Adam Savage Upgrades His Lab Oven! 

Subscribe for more videos (and click the bell for notifications): ru-vid.com Join this channel to support Tested and get access to perks: ru-vid.com/show-UCiDJtJKMICpb9B1qf7qjEOAjoin

Retired lab oven engineer here ..Temperature uniformity is usually measured with up to 9 probes per shelf. An oven without an internal fan is usually pretty bad. A forced- air oven is the best. A vacuum oven is the worst. Getting good uniformity is the bane of every oven manufacturer.

*Personally* I would have put the readout on the front panel between the heat/cycle LED and the power switch. Could even keep the faceplate and just feed everything through a grommet. Such a nice self-contained area in that bottom compartment. But then I've no idea what to do with the thermocouple. Snake it up in one of the side panels and poke it through I guess.

Years ago, I used to use lab ovens of various sorts and sizes in an industrial hazards lab. We used to make thermocouples by the bucket load because we were testing for exothermic decomposition of bulk powders. I was once tasked with looking at the temperature distribution in some of the ovens and so constructed a framework which allowed me to position thermocouples around the oven and logged the temp over time. If I remember correctly, the non-fan ovens had massive temperature variations.

I work with extremely low temperature (

I'm only mid-way through this video, but I feel the need to throw my hat in the ring here. I work for an equipment manufacturer, and we have made laboratory ovens for many years now! I can often get my hands on some refurb units that are very well priced, and they have fantastic temperature uniformity, and they all come with digital readouts, etc. I also have a fantastic line of vacuum ovens, if needed. Feel free to reach out if you ever needed something like that, as it would be a dream come true to connect my work with the channel that I watch while I work 😊

Adam is single handedly keeping Snapple in business

Adam, If you have an instant read thermometer you trust, then set the oven at 200 degrees with a beaker of water inside. Give it twenty minutes to soak at the temperature and then measure the water temperature. That is the easiest way to test an ovens temperature without getting a certified thermocouple. Just check your thermometer in a bowl of ice water first to guarantee it is reading 32 degrees, meaning it is accurate.

I think that Adam missed an opportunity to placing the digital display in the false bottom in the black next to the other controls. Otherwise another great video.

You'll need to have the thermocouple probe all the way in the enclosure. You might need to have it fixed to the back wall or top wall. Also you might be getting different readings as your thermocouple probe is on top and the existing thermocouple probe is I would believe near the heating element at the bottom, you've also placed the oven thermometer at the bottom which is near the heating element. As there is no air circulation, you would not be able to get the same temperature reading at the bottom and top. This is because the power to the heating element will be turned off when the bottom thermocouple reads the temperature that you have set.

I was pointing at the front panel and saying "or you can mount it here" the entire time, but the look he had on his face at the end knowing he was going to be dragged by the comment section showed again how humble this gentleman is. Looking forward for an update on this project in a future video.

In the spirit of "anything worth doing is worth overdoing," I would have thought you'd use a PID with a proper thermistor at all three levels.

I have this exact same oven among a few more. I actually use them in a lab setting and the temperature swing varies widely as you will soon notice. I have added a digital thermal control unit with a solid state relay. It dramatically holds temperature better than the dial.

I love how enthusiastic the automated captions are about calling everything "[Music]" including Adam slapping things XD

I used a BBQ thermometer from lowes on my powder coating oven. Comes with thermo couple and digital display. Has input for 2 probes. Runs on 2 AAA batteries. Was like 17$ works amazing. 5 min install.

Now you just need to weather it.

Re: Fahrenheit, it wasn't a calibration error per se; zero was chosen as the freezing point of a 50% salt brine solution. Why that was chosen instead of plain water I do not know, but it was an intentional choice.

EMP button should be like a master switch for all the lights in the shop, great way to end the day. Something you interact with every day for that little jolt of satisfaction, but not constantly so as to wear it out.

Why , Adam, did you not put the instrument flat on the bottom black panel : there is plenty of space. Then you could use the same pass port the thermocouple used by the thermostat...

Thought I would pitch in with a bunch of information I have learned over the years working in environmental validation, metrology and service engineering in the Pharmaceutical science industry. Before you can look at calibrating your oven, first I think its important to understand the way this type of oven would typically control its internal temperature (I can not say for sure as I have never seen this exact model of oven previously but I have seen many like it) This type of oven has a "dumb" way to control itself. It supply's maximum power to its heating element until its internal probe reaches the set temperature then, it cuts power to the heating element which often creates a large overshoot in temperature. Once the temperature goes back below the set point, it will send power to the heating elements again causing it to heat again. This will make the temperature trace over time constantly cycle up and down lets say +/-10C (a rough random guess) This also explain as to why your temperature monitor kept turning on and off to start with as it was probably wired to the same power rail as the heating element. This can also be seen via the red light indicating heating on the bottom left of the oven. The temperature readout was on when the light was illuminated indicating heating on and the readout had no power when the heating light was out. Now onto measuring the temperature. Two of the most important aspects of measuring the temperature inside of an environmental chamber (in this case your oven) is air circulations and location of the control/measuring probe/s. Your oven may seem like a small space however even in this small space stagnant air can cause hot/cold spots across the oven which can vary greatly (like your seeing with about +/-10F). This is normally caused by the heating elements heating up the side of the oven first then that heat transferring into the chamber itself. Now, the thermal transfer of energy from the heating element to the metal walls of the oven is fairly efficient however, transferring that heat from the metal walls of the oven to the air inside the chamber is not very efficient so it takes time to heat up the air. As this air is stagnant, it is often warmer closer to sides of the chamber. This is also reversed on sides that do not have a heating element. The warmer air inside the chamber has to heat up the metal walls that do not have heating elements and that transfer of heat is not efficient either. This also explains why you was getting very different readings when you had your probe attached to the celling of the oven than when you had it hanging from the celling. Now, the control probe (the one that adjusts the ovens heaters) is often located near the edge the chamber and will typically heat up faster than lets say the air in the middle of the chamber. This is one of the reasons why you are seeing differences on all 3 of your temperature reading devices across the oven. Another is it seems as though none of these sensors are calibrated to a known reference standard so its impossible to say with any reasonable certainty which sensor you can trust. Even though some of these (likely the ovens controlling probe) have been calibrated in the past, temperature sensors are known to drift quite drastically over time often 0.2c - 0.5c per year. As your oven seems to be fairly old, this could have acuminated a large amount of drift I cant say for sure as I don't know the exact model of temperature reader that your TC is attached to however these type of readers typically only have a accuracy or +/-2C so from my experience so this is also where inaccuracy is coming from. The type of TC you use to measure the temperature inside the chamber can also matter depending what your looking for and what you care about in your process. The metal jacketed TC you have is great for stability over time, however it will be very slow to react. This means opening and closing the door wont affect it too much but if you leave the door open for 2 mins and the oven drops 50C, it will take a long time to measure the change. If you use a more traditionally welded tip TC, this will react much faster to temperature change as it is only measuring at the tip of the TC and a blow in the wind will affect the temperature readout. it all depends on your process and what you care about. For dehydrating food, the metal jacketed probe does seem more suitable overall. You could look at other type of sensors like a PT100 which is typically a lot more accurate however this is more of a pain to implement, more expensive and often requires an amplification circuit. The most important thing by far to get as even of a temperature across the chamber as possible is simply adding a fan inside the chamber itself. This does not have to be large or powerful fan however, it is incredibly important to circulate the air inside the chamber to get as stable of a temperature as possible. I have a lot of experience with highly accurate environmental chambers that often keep their set point temperature within the whole chamber of about +/- 0.2c and its always amazing to me that even though they can control, Temperature,CO2, Oxygen, Humidity and other environmental factors, the most important part is the fan. Without it moving air around the chamber constantly, it creates high and low spots of different environmental factors. You can easily tell when the fan has gone as the chamber starts to read very odd. long story short, my recommendations is adding a fan which can withstand the temperatures you require into the chamber will make it preform a lot better/make it way more efficient. If you really want the best accuracy, I suggest getting a calibrated known probe of a higher accuracy (typically 4x greater than the resolution of your probe) and measuring the center of the chamber With all of this said, there is vary few applications even in science where heating anything in a larger open air space like this +/- 10% of the set point makes a big difference when you get over 200C. Now at below 50c when your culturing cells in incubators or testing stability of samples in different simulated environments like a hot dessert or a cold frozen tundra, accuracy really matters but above this, I have not seen many cases where it needs high accuracy. If you ever want to know more about any measurement including mass, temperature, humidity, pressure etc or how the sensors work, feel free to message me

All that room underneath, where the controls already are, why not install down there? Follow the existing thermocouple. No dangling wires outside.

I've never shouted at the screen so loud at any of these videos! YOU'RE HOOKED TO THE LOAD SIDE OF THE STAT!!!!

Just FYI you cannot simply extend the cable for the thermoucouple. There are multiple reasons. One being that a thermocouple measures known mV changes caused by different expansion rates of 2 metals. The cable used to extend should be of the same type, eg. K, J, R, S, etc. Another issue is that every time that a you make a join, this join forms another thermocouple which affects the accuracy of your readout due to temperature being measured at various points and "fighting" each other. Also valid points made by others regarding actual placement of the probe, etc.

Your cleaning tip is such a fundamental element for any maker /tinker /artist Thank you for being a positive role model for those of us who recognize it

I really enjoy the acoustic stories Adam's hands tell us along the way.

the Walken "foo FIGHTers" out of nowhere was a pleasant surprise.

I bought a lab drying oven years ago and used it so often, it only goes to ~ 150C but made to be on 24/7 . Perfect for warming bearings, welding rods, ceramic tile pre-drying, softening polymorph. Double door with glass inner so you can view contents without letting the heat out. Inspired to make a digital readout for it. Nice work.

Two thoughts: One, it is clear Adam came up with an idea to put the work box and display on the door of the oven and got fixated on that. Two, as soon as he pulled the bottom off the oven, me and several dozen other people in the comments went....why don't you put everything in the bottom and put the readout between the temperature control and on/off switch. It's funny how that works.

I have a quincy lab oven like this and I took out the original control knob/wiring and installed a PID temp controller with a thermocouple. It gives you a lot more control and the PID controllers are not expensive.

I worked on deep space craft. The thermal sensor probably feeds an A-D converter. A-D converters are NEVER linear. We implemented a conversion function on each such sensor. If you want better accuracy put a micro computer in the loop and have a conversion function. I can send you code for the conversions if you are interested. I have it in Java, Ruby, Python, Perl, and C with a little searching. You did good with using more than one temperature for calibration. Any sensor that is not calibrated is worthless.

Why not just mount the thermometer in the space on the black front panel, between the thermostat and the power switch.

The fact that Adam apologizes for the Fahrenheit system and then gives us a history lesson is why we love him.

As someone who has worked with these exact ovens and verification/calibration.. The position of the Thermo is important.. Also, use a accurate external thermometer and just put some mark on the dial to indicate the temperature.. We used different colored paint and wrote it on a 3x5 card attached to the door.

I made black garlic using a rice cooker set on warm (about 140°F). It took about a month, and boy was it fragrant for a lot of that time

Adam needs to try being Canadian. I am 5 foot 10, it is -3 Celsius outside, I set my oven to 400 degrees Fahrenheit, and I drive my car up to 100 KM per hour….and I weigh my self in pounds.

Man.. I was trying to make a black garlic powder unsuccessfully for three years! I kept wondering what I was doing wrong.. it must be an issue with Vegas’ lack of humidity. My grandmother made this delicious black garlic butter bread.. I eat a ton of butter bread- but it just doesn’t taste right. The ovens are too expensive- I’ll just stick with my regular oven and work with some humidifiers to try to get that recipe right! Gratitude

To get an accurate temp the thermocouple need to be in same position. There could be a temp variance from top to bottom of cabinet. Depending where the product is in the cabinet I used to have temperature sensors around 2/3 up from bottom near the rear allowing for thermal circulation. I am 74 and enjoy watching Tested.

My dad grew up with imperial units (we're Canadian), but we use metric now. For a long time he said he would like to be able to change it in his brain, but he just couldn't do it. Then he got a thermostat that just showed both F and C at the same time, and just seeing that conversion every day was enough that he can now comfortably use celsius.

The standard monitoring technique for these cheaper ovens is an old fashioned glass thermometer (~350C) wedged in the hole in top. I can see the advantage of the digital display, but in terms of calibration I'd stick with the glass to get your "accurate" reading...but even then, as you noticed, there's a strong temperature gradient between top and bottom internally. Nice idea with replacing the main knob, if it's anything like ours the little grub screw doesn't have a particularly strong grip and it's easy to torque out of whack, I always double check the end points of the rotation are where they should be before doing anything particularly temp sensitive. Given the range of failure modes I'll sometimes have a "dummy run" with a spirit thermometer in the same place as my test subject, e.g. if I'm incubating petri dishes at 37C I'll load it up with blanks and check the temp variations *for that shelf when loaded* every half hour for a few hours. (Yeah, they're good at maintaining lower temps...if you can work out the dial setting, it becomes more tricky the lower you go.)

My powder coating oven is the gutted shell of a clothes dryer that I insulated and transplanted house oven guts into.

Used em very often in Organic Chemistry research labs, drying glassware and molecular sieves.

It's uncanny how either Adam or I Like to Make Stuff puts out a video the same time I'm tackling a similar shop infrastructure problem. I have a lab oven (from ThermoFisher) that I've been trying to make useable for my needs - and I too don't have a temperature readout! Been looking into high-end cooking thermometers (like for commercial ovens). Excited for Adam's solution!

Always find it admirable how willing Adam is to drill holes in really expensive equipment.

I know a lot off people would probably say something about how you do your work. There's nothing I can say but go ahead and keep it up because I would do it just as you do. GREAT JOB ADAM

If you don't need to get too hot a used food warmer/oven is a good choice. I have one that used to keep pizza hot. Now it tempers my steel. It is essentially exactly this oven, just for food so it's not quite as well built.

You should have seen the sign of the lab ovens I had to use, 1 was 2.5 ft tall inc the base. Another was 5ft long about 2ft high for drying aggregates and limestone and sands and filler dust. But put it on , on a winter days you didn't want to move lol (UK winters)

I think you should pf went with a PID and put it next to the stock red light. With a pid you can progran the ramp up to temp time, how long to sustain the temp, and to drop temp at whatever rate you chose, among other things...

Thank you Adam. I was today years old when I learned 212-32=180

For $20 to $30 dollars you could have replaced the old temperature controller with a digital controller which would provide the temperature display and many more features. I found an Omega industrial controller which normally sells for $200+ on e(vil)bay for $25 with shipping. The controller runs off 120VAC (no need for an addition supply), will switch 40A heaters and includes programmable functions like temperature ramping which is helpful when dealing with some materials.

Love watching your videos Adam, shows that you love your fans enough to envolve them with your projects, James from Scotland

Industrial Ovens are no joke. They are a huge part of the semiconductor manufacturing process so tons of second-hand options if you know where to look.

I was always told to use redundant instruments only in critical applications and, even then, to designate a primary. Otherwise, operators never know which one to believe. 😆

At a previous institution I managed thermocouples inside a CIGS reactor chamber. This brought up some good (and painful) memories. I think what you need to add to your shop is a thermal calibrator. I have one, an Omega CL3515R. Such a cool device for checking and setting up an oven or other TC-readout systems! Also, get yourself a roll of Type-K wire :)

We have tons of those exact ovens at my tech job for curing and testing electronics for aerospace

I winced when you started drilling into the body of the oven. It's that moment of "commit!" That happens for me even it's happening to you. Brovo! I have no temperature expertise to bring to this endevor, only my respect.

Interesting weekend project. Lab oven is a great little tool. It was a bit hard to tell from the video, but NTC thermistors (often encapsulated in glass), provide very accurate temperature measurements with minimal drift-typically within a tenth of a degree. Just cost a few dollars. In contrast, thermocouples, which rely on dissimilar metals, are less precise and can drift over time, with accuracy around +/- a few degrees Celsius and most likely what you have. For geeking out on lab ovens you can for enhanced accuracy, might consider configuring your sensors in a Wheatstone bridge or integrating an additional sensor, and if you're using the oven for processes like curing, it could be beneficial to implement temperature profile controls. For instance, you could set it to maintain 150 degrees for an hour, increase to 250 degrees for four hours, and then gradually return to room temperature over twelve hours. Probably some free arduino projects that exist. Anyway love your videos.

They used high-temp wire, I’m not sure that I would have used lampcord, and also screwed the power supply to an area that looks like it will get fairly warm. If you want accuracy, you need something with a Pt100 type sensor (3-wire) and to hang the sensor near the middle. But that type of sensor and the unit to read it would be significantly more expensive. You might also want to put a fan in to blow the air around, at least for testing purposes.

Hey Adam, I've been watching my way all the way through Mythbusters and just got to Lead Balloon. I had forgot how mesmerizing your cube was. Not to mention how much I can actually remember from watching Mythbusters as a kid.

Much like baking in a home oven, radiant heat from the element vs ambient heat in the air, that's why your biscuits burn on the bottom before the tops brown if you don't use a hollow baking sheet or a second baking sheet on the rack underneath. Put the oven thermometer on the top shelf and a pan on the middle shelf (or other metal to shield the radiant heat) and check again.

OK so why on the DOOR which will have mechanical force applied against the wire when opened and closed, and not at the control panel bottom, where all the controls are?

3D Printed project boxes are awesome. Easy to size however you like, and trivial to make whatever shaped holes you need. Can also 3d print grommets to protect the wires from sheet metal.

If you want to get all fancy, shmancy, you could get a NIST traceable calibration heat block to make sure the thermocouple and readout actually are reading the temperature properly. Of course, for $3000, you could probably find much more fun things to buy!

You can make black garlic in a slow cooker leaving on low for 2 weeks also.

I can see the follow-up video already: Remounting the Display on My Quincy Lab Oven. You really should mount the readout and thermocouple lower, on the panel. Not sure the hobby box is needed, or the right call for a lab oven.

Like many others, I would have mounted the read-out on the bottom panel between the temperature selector and the power switch and avoided all that mess with the external wires and holes in the case. Then run the sensor up into the oven through a small hole in the bottom to keep it all neat and tidy.

Don’t quote me exactly in this because there are a thousand better sources but the use of 360 and 180 etc is actually really smart because in the days before calculators, things measured with these number systems were very easily divisible into halves / thirds / quarters / fifths / sixths etc. In other words it has many more complete simple divisors. I believe imperial measurements also hark back to this but again, others will explain it better or more completely. Thanks as always mate, love your stuff!

I see you walk back and forth to your drill bit index to your fractional drill gauge. I’ve attached mine to my drill index itself with small disc magnets. Saved me steps. Just an idea.

Hey Adam. With regards to the kitchen dial probe... If it has adjustment then you can just boil it then turn the screw on the back to correct to 100C or 212 in Yeehaw units.

I'm from Canada. We use all the systems for measuring various things. Height: Ft/In. Weight: lb. (unless you are buying lunch meat, then grams) Distance: KM. Weed: g OR oz.

Hey Adam you could have use a Dremel cutting wheel and made a hole in existing lower control panel and mount the Temp display there. Then Drill straight up into the chamber for the thermoreceptor - I have a friend I helped do exactly that and it looks like it came with it!

Custom printed project boxes are one of the reasons I was very excited when I got my 3D printer. I understand it looks like Adam had one on hand, however, the custom route would allow a smaller enclosure tailored to the exact measurements you need.

Say whatever else you want but a thermometer that uses F as the scale instead of C has more increments of temp between freezing and boiling which makes each increment more granular than C which can mean it is more accurate- even if the math is not divisible by 10 - anyway it should all just switch to K (and talking about normal home use where you only get limited accurate readout - of course if you have 4 or more significant digits on a lab calibrated C thermometer it is very accurate)

It reminds me of a saying I once heard and I just learned is called Segal's law: A man with one watch knows what time it is, a man with two watches is never sure. in your case, you have three. I always enjoy watching you.

Just to be different, I'm gonna say that where you put the reading display on the door is perfect. Much easier to read and no need to bend down to see it.

adam: i dont want to put shop stuffs in a food oven also adam: I'm upgrading this shop oven to put foods stuff in

Agreed I was shouting all that room underneath and the power connector let alone already area for a thermo couple.

Great job. Thank you 😊

Put temp display on toe kick. Less wires on outside and a cleaner polished look. Great Video as always Adam!

We have the same oven for Cerakote. Only issue I’ve had is at 350 if I don’t keep a fan blowing on it to circulate air under it…it will pop its safety. Took me a minute when it first happened until I flipped it over n opened the bottom to find the reset switch.

Did about the same thing you did for a draw oven. Got a Blue-M lab oven from HGR Industrial Surplus in Euclid Ohio for a hundred bucks. Then I got a cheap-o PID and SSR off eBay for somthing under 30 bucks. - It's about the same height and width as yours but is like twice as deep. - I can push it to a steady 600F and it will draw back 4140 parts all day long and holds +/- 3 degrees. - I got less then $150 in the whole thing. I highly recommend anybody needing a draw oven to check out HGR - Even with shipping you are money ahead of "toaster" ovens. You can use it for powder coating, and it's an actual industrial piece of equipment.

I was a commercial kitchen appliance technician for 6 years in the Bay Area. I’ve learned a lot on troubleshooting complex Ovens and warming cabinets. I found that ovens that don’t have a convection fan won’t have even heat. I noticed Adam having his temperature gauge at the very bottom, as for his probe being at the top. This will cause a few degrees difference when testing. Even with the heating element at the very bottom temperatures won’t be consistent unless there’s a fan circulating the air inside the chamber. Hopefully this might help.

Why did you not put it beside the power switch instead of where you did?

First: why did you put a control panel display on the door instead of what seems like the obvious place... the control panel? Second: did you wire the display's 12v supply to the thermostatic switch so it only got power when the oven was heating?

I, personally, would have put a PIC controller in it. A very nice display, configurable temperature swings, able to be calibrated, and it would look factory. I just added one to my filament dryer.

Love the video , the oven looks great Adam .

I'm American & now I have to go down a Google rabbit hole about Fahrenheit vs Celsius so I can learn the history of it. It actually sounds pretty fascinating😂 I swear I'm such a nerd🤦

Make sure you use high-temp RTV gasket sealer or something to isolate the temperature creeping from the ambient air into the coupler. You should also insulate the wire with fiberglass so the wire does not diffuse the heat into the air, which may alter the readings. As for the temperature values not being matching, that is expected in an empty oven where the element is on the bottom as well as the controllers sensor. The heat that has risen off the element will naturally be hotter and collected, before the lower elevation sensor can "adjust" the temp to stop heating. With a fixed-body mass, you should get a decent average temperature. It is the same reason that an empty fridge is harder to sustain temps than a full one. In an empty fridge, there is no mass to act like a buffer for temps. Opening the door will instantly dump the cold air out and replace ALL air with room-temp air, demanding a bounce-temp adjustment. As opposed to a fridge full of water jugs that has half the volume lost and 1000x more volume-mass of stored "temperature buffer", to assist with restoring the half-volume into being "up to desired temp". Adding a fan in the unit would assist with thermal control. Instead of convection, it would use forced distribution of air, like an air-fryer would use. Temps from top to bottom would be mostly equal and change slower. If the sensor for the dial was included in the path of air motion, it wild also assist with better control temps. I would have just put the gage on the front panel, where the switch was at. Adding a Celsius gage later. The thermal-coupler could also have been put on the bottom. In all honesty, just checking a solid mass would have been enough to satisfy the test for calibration. If the dial was true and the temps were sustained, then none of this was "needed". Never trust a manual bi-metal oven temp thermometer. They are ballpark from the factory and in time, oxidation makes them more horribly inaccurate. They would all need to be individually "calibrated", and they would need to be sealed in a nitrogen gas chamber, to be remotely close to any real temps. (Your "Farenheit" story should have answered that question for you.) You don't need a large fan to circulate the air in that tiny space. However, you want to make sure it is designed for 600+ F temps, if your oven goes to 450F. (To get to 450F, the element may reach peaks of 600+ F. Unless it has an economy element that pulses with a slightly lower temperature. You can actually use an AC PWM to make a slower heating element. Slower may be more economic and more stable of a transition, but it can ALSO make opening the door more of a burden to recover. You may also be competing with thermal-losses through the case, which could negate any gains from using a slower heating element. A micro-controller to control PWM, like with a "battery charger", would adjust the pusles to be shorter when near temps and be full-power when far from desired temps.)

STC-1000 Digital Temperatur Regler Temp Sensor Thermostat $25 -$30 on fle bay. well suited to a ceramic reptile heater bulb to make giant dehydrator

Pronouncing ‘Foo Fighters’ Christopher Walken-style made me realize we’re pretty close in being in the same RU-vid-Rabbithole 😂

One of the things to understand about Fahrenheit is that setting your initial standard for an earth centric temperature scale is very hard, and "water freezing" is not consistent unless you have very pure (distilled) water, so 0 ended up being set by a brine which is more easily replicated by other people as you can just make a saturated brine and it will (effectively) be the same every time, toss in a bunch of ice and extra salt and your reference will be much more consistent. Functionally, both Fahrenheit and Celsius are wrong, as either Rankine or Kelvin actually translate to heat transfer in a much more meaningful way, but both are effectively random scales humans pulled out of our posteriors. Imperial force, mass, and length measurements are where everything sucks. Pounds mass vs. force was the point where I just decided to do everything in metric because it confused me too much and converting was going to lead to less errors. If you want to do a quick calibration on your thermocouple, I would suggest using boiling water to set an initial calibration point.

Everyone talking about the area down by the controls for the readout... 1. It depends on where the item is placed. If that would end up being at waist height you probably don't want it there vs. something closer to eye level. 2. It makes running the thermocouple harder (which can be worked around) but still.

Hi Adam. Would like to recommend the wago connectors. Much better and safer than the screw-connectors imo. But who am i kidding, you prob have 2 sortimos full of them lol. Love the content buddy. Happy easter everyone

I agree the I would have installed the display in the front control panel. I am assuming that Adam wanted to use the oven’s existing thermometer hole in the oven, so that is why he had to mount the digital thermometer higher up. As for the thermometers reading differently, it is all about placement of your probe/thermometer. If you could mount the display in the lower panel and colocated the digital thermometer’s thermocouple with the oven’s control thermocouple you would likely have the two reading the same. As for the oven thermometer, try placing it higher up in the oven. Closer to the digital thermometer’s probe. Also by any chance do you have any Bakelite or teflon tubing? That should hold up better than wood as your thermocouple insulator.

In the laboratory, those ovens are typically used with an external temperature probe because, as you saw, they are not perfectly calibrated for every possible temperature over a range you might use. Also there is temperature variation from top to bottom and left to right by a few degrees, so depending on where your thermal couple is you may not be getting the exact temperature your sample is experiencing.

Your always good for knowledge and a good laugh.Thank you.

One of my favorite sayings: A man with a watch knows what time it is. A man with two watches is never sure.

Great little oven use one all the time at work, just stay away from putting anything directly on bottom rack gets mighty hot. Right above the heating element.

Thanks for information Adam an Tested Crew

Calibration related: The controllers thermocouple looks like it's in the bottom, while your measurement one is in the top. That could easily explain the 5~10° difference without some air circulation.

When I first clicked, I wondered if you were going to replace the controller with a digital one. I have an old analog Kiln from the 70's that I would like to upgrade someday.