful stuff. Its lifetime in the atmosphere is estimated to only be 2 to 5 months, so I’m not terribly worried about the impact of this, though I do want to be careful. Anyway, thanks for watching. I hope you enjoyed this video about lava lamps and one way they were made.
I actually have no idea if this recipe was ever used in commercial production, and there’s no way I’m gonna remember where I came across it exactly, but if memory serves it did seem like it was, “ahem” borrowed from someone back in the day. If there are any chemistry-inclined folks out there who know of a more inert way to do this, or perhaps might have a guess at what’s in lamps today, please do leave a comment.
I’d also love suggestions on how better to color the wax. What I’m leaning more towards is actual candle-making dye for color, and just a bit of the titanium dioxide powder that in here to achieve translucency. Though, as I said, I want to try powder paint and track down some raw pigments, too. I think the biggest issue with the oil paint is that the linseed oil isn’t actually dissolving into the paraffin, and it appears much denser than the wax. Since the titanium dioxide power seemed to do so well for this one, I imagine any fine powder that can remain suspended in the wax will work. I’ll report back if there are any significant findings. Toddles!
Literal hours to become operational especially for lawl...appliance bulb, and then when you put the…I did that too soon! This is so exciting!
OK, so now comes… eh no I need to.. Cuz its gobedy go do I know what I’m doing!
I know what I’m doing. I should probably mention that there is an alternate method to this that I want to try, that’s one of the reasons why I’m doing three total lamps, or I hope to anyway.
