Making a High Temperature Electric Oven for Heat Treating Steel!!

www.PracticalRenaissance.com
I wanted a small high temperature oven for heat treating steel in my home workshop, so I built one out of some basic electrical components, insulating ceramic bricks, and metal!
As promised, here are the parts I used:
PID Controller w/ 1 Relay: amzn.to/2Mv4uvQ
2nd Relay: amzn.to/2sWk37S
Relay Heat Sink: amzn.to/2Mpeirk
Kanthal A1 22ga Heating Element: amzn.to/2JBAaBX
Ceramic Terminal Block: amzn.to/2JPgOZw
High Temp Wire: amzn.to/2ybShtf
K23 Soft Insulating Firebrick: ebay.to/2HOCgZJ
Complete Parts List excel file: bit.ly/2Nm2FBc
Kanthal Calculator excel file: bit.ly/2NVCQsX
PATREON bit.ly/28X4419
INSTAGRAM bit.ly/1NLu9zv
SUBSCRIBE bit.ly/1OAKcuw
FACEBOOK bit.ly/1YDV3d5
TWITTER bit.ly/1ToGKYm
Camera: amzn.to/2sXCWaq
Microphone: amzn.to/2MpiMOC
TIG Welder: amzn.to/2JJjkxb
Mill: ebay.to/2y7Ximm
Mill CNC Conversion: • Grizzly G0704 FULL CNC...

[@kaminmiller]

I dig it. I'll have to try to make one of these for my home shop when it gets finished.

[@GregsGarage]

That came out like a dream Jeff. I'm looking forward to the projects you will wind up putting into your new oven.

[@joandar1]

Good project, Great Result! Another for the Bucket List. Thanks for uploading, cheers from John, Australia.

[@unclebobsworkshop1865]

Hey Jeff, Thanks a bunch for this video. I have a heat treat project that I really want to do, but it's been on hold for a couple of years because of the cost of commercially built ovens. I'm inspired again! thank you so much.

[@Karateka95]

Awesome video man! Thanks for sharing! Your clear documentation and explanation of the process has really helped me in the planning of my own oven!!

[@KatyLynnWinery]

Just what I have been looking for. I will be using your plans for my own in the future. Thanks.

[@RRINTHESHOP]

Came out great. Very similar to what mine will be. Enjoyed.

[@PracticalRenaissance]

Thanks Randy! I look forward to seeing yours!!

[@rickpalechuk4411]

Very nice project Jeff, I like the angled design of the control housing. Good first build to work the bugs out, I'm sure you have inspired others to create their own ovens. Great to watch, keep them coming. Cheers

[@PracticalRenaissance]

Thank you!

[@alphabob8156]

Nice work! And nicely equipped shop - make sure you utilize it to the fullest extent!

[@sharkrivermachine]

Great video, looks like another project to put on the list.

[@PracticalRenaissance]

Thanks! It's not that hard to be honest, and I'm glad I have it now!

[@shawnmrfixitlee6478]

Now that is EPIC AWESOME .. Keep the Cam going man We miss you !!

[@PracticalRenaissance]

Don't plan on stopping, I just get slowed down sometimes :)

[@joell439]

Fantastic. Thanks for all the descriptions and design details. Joel....

[@yosmith1]

Great project, thanks for sharing

[@theravinglunatic470]

I really enjoy your videos man. I gotta say I've tried and failed at this same project 2 times already, I think this video might make me go in for a third.

[@PracticalRenaissance]

Thank you! I wish you the best of luck if you try it again, email me at [e-mail] if there are any specific questions you might have, I can at least give them a shot!

[@jacquesbouchard8884]

I really enjoy watching a skilled person working! I just don't have the patience to do that ! Great video sir ! And the bass clef suggest that we have a passion in common !!! ;-)

[@jimmynoname336]

Nice little oven bro ? I'm gathering my supplies trying to learn from everybody. THANKS FOR FILMING THIS!

[@ifell3]

I love it, not the first I have seen but your delivery was second to none. I've always been a bit sketch about getting things in and out whilst on incase of touching a coil!! Would have to turn it off every time!!

[@PracticalRenaissance]

Yeah a switch on the door would be easy to do, I just skipped it since I'm the only one using it and I play with my fun little on/off switch every time I open the door :)

[@ernieengineer3462]

Great project and great presentation. Keep it up.

[@AmateurRedneckWorkshop]

That turned out really nice. Definitely a first rate oven.

[@PracticalRenaissance]

Thanks Harold!

[@DudleyToolwright]

interesting project with a easy to follow explanations. Nice.

[@EmmaRitson]

very nice. thanks heaps. great idea for a spring winder!

[@artamsler4053]

Nice work as usual, keep it up.

[@johnjude2685]

Thanks for your information, This sounds great

[@SilverSin]

Great lesson. Keep up the good work!!!

[@FilipHuzjak]

Great video, very informative. thank you!

[@TimeSurfer206]

Stopped in to scope your design out for small scale pottery. Looks intriguing, and could even do Precious Metal smelting, easily!

[@shaynut6]

Great video. Planning to make one soon!

[@SolidRockMachineShopInc]

Nice Job! Steve

[@aijazahmed9113]

Wonderful job

[@killerkane1957]

Great job! I bought a big Paragon Heat Treat oven. But you have the satisfaction of building your own! I just wrote a check. Not much fabrication pride in that!

[@robert5]

time or $$. you had the $$ nothing wrong with that, its what we are all working toward.

[@marcsenteney3160]

Well done sir!

[@wireedm1]

Excellent video, thanks for posting!

[@jerryquigg3497]

For electrical isolation I use a combination of a SSR driving a DPST contractor (relay) to power the heating element. As others have said, for safety, a door interlock to isolate and disable power to the heater is also advisable.

[@twisterwep]

you're a good man, thank you.

[@janlassen6101]

Thanks for showing what electric stuff is needed to buy and where to buy it.

[@mrdelete8660]

It's funny watching you explain why and what your oven is for, all while wearing a brownells apron.

[@mememaster147]

Love your toolholder rack at 2:10

[@YourOldDog]

I watch KZbins all evening preferring it over television. I can say you made a great video in every respect...........I didn't have to watch it at double speed !! LOL Count me as a subscriber.

[@asheshshrestha]

300 likes 0 dislikes... the video is super interesting.loved it

[@BuildSomthingCool]

Just watched several of your videos. Great channel you earned my subscription 😀

[@PracticalRenaissance]

Awesome! Thank you very much!

[@pankajsoniii]

great job brother

[@PaulSteMarie]

Great video!

[@tylerkrug7719]

That thing is sweet!

[@k5at]

Great project. I like how you made the frame. I built my own control box using an arduino uno. It works great and reads in degrees F.

[@PracticalRenaissance]

Oh that’s clever I never even thought of using an Arduino!!

[@jmortonsalt]

Could you share your wiring diagram & Arduino sketch?

[@DreamsOfTheMind-video]

Love it, nice work!

[@roleic7246]

neat project.

[@Hirudin]

Damn nice job!

[@randysmith106]

That turned out great man! Awesome job! Gotta say I'm a little jealous too... Its on my list of things to make but there are other projects that must be made first. Ugh..... only so much time in the day (sigh)......

[@superdave2112]

That was SO awesome! I need one. Well, want. Thank you! So do you slap da bass?

[@westcoaststacker569]

Thanks for Sharing.

[@robmckennie4203]

Took me a second to grok the use of 2 relays, but then it clicked, north america -> split phase. Oven looks good, i'm thinking about building my own in the coming months. My house just happens to have 240v 3 phase, so I might just take advantage of that to really make it sing

[@mrstephenporter]

Great video

[@deepbeeps]

Thanks for including some of the issues you had, like the coils coming loose. I am in the process of building a pottery kiln. Pretty much the same design as your HT oven, just a little larger with 4 coils. Now that it is finished and used, is there anything you would have changed?

[@urizon41]

This is a great video! Im at the point where i want to control my heat treat better also but im torn as to make one or just buy one. When i had tons of free time i made my own 2x72 grinder, but now i almost dont have time to even make a knife let alone a oven.

[@CuriousEarthMan]

I saw a used kiln/oven on craigslist that worked fine, but could be upgraded with a PID controller....$225 asking. 9"x9"x6" inside dimen. hard to beat. so maybe look for a used one to upgrade?

[@Machine_NZ]

Hi Jeff, excellent video and learn't quite a bit. Regards Kevin

[@CuriousEarthMan]

I thought this a really great video! Something about your style fits the questions in my mind. Lots of practical detail! Thank you! I'm wondering one thing, though: for someone with as many advanced skills and tools as you have, if a putty knife or small trowel might have helped you in your mortaring of the bricks? Not a criticism, just wondering. maybe you like to feel things. I know I do sometimes too. You make it clear to me where I need to study up, and I picked up clues from how you did things....considering ohms was a missing link where I knew I needed to know something more to buy my wire and calculate length, but wasn't sure what the missing factor was! Thank you again!

[@DimaProk]

Nice! I think we operate on the same wavelength lol, it started with Grizzly 7x14 when I first saw your channel and I had issues with mine, than you threaded a marlin, than you did muzzle device, than you got South Bend at some point you got milling machine and now you build high temp oven. I did all of that as well just not as elaborate and fancy and I didn't even see what you did only saw it later :) I've had firebricks and wire sitting in my garage for couple years, I've been putting this project off for a while, I actually been using my pineapple can forge to heat treat couple dozen of small parts with ease. I want to build electric metal melting forge to melt zinc and aluminum and possibly brass. I noticed you used same brand of wire that I got except I got mine in 16 gauge as it's not easy for me to access 220v so it will run on 110v. I've been looking at same terminal blocks on ebay but the ratings are confusing. Some sellers list it as 5A only and some higher so I didn't know who to trust. Regarding PID the first one I build for my lead melting pot about 3 years ago I also ended up with one reading in Celcius and while it worked great I found it annoying so I bought MYPIN and it can read in both, it also has 2 rows of display, I like it much better. It only $20 on ebay. I also noticed all people used more liquid dark grey cement to "glue" the bricks, it's more liquid, I'll look in to that. Another thing I was trying to find was ceramic tube insulators for wires coming out the back, but I guess it's not really necessary.

[@flat-earther]

Man that was awesome, I wish I had the knowledge to comprehend the electrical components though.

[@done643]

IT IS VERY GOOD!!!

[@brentbogy9894]

Great video I’m looking at making one to hear treat knives. Have a few questions. Yours still going strong. ? Anything you would change? Did you use the cement because it’s not totally enclosed by metal? Thanks for the build and info

[@mrgreenswelding2853]

That's great! It could even melt aluminium and copper.

[@stemer1149]

Excellent build. I was eondering why you are using two SSRs to switch both ends of the coil, security reasons? I have built a PID controller for my LEE pot using just a single SSR (basically the same application). The phase is switched by tje SSR, the other end just connected to neutral. The main power switch double pole, of course.

[@Directionalengineer]

Vegoil guy watered down the refractory cement in his project... it painted on really well

[@Darthreloy]

You are like a half a brick away from making the best home Pizza oven ever! I see these guys build a behemoth wood fired pizza dome out in their back yard. So if they just want a simple pizza, its only worth the preparation and wait time to have multiple people over for many pizzas. It takes like 3 minutes to cook a nice pizza in a 900 deg oven. With your invention adapted to size, you could still use it for work, then at the end of the day, throw a pizza in there man.

[@clintonshank5137]

Love this video and plan ona build, is it possible to make one of the for 110v?

[@tecktake]

Hello, thanks for this video! What is the max temperature can it go till?

[@joeydubbs763]

Nice👍

[@NemecJesse]

I really appreciate this video and all the info you shared!!! How is the accuracy at lower temperatures? I just built a VERY similar oven and I'm having a difficult time with the temp reading... I have the Inkbird PID that will display in F/C, but other than that, its nearly identical to yours. However, room temp is reading about 150°F, when it's actually about 60° in my garage. I swapped to another K thermocouple I had on hand and have the same result +/- 1°. The Inkbird instruction manual is a joke and not much help. Is there a way to calibrate the input?

[@Steelcrafted]

Man even with a gas lens, your tungsten stick out is insane lol

[@eric802]

Very nice, as usual. I noticed you were using the SB lathe on the handle - do you ever use the lil' Grizzly anymore?

[@PracticalRenaissance]

Good eye! Yeah the South Bend is easier to keep ready to go for most projects but the little grizzly is still in the shop and plugged in! You can even see it in various background shots I’m sure, it lives right next to the other lathe

[@Delerium82]

I have a couple suggestions that might help you out with the coils but I’m not an expert by any means so take it for what it’s worth, we have banks of muffle ovens at work and they all have a layer of refractory over the top of the elements it gives them a layer of protection and I’m assuming would help hold the coils in place? Also there are interlocks on the door so you don’t have to remember to shut the power off while loading unloading.

[@PracticalRenaissance]

Thanks, that's a great idea that I thought about, but I went with the staples so that if I had to ever replace the coil, hopefully it'd be easier to do. I also thought about the interlock, I've seen some people include that, but I avoided it for simplicity's sake in this project. Thanks for watching!

[@rezaahmad463]

@@PracticalRenaissance can you forge by this or not???

[@Raul28153]

so it's been a couple of years what would you have done differently? Maybe thicker Kanthal and more of it to get the same ohm resistance? What was the over all ohm resistance for the length of wire you did go with? A heat up time of 15 - 17 minutes is really good. You should be happy about that.

[@Ltrain660]

One trick with refractory cement is that you normally want as small of a junction as possible not like mortar you would see normally between red bricks. The refractory cement doesn't have near as good thermal properties and sounds just be used as a glue more than anything

[@NemecJesse]

In reviewing your Kanthal Calculator spreadsheet, what is the unit of measurement for the "length of coil at wind size" and what is that specifically referencing? it would appear that the total length of coil that you installed in the channels you carved was roughly 50" or so by rough estimation, but the value in the spreadsheet in 16.

[@oniesma]

Same question here. No unit at all. And refering to your question, there is also no aswer at all.

[@rustbeltmachine]

It's in inches. Looking at the example (start with 33 inches of wire, end up with a 17" coil). Think about it: The mandrel is 0.156" OD. Multiply that by pi and you got 0.48 INCH needed to get around the mandrel. 33 inches times 0.48 is roughly 16 or 17", which would stretch out a great deal for install.

[@thetinkerist]

Thanks for your build log, I'd go with confining the coil within its own space, no staples needed, and yeah man you can weld :) aluminum welding, it like playing with butter. How are your coils doing after 5 years?

[@samuelef.m.sicali194]

Great project! I'm using it as a base to develop my own heat treatment oven. I have just one question: how come are you using 2 SSRs? I will plug my oven at 220 V socket. TIA!!!

[@jagu4r82]

Ciao Samuele, vorrei realizzare un fornetto anch'io. Sto facendo la lista della spesa, tu sei riuscito a trovare tutto? Non capisco perchè usa 2 relè... eventualmente hai un contatto dove ci possiamo sentire?

[@title1091]

Do you know of an expensive book, or some place I can find referenced information on what temps to heat treat or weld temps for various steels? I'm planning on making my own forge and have no idea what temps it will be experiencing or what to get for thermometer.

[@aaronclerigo754]

how did you test your kanthal wire? Im gonna test mine to just to get a feel of how high it can get. Thanks

[@Epiphalactic]

You can usually use water to thin up refractory.

[@andybrock100]

Make sure, if you haven't already done it put a switch on the door so when you open it, it kills the power to the heating coil. Sooner or later you will touch the coil as you take metal out of the oven and BOOM you could be history!!!

[@felixsu375]

What did you do to make the PID go through the tuning process?

[@shauntucker5145]

Thanks been considering doing something similar. can't wait to see how this holds up. Why does the thermo couple go into 2 spots on the pid?

[@PracticalRenaissance]

I wish I knew enough about it I could tell you, the wiring diagram is just from the instruction manual so I just did what they tell me....

[@michaelharris679]

My best guess is that it provides an optional way to ground the TC while still letting you do something a little less conventional.

[@thomashackerforgedknives2533]

How far does that thermocouple need to stick out? I'm wondering if I bought the wrong one. Mine will only stick out about an inch or a little less.

[@JR-pr1xh]

Neat.

[@millersmojo]

Where did you get your thermocoupler probe? Or is it the one that comes with the pid?

[@mikecrump1500]

Can you tell me what electrical components I would need in order to make a 120v oven? Thanks!

[@farhanaja100]

where you attach the coil? so it can glowing like that?

[@steveeb00]

Could you possibly save your excel file as 2003 Excel for those with older versions ? TIA

[@shanedurham894]

Amazing project and something that I need but never thought of building myself. What would you estimate the total cost of the unit ended up being?

[@craigwilson8255]

He said about $200 in a comment. He had some steel already.

[@frostroxie2740]

They make metal blades with diamonds for your chop saw..... also easy to make Foam Crete would make a great 2 Nd layer of insulation!!!!

[@k192447]

bem pratico,mas tem que se cuidar muito do modo como se instala o elemento de aquecimento.

[@skyrise666]

Why did you use two relays? I think one SSR on phase wire would be the same! However great job!

[@stephencollett6962]

Just add some water to the refractory cement if it starts to dry out.

[@Freizeitflugsphaere]

Hey dude! Nice video! Just one question left: why do you use 2 ssr relay's? I have seen people just using one🤔 Thsnk you!

[@jakelevis8453]

I believe it’s because he’s using 240vac rather than standard 120vac so he uses one relay per hot conductor

[@Freizeitflugsphaere]

@@jakelevis8453 ist this because the ssr's he uses are rated for the 120 volts? Cause I have 230 too but mine are also rated for it so it should be fine using just one?

[@TheMrconquerant80]

Hi, how did you calculate the wire diameter needed, how to choose the right one ?

[@kentvandervelden]

Awesome Jeff, you make it look simple! Have you tried melting aluminum? With regards to efficiency, how warm does the outside get? Ignoring time, how does the cost of home built compare to purchase?

[@PracticalRenaissance]

Haha thanks Kent! It was a few days of work, to be honest the most difficult part was probably sourcing all the parts :) I'm positive I could melt aluminum and possibly even brass in this oven if I wanted to, but I just built the foundry which I think will be more useful for that. I actually forgot to include footage of me taking the temp of the outside of the oven (d'oh!) but for the first half hour to 45 minutes it stayed ambient temp on the outside (which is in the upper 90s here in Kansas City in July) after turning the oven off I measured the outside about 2 hours later and it had risen to just over 200 degrees (F) so it's definitely not perfect. Total cost was just a bit over $200 all told, some of the materials I had on hand (most of the metal) and I think it was probably about 20-30 hours of total work.

[@grntitan1]

Very nice and uhh....."practical". So when are you starting mine? Checks in the mail.

[@Strawdozz]

How is it holding up? Are you still using it?

[@brunerfacascustom7035]

for a 150x150x600mm oven at 127v voltage so that it reaches a temperature of 1100 ° C which power and wire do you recommend?

[@FerretPirate]

For future reference, an easy way to remove the zinc from something is to soak it in vinegar overnight.