DIY Electric Furnace: Part 1

In this video, I make an electric furnace that is capable of melting copper. I construct and run an initial test of the furnace to determine its flaws, which I will correct in part 2.
Patreon Link: / dougslab

[@jasonpatterson8091]

Next purchase, proper tongs and gloves. Awesome video. :-)

[@Impatient_Ape]

Nice! And definitely not as stinky or hazardous as an arc furnace. BTW, running the heating element 110 VAC instead of 220 VAC means a thermal power output of 1250 watts and not 2500 watts. The resistance is relatively constant, so the formula to use for power in this case should be Power = V*V / R.

[@theLuigiFan0007Productions]

Voltage is actually around 121.25V-126.75V wherever I'v checked it in our house (~5% tolerance). Most appliances are rated 115VAC, but the real voltage is generally 125V/250V. There's a pretty big tolerance in the allowed voltages between providers and electrical systems. Single phase: =>106V, =212V and =

[@downtroddendave860]

+theLuigiFan0007 True, but the point is the same... when Joule heating like this, halving the rms voltage reduces the mean power output to 25%, it's just due to the output being directly related to the square of the input voltage. Of course assuming that the temp coefficient of resistance of the wire is not just linear, but flat across the temp range it will be used at. As far as the 110 vs 115 v 125VAC... household power (as shown in the video and as you observed) should be thought of as 120VAC nominal plus or minus 5%. The 115VAC you mention appliances being rated for, that's just the nameplate value and they should be able to handle plus or minues 10% of that value without real worry. The 126.75VAC(rms) that you measured is on the very high side but nothing I would be calling out an electrician for. I might even suggest that the higher readings are from locations with less feet of copper between the outlet and the distribution board/breaker box.

[@theLuigiFan0007Productions]

JimmyDB - Had forgotten to take into account the exponential power draw with voltage increases for the same resistance. Thanks for the tip. 10% tolerance is a great thing indeed, unlike the regulators I build for digital electronics (CPUs, Video chips, etc). 0.5% or less tolerance. Except Atmel chips like the ATmega 238P (1.8-5.5VDC)... they're pretty robust. Funny thing is about my voltage, the outlets in my room are the exact diagonal opposite side of the house as the breaker panel, and all the outlets are within about 5% on the readings. I guess the ancient wiring isn't so bad after all. Besides being ungrounded, of course :D. I'v gotten a bit of a prickle off power supplies that need to be ground referenced for safety reasons and had to use adaptors for. More accurately it was like _"huh, this feels odd... _*_touches harder_*_ AH F***.... Note to self: neon sign transformers must be grounded"_. XD I'v noticed on days the voltage is a hint on the high side there's significantly less load (less harsh temps, a line gets switched off somewhere for maintenance, etc) or it's usually during the late night or early morning. I guess they don't compensate for small grid sections in real time.

[@downtroddendave860]

+theLuigiFan0007 Been there and done that with faulty/missing grounds... lol, it can wake you up faster than coffee... or knock you out even quicker... luckily, I have only been knocked out once when 'becoming one with the circuit' but have come in contact with a number of boxes that try to tickle you when touched. Interesting about the small grid, each type of power plant design has different ways of dealing with grid loads and at home we see maybe 5 good drops or spikes in the line per day (according to UPS logs). Our electric company keeps swapping out and adding transformers in this area as well as some jerk around here [looks around] seems to keep doing something to cause them to spill their oil.

[@theLuigiFan0007Productions]

JimmyDB - Must be the squirrels trying to steal copper again. They never learn because it's always too late.....

[@ClagwellsGarage]

I need a quick fab solution for a 900deg C lab oven and this worked out well. Thanks for posting.

[@j_sum1]

Nice work, Doug. Firebricks are on my to-get list although I was thinking of a charcoal fired furnace for my use. Good to see it in operation. Happy calcining. :)

[@nedshead5906]

+j_sum1 j_sum1 I tried to find some alumina silicate fire bricks once, the closest I could find was pizza oven bricks. if you happen to come across some let me know

[@nedshead5906]

+Energy Unleashed yeah, I used the pizza oven bricks for an arc furnace and produced some calcium carbide, they did the job but they didn't hold up very long and eventually cracked and fell apart

[@DougsLab]

+Energy Unleashed I should have used a push rod but I figured if I took it in short bursts I could just poke it in there with my hand. Plus, the video was kind of funny. I will be making stuff like calcium oxide, calcium carbide, and phosphorus. I will probably also use it for small aluminum castings, and preparing silver shot.

[@LaserJake99]

by the way, if you want to freak people out, put li600 space shuttle insulation tile in below its melt point (it will shrivel up if too hot) pull it out while glowing hot. wave it in air for one or two seconds and as long as you don't squeeze it you can hold it in your hand. it will be glowing yellow hot. awesome party trick.

[@dimitar4y]

HEYY THATS COOL

[@custos3249]

PhD holding chemist: **puts hand in running furnace** ow **puts hand in again** ow **and again** ow

[@connormcneill9024]

He needed a proper sample size to determine statistical significance.

[@chewy2420]

lol watching you try to put that crucible into the furnace is funny. I work with a 1050*f furnace everyday :)

[@guitfiddle]

This is an awesome DIY. I would upgrade with PID style temp controller, but great proof of concept. Thank you Sir.

[@owensnyder8616]

if you dont mind me asking, would a PID temp controller be able to connect to the heating element and control the temperature? or would it only tell the temperature, from which you would adjust a seperate device.

[@ETllc]

Thank you very much Doug . Could you provide link to heating element that you bought on ebay?

[@Inesophet]

i made the same design with one exception. I drilled into the brick for the channels so the khantal doesnt spring out at one point. Also you REALLY want to have all the safety gear, tongs and everything you need before turning the thing on. If you build a more horizontal furnace you can insert gradients and baffles. Very useful if you are into synthetic crystals. By far the most cost effective method to create large Nd:Yag crystals.

[@djdrack4681]

I have a project I'll be starting soon on trying to convert a bread machine into a DIY heater-stirrer. I'd love to see a DIY mantle though.

[@scottyg4605]

The seen from Jaws came to mind...."I think we're gonna need a bigger boat" 💥🔥🔥 And maybe some glasses to save melting your Cornea's off 😎

[@seymourpro6097]

To make the wire lead outs you straighten the coil out and double the wire over and twist them separately tightly. This causes both parts of the twist to carry current so make less heat there and more heat in the furnace. Also terminal blocks with metal parts made of nickel and a ceramic body.

[@dpasek1]

The way to make electrical connections to the ends of the heating element is to spot weld the heating element wire to a thicker straight piece of Kanthal wire, like 2 or 3 thicknesses of the original wire, and run the thick wire through the back of the furnace. Thicker wire will not dissipate as much heat per unit length and will run at a lower temperature which will prevent burn out. You could also use long stainless steel bolts, but that is not as reliable for high temp operation. SS hardware works fine at lower operating temperatures. Also, get a type K thermocouple temperature controller. They are cheap and safer than running open loop on the temp control.

[@bradforddrake8633]

Would it be possible to build a larger oven with the same depth and height,but 2 bricks wide? I have been unable to find firebricks longer than 9 inches.You could cut off the outside of 2 of the angle irons on one side and hold up the bricks with stainless steel wire underneath the bottom of the ceiling bricks, attached to the angle iron.Please give me your ideas in this larger furnace.

[@MostFolkCallMeOrangeJoe]

You should get a fixed shade welding lens (shade 5 would probably do) to put over the camera so we can see in there better. I'm not sure how well you can see it in person but O/A goggles will help if you're struggling to see. Get a pair of cheap MMA gloves too, they won't catch fire like yours did. Very nice furnace BTW.

[@MichaelLangell]

Nice furnace it’s a nice simple design and anyone could build it... nice bong bowls they look clean

[@bradforddrake8633]

Fabulous!You could drill a small hole thru one of the ceiling bricks for a thermocouple which measures temperature!

[@peterciurea7771]

straighten some of the coil on the ends and twist it double. The drop in resistance will prevent that section from getting red hot, and save your connection

[@ocng]

Just a note on power versus voltage: half the voltage also means half the current. So its only a quarter of the power. This is especially important when dealing with double the voltage (four times the power...). Thought you might wanna know.

[@skinnwalk3r586]

and never a part 2 of this :( i'm sad

[@asciisynth]

Amazing. I've been looking for videos to help me build a burnout furnace and possibly something to melt silver, and you made the whole build process look easy. You should buy some leather gauntlets before you use it again, though ;)

[@CoolKoon]

Wow, you were very brave to put your hands near in gloves made from some synthetic fiber :P GENUINE leather gloves are the minimum (they'll transfer the heat right to your hands though), but good welding gloves are a must for this kind of work. Oh and awesome job with the furnace ;)

[@DimaProk]

What are welding gloves made out of? I got pair of thick yellow leather gloves from Harbour Point and they are nice but they don't protect from heat very well.

[@CoolKoon]

Also leather, but they're a bit thicker than the conventional leather gloves and are probably also treated with some flame retardant that'll lessen the chance of it catching fire near (or touching) hot objects. They aren't (nearly) completely heat-resistant though, so you should NEVER grab a hot object even with welding gloves on (sure, it'll avoid you getting instant 2nd degree burns from the hot object, but you'll still feel the heat through the gloves). Use metal tongs instead. BTW the welding gloves also come handy from protecting your hands as you move them near yellow to white hot objects. You see they're so hot that even the heat they radiate is more than enough for burning your hands without gloves.

[@picramide]

The way to bring the Kanthal wire out is to uncoil about 8" on each end, double it back on itself, and twist it. Outside the furnace, ordinary steel bolts and straps can be used to make electrical connection to these stubs.

[@NormReitzel]

I uncoiled the elements as you suggest but then put a piece of 1.2mm stainless tubing over them and crimped down on the kanthal. Small hole through insulation and stainless tubing is a modest heat sink.

[@zanpekosak2383]

I recommend side hinges. Swings left to right. If you open it upwards your hand will be burned from the heat that rises.

[@lorentsmuller4207]

What is the type of variac you are using? The specs of it. Edit: I paused the video and googled the model number. 20a 130v variac.

[@relic2279]

You know when you see something on TV that you have or own (the exact model) and you're like, "Hey, I have the same exact thing!" all excitedly? I did that when I saw his dremel and guide. Then I realized that particular Dremel is ridiculously common (Dremel 3000) so I was no longer special. I will say that I've gone through 4 harbor freight rotary tools in as many years despite the fact that i don't use rotary tools all that much (couple times a month at best). I bought my mid-range Dremel just over 3 years ago and not only does it still run like it's brand new, but looks brand new too. Never again will i buy a harbor freight rotary tool... 4 of their rotary tools costs nearly double the price I paid for my pre-owned Dremel I got on eBay.

[@grimwurks]

have a look at how a pottery kiln is constructed, the elements are pinned in place with kanthal wires, the elements are stretched straight going out of the brick . . . keep working at it

[@minipac2]

Holy crap! Whilst I know what you know what you're doing I have to request that you PLEASE trim those copper rods that are used to short the element - it's just a horror story waiting to happen (>⌒

[@theLuigiFan0007Productions]

+Minipac S I was also thinking they looked a bit close together. We don't need no indoor fireworks going on. Or even brushing it with your hand for that matter. Hot and electrified aren't exactly healthy. XD

[@buckstarchaser2376]

He was running it at 100V. That's more of an 'educational experience' than a 'horror story'. I agree that it's silly to keep it like that though.

[@zanpekosak2383]

When is pt 2 coming?

[@skyhawk551]

that diffidently got hot enough to do a lot of synthesis reactions, the videos with this should prove interesting

[@PriesterJohn1123]

Where is part 2? This first part was published over a year ago.

[@The_3_Triangle]

nice video...if you want to control the temperature use PID controller

[@hellhasgone01]

Dude holy crap this is nice. This is just what I was looking for!:D Haha this is amazing. And nice job with achieving that temperature. I'm wondering on the small things like exactly what that thing is supplying the voltage. Exactly how to use and how it works with placing the coppers rods in the coils to reduce heating. And just small things like that to reduce that temperature around the holes and how exactly you did this.:l wow nice. Can I have a little grocery list and specifications to build this? I'll tip and I'm gonna participate in the next donation of the next experiment lol.

[@Journeyman1642]

No high temp cement between the bricks??

[@custardo]

Next patreon goal: an asbestos suit ;)

[@grantstewart5453]

If I were to put the heating element into a fire brick say an inch deep in a circular stove top pattern to make a hot plate would there be any risk of the element arching to a metal pan sitting on top of it used as a sand bath for dry distillation?

[@tommmiseuf.7897]

hey! how is your project going? do you have any updates? Is it still working for you? Can you reccomend any upgrades to reach even higher temps?

[@KowboyUSA]

May try flux and/or a crucible with a lid.

[@Cylindricity]

Is your outlet 10A and 120V?

[@tim9lives]

Cool video. FWIW..... Longer Needle nose pliers and leather welding gloves would be my choice. Anyway...... Very good build. I like its simplicity.

[@FoodieSanjana]

hey.. its really easy to make... can you do a video for making an oven.. easy oven which. we can make at home.. using a heating plate and a power supply..

[@LucS0042]

Can you add a thermocouple wire lead?

[@DougsLab]

+Luc Serre I ordered one from China on eBay about 2 weeks ago... it's on the way!

[@StephenBecker]

+Doug's Lab Would be nice to put a PID temperature controller on it too.

[@lorentsmuller4207]

@@DougsLab did you burn down your lab with this kiln?

[@ExemplaryLigas]

some borax may helps you, where do you get your resistence? kind regards

[@Cristi0986]

where is part 2?

[@bartholomewsimpson4621]

A pyrometer is always a help, "old school" analog meter units are still around. Bulk, type K asbestos covered thermocouple wire is still around also. One should "torch fuse" the raw twisted end of the thermocouple wire into a small bead, ..the wire "will" work by simply twisting the tip/sense end tightly, but it tends to be unreliable, esp. at high temps. They do have digital PID thermal controllers with K wire on eBay,.. if one wants to go high tech. Also, they use carbon granules (cheap stuff) contained in buckets for small kiln melting of copper/brass. The carbon absorbs the oxygen so the metal doesn't oxidize. Look up PMC carbon firing.

[@dedosare]

Great job! I love your videos, Keep up the good work!

[@mightywhite360]

You need some nomex gloves or something. those work gloves dont stop heat at all. even leather welding gloves wont stop that kind of heat. I use welding gloves when Im using my propane forge/foundry, and they instantly start smoking when they get too close and the heat just goes right through them. I have some really heavy duty foundry gloves that I got at a farrier supply shop. They stop all the heat pretty much but they are mitts so no finger dexterity what so ever.

[@jamesstrong1270]

Ever consider making a nickel/aluminum alloy? Maybe digesting the alloy in a hydroxide solution to obtain Raney Nickel.

[@Ammondn]

they make heat resistant gloves for welders, you might want to get a pair. ;)

[@stephenjacks8196]

I worked at a lab where someone set the temp too hot and melted Platinum crucibles.

[@lorentsmuller4207]

Were you able to get the temperature to hold at 1200c?

[@danvandertorre9280]

if you gently rub them together they will fit together better and knowing your tem is a good thing very good job .

[@rubysante4005]

excellent, you are super talented

[@prmaddock]

im thinking about making a longer one for knife making, would presenting metal into this style of furnace be a bad idea due to arcing and what not?

[@dissahc]

was the furnace hot?

[@rafaeldavidcastroluna7600]

Hey Doug, what about an arc furnace made with carbon rods from batteries? you can easily melt copper, zinc and a lot of metals.

[@mrraimundo130]

Excellent work. I have one question you may can answer, how can you achieve 1500 C°?

[@botanikera4806]

is that nichrome wire? that heating element your calling, is that nichrome? what amperage are u using at those 90 volts?

[@wiktorstankiewicz3568]

Use carbon rods from 4,5v batteries. You can reach tungsten melting point with them, and they wont melt.

[@lkexpress]

It looks like the firebrick where you put the terminals in cracked. Will that be a problem?

[@plasmaguy5]

stretch the elements more to reduce current and heat evenly

[@peteraugust5295]

interesting buil.d Are there heating wires that you can hook up straight to 220/230V?

[@briceviolette8415]

what if you put two large bolt in the back as the terminals

[@rothman78]

You should stretch out the heating elements, right?

[@Speeder84XL]

Yeah. Then it was not very good to put the copper strips inside the spiral the way he did (he shud simply have carved out some more space in the brick). It kept the spiral from overheating, but the copper do melt on the inside (just like it did in the crucible) and make contact with the element. That might destroy the wire. The best thing is, to put the spirals on ceramic tubes so they can radiate free in all directions, but it's hard to do on a furnace this small.

[@cmike20xxx]

How do you control the temperature I want to go down to 308 degrees Celsius how many watts would I have to use get it to 308 degrees Celsius?

[@atul2048]

what is the thermal conductivity of the brick you are using?

[@x9x9x9x9x9]

Where do you buy fire bricks? I have been trying to find some for a while but I guess I am doing something wrong.

[@bluedeath996]

Is there a part 2 to this?

[@kevinbyrne4538]

Maybe you should add a thermocouple to your shopping list, so that you can accurately measure the temperature at which you're operating.

[@IndomitablegamingYT]

Can someone link where to find these heating elements? I searched but i coudlnt find it.

[@wazidabdullah4926]

what if i want to produce 3000 degree celcius? plz tell me the chamber size ,heater watt,voltage,curent, nd power i need to use.

[@srnkp]

Idea is very good but you didn't show the melted metal drawback

[@nilnull5457]

long time no see. Can you tell why did you stop uploading?

[@Oldman-Havok]

Could you please post links to where we can purchase these items?

[@MEDDERX314]

If you buy some firefighting gloves they will smoke but not catch fire. If that is too much money though doubling up on some cowhide work gloves from a hardware store should work alright also

[@ted_van_loon]

hi can someone give for a good and not to expensive nichrome wire prewided for heating and a variac which can hold the wattage.

[@Inesophet]

Dude, you can literally do this by hand. its like 2 USD and takes 5 mins.

[@ted_van_loon]

​@@Inesophet Well the variac is the main problem the heating wire I managed to find easly yet all Variacs i seem to find are quite weak and expensive.

[@Inesophet]

@@ted_van_loon Variac is not really important. Just use maths to calculate how long your coil should be. Stay 25% under what your home wiring is rated for and you should not have a problem. Heatcontrol is best handled with PIDs and not a variac since input current and final temperature do not correspond well together. Thats also much cheaper. A PID with a good heatprobe costs around 30USD while a good variac that can drive a freaking furnace will be 10x that.

[@benpuig1593]

where do you get fire brick?

[@bpark10001]

Please ground the metal frame of the furnace so you don't get fried! Since the elements are exposed inside the furnace, you should also put interlock on the door to cut off the power when the door is opened.

[@Artoconnell]

do we need to take up a collection to get you some gloves and pliers?

[@FrostoLP]

Nice Video man! Can you tell me, what kind of Cable this was?

[@alexi3489]

It's nichrome wire. Available off eBay or Amazon.

[@alexi3489]

It's nichrome wire. Available off eBay or Amazon.

[@alexi3489]

It's nichrome wire. Available off eBay or Amazon.

[@alexi3489]

Sorry about that, it kept giving me an error, I thought it wasn't going through.

[@alexi3489]

Sorry, it kept giving me an error. I didn't know the comment went through. :/

[@robertotoca1850]

Please tell me what is the heating element and where does one get it.

[@TheItzGambit]

The heating element is resistance wire used for electric stoves, you can find it on ebay

[@jamesmclaughlinprimitivele4587]

stainless steel bolts for the leads

[@bpark10001]

You don't have the wattage correct. Wattage scales as voltage SQUARED, so if it is 5000W at 240V, then it should be 1/4th as much at 120V or 1250W. Both the current and voltage are reduced as the voltage drops. Since power is the product of these, that's where the squared term comes from.

[@aaronskoy957]

Nice! He did all that with a Dremel.

[@davidzed3274]

Do you need to wear special eye protection when looking in the furnace? (UV radiation?)

[@DougsLab]

+David Zed Yes, it is starting to get to temperatures where the light can damage eyesight.

[@RobertSzasz]

Yes and no, IR rather than UV, (cataracts rather than sunburned corneas)

[@mrchangcooler]

As soon as I saw you with your tiny tool trying to get that out I knew immediately it wasn't going to end well for your hands.

[@FreezeDriedGirolles]

Yeah... Perhaps don't wear black, flammable, heat absorbent gloves when fishing stuff out of a 760 degree furnace. But other than that, this is pretty awesome!

[@JoshuaRando]

+Freeze Dried Girolles Yeah. He should sew some gloves from an emergency blanket.

[@nicougrikify]

can someone link me the wire to purchase please

[@joeestes8114]

how long of a element is it?

[@astroglide420]

I didn't understand how the copper in the back reduced the heat on the exposed coils. Can someone explain.

[@zacharykokot6625]

spinNspiral the high conductivity of the copper allowed the heat energy to be transferred through the copper and out into the air. so the outside terminals would stay cool.

[@astroglide420]

Thank you.

[@lorentsmuller4207]

The copper extended the contact of metal on metal to the electrical connection point.

[@LuizHBaroso]

what the name of this red machine that you turn on the outlet? you need one of these to the oven, or gives substituíla for something? electric I do not know much

[@makaukenas]

That red machine is Voltage regulator. It lets you change Voltage so you wouldn't blow up a fuse with that heating wire hooked up directly to the power outlet and it also lets you change the temperature (more Voltage = more heat).

[@LuizHBaroso]

Ernestas Titas Thanks \o

[@THEGREATONE420]

@Ernestas Titas would it be a problem to use a motor speed controller/dimmer to regulate voltage?

[@853nova4]

How many watts of your furnace?

[@sunshines278]

what is the bricks name

[@rijkwiersema]

How do you wire iT up?

[@masondaub9201]

half the voltage would produce a quarter of the power output in a resistive load

[@KowboyUSA]

Outstanding!

[@atrumblood]

Haha, damn. I'd say an upgrade in fire resist is needed for that beast.

[@shoukatbabar739]

Beautiful ❤️

[@RHaney2012]

Thanks for the video. I was wondering if anyone could refer me to a heating element and a controller to set a temperature and have it auto stay at that temp? I want to build a foundry for myself but I know nothing about electronics and such. Could someone recommend me some parts? My plans are to cast fire brick for a rounded foundry and a 10-12 Kg crucible. I'd like to reach temperatures of 2300 F.

[@Cylindricity]

Robert Haney you can buy a kiln for around 400 bucks, probably less used, and those get to 2800.