Ultimate DIY Electric Kiln Guide - The Heating Elements (part 2)

In part 2 we're designing the heating elements to achieve 5000 kW of heating power with some help from Ohm's law and simple math.
Heating element wire: Kanthal type D (1.4mm thickness)
Total power = 5 kW
Number of elements = 2
Element power = 2.5 kW
Voltage = 230 V
Current = 10.87 A (per element)
Resistance = 21.16 Ω
Wire length = 24.1 m
Coil inner diameter = 8 mm
Coil outer diameter = 10.8 mm
Ceramic terminal blocks: www.amazon.com/Ceramics-Termi...

[@SustainableCraig]

This is one of the best, most practical, and well-executed DIY videos I've seen on KZbin. Awesome work!

[@dregenius]

Worth mentioning that north america does in fact have 230V (240 actually, ten more! 😂 ...although sadly we generally don't have three phase in residential service) in every single electrical service installation, commercial, residential, etc., it all has 240V. If you don't want to add a double pole breaker to your panel and wire your own circuit for such a kiln, use the already existing 30A 240V dryer receptacle, or the 50A range receptacle. 😊

[@stevecarswell6329]

I just found your channel today and immediately subscribed. Lots of interesting and diverse content presented in a quality professional manner. I look forward to the next part of this series and your future endeavors. Thanks for your hard work!

[@jakobhalskov]

Thanks Steve, that is so motivating and heartwarming to hear :) Looking forward to see you around!

[@CurtisDavis89]

Same just subscribed after seeing the Part 1 video which was my first video of yours haha

[@glennr9913]

Very well explained and executed. Thanks for taking the time to share it with us.

[@rudajirsek7470]

Many, many thanks. You left me (helped a lot). I have a lathe, but I didn't know how to wind Kanthal wire 1.6mm. I needed 277 threads and then a gap of 3 mm between the threads. It didn't work on the lathe. You showed me the video. Thanks thanks.

[@kalipso1989]

just the information I need.I'm looking forward to your new videos.thank you so much

[@jakobhalskov]

Great to hear Mert, you are very welcome and I look forward to see you around :)

[@ArrisarJ]

excited for the next part, and to try this out!

[@jakobhalskov]

Working on part 3 these days! :)

[@ImUpsetThatYouStoleMyUsername]

Probably the best video i've ever seen.

[@concretecat]

Excited to see it fire up!!

[@jakobhalskov]

Yeah, it gives a nice heat! (Trying to forget the rising energy prices.. )

[@ashleymhills3968]

I have a friend with a 3D printer, would you possibly mind sharing the plans for the part you insert the rod and wire into? It’s a fabulous design and such a well made video!

[@guillermodehollander]

Fascinating…..thank you for sharing. 😊

[@jakobhalskov]

You are very welcome Guillermo :) !

[@davidmarshall7519]

I really like the way you presented the information about this build. I want to make an electric aluminum smelting furnace along the lines you have made. I wanted to make my furnace capable of just pouring the molten aluminum directly into an ingot mold or a casting jig. Ideas? Thanks, Dave.

[@Frank-dg3dw]

Thx for sharing!

[@alaingrenier663]

nice work my friend👍👍

[@adinamarin8955]

OMG!! Thank you for letting this video come into my life!! How much the whole instalation cost you?

[@JBracale128]

Hey man! Your electric oven build was so inspiring i'm trying to build my own for ceramics! I need some help calculating the size and how many coils i'll need. I got a 50l barrel and insulated it with firebrick and ceramic wool leaving me with a inner chamber like a cyllinder of 22cm diameter and 24cm deep. What size wire and how much would i need to get to 1200c with that inner chamber size? Any help would be awesome thanks! Love from Brasil !!

[@dragonfly264]

I was all in ready to get my nephew to help me building this kiln based on Part 1…. until the power design requirements. I’m too scared now 😂. Excellent video though

[@TediChannel23Ja]

Great video

[@eletrogargaltda7200]

Is very Cool my friends !!! Perfect !!!!

[@JulianMakes]

very nice Jakob! i'm looking to make one for bronze. have you melted any bronze yet? cheers and subbed

[@rtufik]

Thanks for sharing. Saudações do Brasil.

[@jakobhalskov]

You are so very welcome! :)

[@amirspb3196]

It was a great tutorial, I subscribed, can you tell me when the next part will be uploaded? I Need To Build It This Week !!

[@jakobhalskov]

Thanks for your kind comment Amir; I will be publishing new videos 2-3 times per month and will be doing other projects than just this kiln, so I cannot promise to have all six planned parts available 'quickly' :) But feel free to write a comment if you got any questions!

[@EpicSpence]

I have a busted muffle furnace. The wire between the 2 elements has snapped. Do you think a nichrome connecting wire is suitable to join elements together when that wire travels outside the refactory lining? It is shielded, but im not sure on the existing wires composition.

[@paradiselost9946]

one thing on the gauge selection... its about surface area, and you can manipulate the size to control the peak temperature, as its just W/cm^2. so, the skinny wire with high resistance will indeed get the hottest, but it also dissipates the least, so it will melt. along with oxidisation etc... short life. cheap though! its quite possible to have a wire so large that the temperature is... minimal. still dissipating all that energy as heat, but that heat ? its not very HOT. irrespective of the insulation, or how long it runs, or anything... you simply wont get over a certain temperature.

[@EpicSpence]

Reading muffle furnace engineer guide for a carbolite system and it mentions current is pulsed at around one third on, two thirds off cycle per second to prevent early nichrome wire disintegration. I think constant voltage will destroy the wire sooner or later. Curious... Is this something you are aware of?

[@simon-ic5fj]

Hey Jakob This is some quality content ive been searching for a while, thanks for sharing!! Im really interested in the electrical part of how you did the wiring for the bi phase plug (in my case i want to wire it tri phase).. did you plug the plug cable strait into the terminal where it meets with the elements or is there something else? Thanks again, i really enjoyed your video!

[@jakobhalskov]

Hi Simon, thanks for your kind comment! The electrical wiring will be the next (part 4) of the series. Until then I can tell that each of the elements is connected between the live of one phase and Neutral. One SSR (solid state relay) is used between the element and live to control the duty cycle with a control signal from an Auber PID controller. Best wishes!

[@simon-ic5fj]

@@jakobhalskov man thats awesome! Im so looking forward to the coming video! It will be great help for making my kiln! Thanks a lot!

[@rozbroz]

This is great! One part I'm missing is the circuitry that would be used from the elements into a Skutt digital controller for 230or 240V?

[@_jow]

i believe the heating elements connect to a relay which is then controlled by a digital controller.

[@jmikronis7376]

@@_jow, actual microcontrollers output in micro amperes so any output has to go through some “chip” that can convert this output signal to one usable by actual driver relay. I’m certain there are “modules” designed for computer interface to power controlling technology.

[@taylorphillips5118]

Will the elements ever need replacing? I was thinking of permanently embedding them in the brick

[@brandocommando36]

couldnt you just take a few cook range 240v heater elements and save yourself all the calculations and cost , these can be found anywhere , thx for sharing ! nice job !!

[@anissbenthami]

Can you tell us why is a thin wire gauge not recommended?

[@happytohelpu2]

Super

[@kawaiiluvlis5805]

Do you know what cause the kiln to power fail?

[@MrJakeDenmark]

Hej Jakob, Har du lavet en styring til din fine ovn? Vh Jake

[@matthewfeatherstone401]

Did you write up the Design Requirements in LaTeX solely for this video? Respect.

[@user-be4yc2vr5c]

Hey bud I'm really struggling to figure this out. I'm trying to make my own home made fiberglass jacketed heat tape. I need it 8' long(a lil longer is ok) And was planning on doing kanthal wrapped around a 8mm rod to coil(8' coil to be stuffed into 1/2" fiberglass jackets) I'm on 120v AC but have a plethra of DC voltage supplies too, including a 24v 14amp and better or smaller. About what gauge and how much kanthal wire am I gonna need?

[@jmikronis7376]

There are jacketed heating tapes made by industry but not with Kanthal wire. The Kanthal wire will break. It is best contained in refractory brick, which is what it was designed for. Essentially, not moving.

[@rusticagenerica]

Great video. Which material is best for 2000°C temperatures?

[@jakobhalskov]

Thanks! I do not have experience working with such high temperatures, so I cannot share any advise on this :)

[@jmikronis7376]

That wold be Kanthal wire. It’s designed for use in kiln operations as in heating elements. It comes in several grades.

[@slicktires2011]

When you divide your heating element in 2 parallel coils, each coil is twice the mass, but runs only half the current, does that mean that they reach a lower temperature? Compared to a single coil of half the size (one quarter the mass of metal)?

[@asdqwe4468]

No, it's not a lower temperature. The manufacturer of the wire usually gives you a power rating per meter of wire. So depending on your total power that can mean you need to use a thicker wire and thus make it longer. Also they will give you numbers on how much the resistance increases with temperature. Most wires have PTC which means their resistance rises with temperature.

[@adamsisson5458]

Maybe someone can help me here. Why cant a 110v 13a circuit power a larger kiln? I understand the obvious that more power is needed to heat a larger area, and that the resistance of the wire chosen is so all of the power will be converted to heat, but you could use a longer and thicker wire with the same resistance spanning more surface area in a larger kiln. Would the rate of heat loss through the firebricks exceed the ability of the coil to heat and prevent the kiln from reaching optimum temperature? Also great video thanks.

[@weeveferrelaine6973]

Depends what temperature you're trying to reach, and what the losses are through your fire brick. Technically a 10 watt heat source could heat a whole room, if it were perfectly insulated. If you want your tradeoff to be that you need to insulate better, then that's acceptable. So is just waiting longer for it to heat up. For most things you would use a kiln for, 1,500 watts like you said should be enough. Generally try to size your coil to whatever power source you have available, just to heat up faster, and waste less time and energy.

[@user-sv6so2fi9x]

مرحبا هل يمكن صهر الالمنيوم بي فرن مصنوع من شريط المدفأة الكهربائية وما النوع المناسب وشكرا بالمناسبة ارجو منك قياس اعلى درجة حرارة وصل اليها الفرن شكرا على مجهودك

[@jmikronis7376]

I did do some research on “smelting” aluminum cans (soda cans). A big takeaway I learned throughout the process - you’ve got to keep oxygen away from it, if not, it all gets oxidized and goes to dust. Make or buy a crucible to melt it in. It gets very very hot so personal protective clothing designed for industrial melting of metals should be worn at all times. Don’t try to do this smelting by yourself, it is very dangerous work. Don’t do this indoors, it’s too much heat and so much can go wrong very quickly. Use the tools designed to work with the crucible that have long handles, it’s very hot and even with proper gloves, that metal will go right through them.

[@peetsnort]

I am using Khantal for the bad conductor properties for the handle of my portable griller. kzbin.infog_m2LNOg5zA?feature=shared The Khantal wire handles allow me to pick up the fire and control the air for flat out heat or simmering by placing it flat on the ground. Khantal wire is a very bad conductor so the handle is always cool

[@paulcottingham241]

5000kW is 5 mega watts.

[@jakobhalskov]

Oops :P Luckily I am not burning of 5 mega watts in my garage, yet.

[@jmikronis7376]

@@jakobhalskov, for 5 Megawatts, the local power company would have to install service that could deliver it. I doubt you could get that much service to your house. That’s industrial sized service.

[@AndyMcBlane]

5000 kW would be impressive lol

[@ImUpsetThatYouStoleMyUsername]

"Kanthal" wire. Sorry. It's on the paper at @2:07 I'm sorry does he say Kettle wire? Kentle wire? What material is that wire?? Candle wire? Sorry I am actually using this as a rough blueprint for my heater retrofit. Not sure what he is using here I'm thinking of using an 80% nichrome alloy wire