Always producing high quality, interesting videos throughout all these years. Applied Science is one of those KZfaq treasures, you know?

Excellent idea, that would be real handy.

This seems amazingly cool. In another thought, having glassware that can log how many cycles it's had gives me visions of DRM glassware and Dymo style lockout shenannigans.

I'm glad you are making this open source. Thank you for your work and content. You are my favorite content producer on YT for certain. Some things are way over my head but your explanations and failures/attempts make it for a very understandable 'product' in the end. THANK YOU. From Canada with love brother! Take care!

this is really cool. cant believe no one have done this before it seems really useful

To anyone wanting to reproduce this... while the eZ430-TMS37157 dev kit is no longer available, you can still buy the TMS3705 which is the main component used on the "base station" (reader) PCB. There is also appnote SCBA031 for adding a MOSFET driver chip for longer range. It might also be possible to source the MRD2EVM reader which is similar, or RI-STU-MRD2/RI-SMD-MRD2 modules. I still maintain a bunch of 134.2kHz RFID readers in penguin monitoring systems.

I can't even count the number of times something like this would be helpful. Great idea! I wouldn't be surprised if Thermo or Fisher sells these in a year or two. I had no idea things like this were already patented.

Needs a black-and-white film-grained scene of Ben, with an exaggerated expression of sad frustration, completely tangled up in the temp probe lead, as a a deep professional voice-over asks "How many times has this happened to you? Old-style temperature probes are awkward and inconvenient, but now there's STIR-BUDDY 9000!(tm)" ... " BUT WAIT. There's more! If you call within the next ..."

Casually drops one of the most innovative designs for lab equipment I’ve seen. Great work!

I'd pay whatever you wanted for this device. Seriously, I do TONS of chemistry and this would help me and solve so many problems! I'm drooling over this, man. Thank you for posting, but I am insanely jealous. Hahaha!

i love magnetic stiring, and this is the biggest tech advance in this field for the last 100 years of magnetic stiring history! Huge respect for opensourceing it

One thing, stir bars are absolutely notorious for picking up crud on their surface and causing all kinds of unanticipated reactions. If you work with sensitive chemistry, you often need to go through dozens of stir-bars within weeks. When I was working in a dirt-poor university lab, we actually just used paperclips pushed through molten glass. So it'd be interesting to think about changeable "shells" for smart stir-bars.

Excellent idea, and implemetation. As a frequent ex-user of stir bars in the lab, the size is a bit on the large side. We mostly used much smaller ones, so I think it must be possible to reduce the size quite a bit with some fiddling, to make it more practical. I do realize its a proof of concept though. Thumbs up!

Making tools is often just as interesting as what job you need the tool to accomplish.

Very nice concept, Ben. One of the chemical aspects I was immediately worried about though was chemical resistivity. Standard stir bars have teflon coating which is chemically inert but is sintered at high pressures and temperatures (above what would be considered suitable for electronics packaging). Virtually any other polymer is either not resistant to strong acids or bases, or to strong solvents, especially at elevated temperatures. I did not hear you say it in the video, but is that maybe one of the reasons why you did not pursue his as a product?

babe I can't come over, new applied science video just dropped

I wish I had some of those capabilities in MY lab stir bars years ago! ;-) I hope someone is able to produce these as an actual product in the future... great idea!

I just love you. Your videos are some of my favorite and you are a benevolent scientist, constantly giving back to the community.

I wish i could do apprentice ship in your lab, i love your work, the creative aspects, the reverse engineering, your projects are joy of science in purest disstilled form.

There are so many times in my work life when this world have been incredibly useful

Have to chuckle at the prominence/ubiquity of Digikey. They certainly have become the availability standard for electronic parts. I think I even used them back when I worked at Radio Shack after school.

this channel is so far beyond me - i took chemistry, physics and maths between 16 and 18, engineering after that. degree i never used. forgotten 9999%. stem still really interests me but its 30+ years. i love watching these videos, pretending to be a fly on the wall seeing all the now and how. wish i'd kept up... anyway. 👴😃

Beer brewing people will love this as well

A beaker with a captive stir bar sounds great, but would be a huge pain to clean.

Thank you for open sourcing this. This is an absolutely brilliant invention that I'm super surprised hasn't been invented yet.

I've just finished a multi stage programmable temp controller, wireless to an app, we're all at it. What you made here is brilliant! thanks for the upload most interesting and great idea/build

Really great work. Thanks for leaving it open source. That's a great gift to us all.

I've done some playing with RFID stuff - the drum core inductors work OK, but if you snap off the top, to make a T shape core, it works way better. I never found a source of ready-made coils like that, or custom ferrite.

We need more open source science equipment like this!

When you point out how awful the current temperature probe setup is, I found myself muttering amen brother. Very nice build. All the best to you. Thank you for sharing this

99/100 you make something that I have no use for or any prior interest in. For example, I'm not a chemist and I've never done any "real" chemistry outside of school. Yet I'll still watch this entire thing without feeling bored. Have you ever measured your IQ? It's gotta be off the charts, it's always amazing seeing the engineering and creativity in these projects.

That was a great breakdown of the modifications, and the top being clipped in is really good for thermal expansion, just floating on top.

this is really impressive, I can imagine that the precision you could possibly gain from this could speed up research significantly

You make great video's. Amazing to see you open source all your hard work. Truely inspirational.

I’m a simple man. I see a new Applied Science video, I hit like. Thank you!

Not quite the same, but I did see a pill-shaped gadget with its center of buoyancy and mass tuned in such a way that it would pivot as the density of the liquid changed. It had a little IC onboard that would use the angle of flotation as a proxy for liquid density around a very narrow range. Useful as a non-contact means of tracking how far along your beer fermenter is.

One of the coolest videos I've seen on your channel. And I've been watching your content for a loooooong time. Awesome job (:

This is so good its scary. How did no one come up with this yet? This is incredible.

this is much needed! I do wildlife rehabilitation and use a magnetic stirrer to mix the formula gently. thank you for thinking of this and sharing!

My God I would love to have this I've done so many reactions where I have to stir for 24 36 plus hours or more only to come back and find my stir bar bouncing around. This is very very very good idea

You make such amazing projects! Love your channel. I've been into optics lately and i was researching about building a DIY compound optical microscope (and maybe also implement some optical augmentation techniques like phase contrast, dark field/bright field, differential interference etc.). All i found on KZfaq and instructables was single lens (laser pointer/CD burner lens) basic microscopes, a concept I've already implemented a long time ago. I'd love to see you do anything in this direction because i feel like you're the best person to do it!

These are the sort of videos that I wish I could 'like' more than once. Brilliant stuff!

even though i'm not a chemist, i can clearly see how handy it would be. elegant solution!

Applied Science never will be replaced with GPT of any future versions. 💪

Thank you for open sourcing the idle IP. I wish to live in a world where we all do this.

That's what you call the innovation. Excellent idea.

You can get temp sensor RFID tags that are designed for implants. It's much smaller, and cheaper.

Ha! I remember you telling me about this idea so many years ago! So glad you built it :)

Looks like a fun project, thanks for sharing it with us Ben.

Cool idea, well tested, worked up, with many possible features.

Such an obvious product to make, kudos to you for figuring it out.

We used these bars pretty often and it’s not like putting a thermometer in there is a hassle but this just seems like a super cool concept lol

Very interesting. Another thought about the tx coil going between the mica heater and ceramic plate would be about thermal conduction properties. I imagine they made the heater have nearly the same XY area as the ceramic plate for maximum heat transfer. If the coil went between the heater and the ceramic plate, it would likely take more time to heat the fluid to its temperature. The coil would likely have to endure even more thermal punishment

Hey, that's my area of expertise! :D I've designed a few unusual and high-performance 134.2kHz HDX readers, to the point of having separate TX and RX amplifiers and even coils. Even though most were based around the same TMS3705 that you're using, I've managed to get a read range of more than half a meter. I know there's not a lot of info, but I volunteer to explain anything that I can. -Coil diameter: Assuming the RFID tag is a single point (valid assumption in this case), the ideal coil diameter for the best coupling would be about twice the range you're hoping for ( so that radius = distance from center) Larger coil puts wastes magnetic field energy in a large volume, and smaller coil keeps too much in one place. Magnetic fields fall down fairly abruptly because they are dipoles. -Input power: has to be (at least) enough to create a large enough magnetic field in a coil you're using. It could go very low with a superconducting coil, but hey, it's copper. If you use more copper, the power could go lower. Too much power can't hurt, but it can melt the coil or overload the power supply. -Coil inductance: not important by itself., but related to the input power and Q-factor. I've had many single-turn coil designs that could then be integrated into structures. Great for EMC! More important quality is the ESR of the coil. If your power budget is 1W, choose a coil such that the ESR@134kHz dissipates 1W at the voltage it's getting. If you need 10ohm ESR, and your Q factor is around 5, you need Measure the coil in-situ, because the nearby structures can add a lot of ESR (induction heating). -Tuning the coil: Beware of X7R capacitors! Ceramic capacitors (except NP0) are very nonlinear with voltage, and they're impossible to properly tune. Use film and/or NP0 capacitors instead. Also note that voltages can get to XXX Vpp. For good transmission, tune for the highest voltage when the coil is in its place. For good reception, and if your coil has a high Q-factor, tune for about 128.6kHz ( between the high and low bit frequencies of the FSK downlink) -Reading range: it can be limited by either TX or RX part. Put an air-core coil near the tag just as a probe to see when/if the tag sends the whole response back to the reader. If there is not enough power, the message from the tag to the reader doesn't get finished. If it gets finished and the reader doesn't receive it, you could work on the RX part. In your case, I'd bet that the SMPS nearby produces a LOT of magnetic noise that is picked up by the coil. they usually work at around 65kHz, which makes a harmonic right at the 130kHz where your RX part has to be the most sensitive. Test with a battery to compare. I recommend shielding the SMPS or using an old-school transformer.

Love this community you've cultivated over the years (nearly a decade?)

I've done some plant tissue culture, and having a temp and PH sensor in the stir bar would REALLY improve workflow on media prep.

For the heat resistant coil, you can coat the wire with high temperature paint from hardware store. Bake at 200°C for 30min and coil it up. Works good on custom heater cartridges up to 800°C.

NurdRage has a vid on replacing heating elements in hot plates, for hobbyists doing everything they can to keep down lab costs.

You are awesome. Cool invention and a great explanation how everything works.

This is such a good idea, you could literally halve the size of that stir bar if you worked with the chipset manufacturer to wire bond the chips directly to a much smaller and thinner PCB that way it would be quite easy to get this to normal stir bar dimensions. For a prototype its pretty good.

I'm surprised that: 1. This is not already a existing product, it's super useful for lab work 2. You are giving all these out for free!!!

I read the title and said “holy shit” out loud. This is an AMAZING idea!!!

You're a genius and you've taught me so many things thank you!

Excellent implementation, you can improve the range of this stuff by placing ferrite sheet between the coil and the stir bar which dramatically drops the temperature it's exposed to. They can charge cars at about 30-40cm so there's a lot of scope there. Thanks for the pointer on the ceramic coated wire, that has a lot options for me on other projects.

"I was pretty proud of that" yeah, you should be! Great video as usual, it’s always a good day when you upload. Thanks!

"I guess it want that hard to reverse engineer" .....says Ben. Guy builds his own x-ray machine, magnetic resonance whatsit, mass spec, and still drops that humble bomb on us with a little giggle. Damn it Ben, stop being awesome! .....No, dont stop being awesome. Really cool work, mate. Id love to see this idea picked up and the maker crowd come out with neat chem equipment. My first toe dipping into chem techniques was distilling ethanol out of cheap booze in glassware that had rubber stoppers. Had to modify a bung for 3 holes, one for the bubble elbow, one for the mercury thermometer, and one for a long stem funnel for adding more booze. Didnt have a pump for the condenser jacket so I set up a pair of buckets (one on the table, the other on a chair) to run as a siphon, when one ran out, swap em around and start the siphon again. The next run I did was homemade HCl via the Mannheim reaction (IIRC, its the sodium bisulfate + table salt one) since we had some old pool chemicals laying around. That was the night I discovered what a lovely shade of "DO NOT BREATH THIS" yellow-green death chlorine gas is (yes, I had ventilation, still it was an interesting experience. Pucker factor 7 event). Ended up being the first glass lampwork I did too, made a U bend tube from some narrow tube straights for a double flask backflow rig to catch the suckback at the end of the reaction. Learning experience 10/10, would do again. Risk level 4/10 would not let my kids do that unsupervised (like I was 🤣 But at least I wouldnt accuse them of making drugs just because there is a white crystalline mass left over in the reaction vessel.....like I was 😒 Do you know how hard it is to explain a reaction and the resultant compounds to someone who thinks "ermuhgurd laboratory glassware cops gonna kick our doors down" ......Its quite annoying to say the least......) Anyhoo, Ben, youre a paragon in the garage scientist world. Dont ever stop being awesome. And thanks for the content! Your work does not go unappreciated round these parts 😉

I’m a high school chemistry teacher. This is ingenious! I would love to learn more.

I don't even have to watch this to know I'm in for another awesome project.

This is awesome and you are awesome for open sourcing it. The only downside I see is the dev board doesn't seem to be available anymore, and the TMS37157 themself are end of life.

This is such an amazing project and could seriously reduce fires in a lab from unattended experiments.

This is awesome! If you setup a store and have a third party manufacturer produce the stir bars and hot plate, you would make a decent sum but more importantly would make this accessible.

Omg I would buy this right now... I have a habit of putting 2 beakers on the hotplate when I need hot solvent, but I could just use a different stir bar. This is amazing

Love seeing the NileRed beaker pop up on so many channels

this is truly useful equipment to have in a lab, for sure it has potential for marketing

It's cool that there is a way to make this work at all.

The inductor as the coil is genius!

That's clever, thanks for publishing!

Please when this is available to buy somewhere let us know. This is an epic idea. Soooo much better than using a probe. I hope some kits can be produced for some popular stir hotplates.

Really nice, tidy project! 👌

Egads man, you're always doing the coolest things.

Brilliant as always! Thanks for sharing!

As always that was super interesting, Ben. 👍

That was indeed interesting, but I have a quick tip for those wanting to measure temperature without anything inside the flask. Try an IR thermometer. They are under $20 and typically read within 5C or less of error of what the actual temperature inside the flask is. Usually you can just aim it near the bottom/middle where there is still lots of liquid inside, but not so close to the bottom that it picks up the heating element. This is not better than what AS is suggesting, but it is quick, cheap and "off the shelf", and you probably already have an IR thermometer or two.

You continue to amaze us...🤩

I will craft this to benefit my synthesis work Thank you very much

I'm wondering if it's possible to create a thin mat on the outside of the ceramic that contains the coil, allowing you to use the device without having to modify the stir plate. Essentially, it's an add-on that you can use on any existing plate.

This is excellent, thank you for making it public.

Just a thought... First of all, excellent stuff as always. If the temp sensor is in direct communication at all times, it could be better to just use an on/off heating scheme depending on the energy to mass ratio. I say this because we once developed an induction heating process (instant on/off with very high energy to thermal mass ratio) that used a laser temp sensor input and our pic controller simply turned on the power until the object/liquid was at temperature. In this way, the feedback was instantaneous and as precise (even with an offset) as possible...much faster and more accurate than a PID. It was even more energy efficient because the calculation time was very close to zero. We used a 1Kw induction power supply to heat a small (25mm^2) susceptor to 300C in less than a second with less than a degree of overshoot....and held it there indefinitely.

That’s a genius idea! Thanks for sharing.

Seems like such a good idea, I would have liked more about why your group decided not further pursue commercializing it.

How is this not already a thing??? But bravo, this needs to exisy

Brilliant! Incidentally, Ive started creating a diy temperature controller as well. But that one for soldering low-temperature solder paste (and without RFID, but could add it later too now that Im seeing this haha!). For that I will need to be able to generate a very strict temperature profile, just like you can with your kiln, and I have been thinking about using a peltier device, lt8722 and a pot of hot water.

Thanks. You just gave me a few new ideas. Just not about a stir plate.

This is a very interesting concept. Something to consider if attempting to use this at higher temperatures is the change in impedance of your coil altering the tuning. I'm not great with RF and only experienced with 13.56MHz so this may be a non issue.

Awesome idea and like always definitely interesting 🤔!

Next level genius! Awesome work

I sure hope that you patented this concept. This is very saleable product.

Nice project as always!

Even without a fancy stir bar, an RFID sticker on the flask could be useful. Use the tag for inventor management or process control.

Unbelievably fascinating. Invention for invention's sake (like research for research sake).