Mug and TeaHi everyone. I wanted to write to you all about a project a very good friend of mine, Dean Verhoeven, has been working on for the last 10 years that I thought folks would like. Over that time, he has been perfecting the design and setting up production of a stainless steel mug, Temperfect, that holds a person’s coffee or tea at just the right temperature for hours – without any external input.

Basically, you pour your too-hot-to-drink beverage into the cup. A layer of non-toxic wax trapped inside between the stainless steel walls absorbs the extra heat from the liquid bringing it down to just the right temperature in only a few minutes. Over the next few hours, that extra heat is released back into the liquid thereby holding it at a nice toasty temperature. No more too hot or too cold liquids!

I don’t know about you, but when it comes to other stainless steel mugs, I’ve always had an issue with my tea going cold before I’d get half way through it. I tend to hyper-focus when I’m working so it may be 30 minutes before the next few sips. I’m not that fussy when it comes to my palette but having to drink cold tea just isn’t doable – even for me. In addition, my tongue is particularly sensitive to heat so I end up having to wait for my drink to cool. Hot drinks that my wife guzzles down with glee leave me with burns that take days to heal. With the Temperfect mug, I can start drinking my tea right away and it stays nice and toasty for hours.

Lifelong Friends

Motorcycle Trip

Given that Dean and I have been good friends since elementary school, I have an insiders take on the man who invented the Temperfect mug by Joeveo. That’s decades of shared and treasured friendship. I still remember as pre-teens sitting behind him on his old Yamaha motorcycle and hanging on for dear life as we raced down an old deserted road. Racing along and watching as the speedometer would slowly creep higher in our attempt to break our latest speed record was excruciatingly fun at that young age.

Part of the thrill involved mustering up enough courage to keep the gas wide open even in the face of the rapidly approaching steel guardrail at the end of the road. Just a few more seconds, and then just a few more on top of that, as our eyes were glued to the speedo waiting for the needle to reach a new high before the wall of steel drew too close. At the last moment, whoever was driving would mash down hard on the brakes to avoid a collision. Based upon how close we’d come to hitting the guardrail informed the next go-around. Yeah, I never told my Mom what we were up to.

Later, we were roomies during the first two years in college. Dean went on to get a PhD in physics and I studied engineering and ended up with a degree in mathematics. Over the decades, I morphed into a house builder and he started doing what he loves most, inventing.

Take it from someone that’s known Dean ever since elementary school, if Dean is anything, it’s patient and methodical, along with just really smart. He’s worked on refining the Temperfect mug for over a decade because he wanted it to be perfect. Whereas, I tend to spend just enough time on a subject and then jump in; he’ll study all the ins-and-outs, have a well thought out plan, and then execute, record data, and refine. If you’ve read some of this website, I’m guessing you have a sense for the effort I put into my work. So when I say that Dean is even more focused and careful in his efforts, I’m guessing you can get a sense for the depth, precision, and care he has built into the Temperfect mug.

Unique Design

Mug Cutaway

Setting the fond memories aside, his mug is finally a reality and I, of course, promised to help try to get the word out. I say “of course” because he’s such a dear friend. However, the cool fact of the matter is that the mug really does something that no other mug does – drops too-hot-to-drink liquid down to a pleasantly toasty temperature in a couple of minutes and then keeps it there for hours. Sure, they are starting to make mugs that sit on electrical coasters that have a heating element embedded inside, but I’m not particularly keen on bathing the liquids I drink in EMF fields – see Electromagnetic Fields Explained and Water Structure. I’m even more leery of models that have a battery inside to keep the liquid warm when you’re on the go. What if the battery leaks or worse?

The Temperfect mug doesn’t have any of those issues. There are no “moving parts”. Instead, it uses a non-toxic wax carefully selected for its melting point that is sandwiched between two of the three stainless steel walls in the mug. The wax is safe enough that you could eat it without ill effect. Although, I doubt that it’d be very tasty. I remember Dean spending a long, long time looking for just that right wax with the correct properties that was also non-toxic.

Said another way, the mug has the typical vacuum layer trapped between the two outer walls for insulation. However, it has a third inner stainless steel wall that creates the space for the wax. The outer layer holds the vacuum, and the inner layer holds the wax. This is the only triple wall mug that I know of.

When you pour really hot liquid into the cup, the excess heat is quickly transferred into the wax layer via a web of copper fins embedded in the wax that makes contact with the inner shell holding the hot liquid. This excess heat is absorbed by the wax and causes it to melt. Over the next three hours, the wax slowly cools and re-solidifies. As it does, it gives back the excess heat it stored up and thereby holds the liquid at a constant 120-140 degrees Fahrenheit (50-60C). There are no moving parts, no electric fields, no batteries, nothing to break. It’s just really cool engineering.

In case you’re interested, I’ve included temperature graphs comparing the Temperfect mug to other types. You can also review the testimonies of others on the KickStarter Campaign.

Temperature Ahhh Zone

Temperature Graph

Plastic Lid Hazards

Mug Lid Parts

We all know about the hazards of plastic. Most plastics contain chemicals that mimic the hormone called estrogen; most plastics contain “xenoestrogens”. Xenoestrogens cause symptoms in both men and women that includes weight gain, insomnia, moodiness, fatigue, allergies, and more – Ditch the Plastic, It Is Making You Sad, Fat, and Infertile.

Great care has been taken in selecting the Polypropylene (PP) lid on the Temperfect mug. When I asked Dean about the safety of this plastic he wrote, “My notes on estrogenic activity of leachates from different resins are below, with links to articles. The upshot is that PP is one of the few resins where it is pretty much agreed that it does not leach estrogen mimicking compounds.”

So unlike other mugs where a person doesn’t have a clue whether the lid is loaded up with xenoestrogens like BPA that mimic natural estrogen and mess up a person’s hormones, care has be taken to select a safe plastic. This includes avoiding the questionable “non-BPA” plastic called Tritan that was introduced as a supposed safe alternative to BPA – not.

The one issue that cropped up with the safe Polypropylene (PP) lids is that they can warp over a period of time when exposed to really hot liquid. In fact, a small percentage of the first group of customers found that their lids didn’t seal well over time. Soon after, the reason for the leaking was discovered and fixed.

Dean has told me that one solution for a misshaped lid is to simple drop the lid in boiling water for a few minutes and then set it out to cool. The lid will naturally revert back to its flat shape. Thankfully, all new mugs come with a re-designed silicone seal that can deal with the slight warping that can occur and thereby saves a person from ever having to boil their lids. So no more leaks.

Note: While the issues with the lid sealing to the mug body have been solved, the one-finger shutter opening on the lid itself was not designed for those people that carry their mugs laying on their side in a handbag or backpack. It is not water-tight. Dean is working on making a water-tight lid but it’s currently not available.

Support Small Business

Dean China Factory

Being from the U.S.A., it would have been nice if Dean could have found a manufacturer here in the “States”. Unfortunately, mug forming work is now being done in China. In large part, we have NAFTA and GAFT to thank for this – U.S. Economy Lost Nearly 700,000 Jobs Because of NAFTA.

It was a real saga getting the mug body produced overseas. Dean and I would talk over the phone about the difficulty in getting the triple wall mugs produced to Dean’s high standards. The issues ranged from just trying to get on the production schedule, to poorly maintained machinery, to more exacerbating issues like discovering the small spot of solder used on the copper fins inside the mug vaporized under the high heat in the tempering ovens causing the mugs to blow up like balloons. Wow.

Having lived and worked overseas myself, the challenges in getting work done are often of a variety and number that one would not otherwise expect. It’s hard enough launching a new product in a country where language and culture are familiar. It’s a testament to Dean’s commitment to quality that he persevered for over a year before finally getting mug bodies produced to his high standards. If you’re interested, you can read more about those challenges under Comments on the KickStarter Campaign.

Well Worth the Price


At $40 a mug, the price is about double that of a decent vacuum insulated mug. That being said, for the extra $20, you get a mug that has been designed with great care and will keep your hot liquids at the perfect drinking temperature for hours with no fuss. It’s a “no-brainer” for folks like me that have sensitive tongues and often forget about their drink for longer periods of time.

Well, with my Temperfect mug in hand, I’ll say adieu. I’m off to go mix up some loose leaf peppermint tea along with licorice root for my adrenals. By the way, for those that are like me and just don’t have an aptitude for cooking, even if it’s only brewing up a cup of tea, I’ve found that tea infusers that hold a lot of loose leaf, rest right on the cup, and have a lid that doubles as a dish to hold the strainer when you take it out work best. I like being able to drop in the strainer, return to computer coding, and then set the strainer in the overturned lid after brewing is finished without having to get up a second time.

Thank goodness my wife takes some pleasure in cooking. Otherwise, I’d really be lost. Cheers.

get one!


Temperfect Mug Giveaway!

Sleeve Colors

Dean has generously donated three mugs to be given away to the moldy community. I’ll be giving away one free mug with each of the next three articles I post. In the meantime, it would be awesome if folks would help support this small-business endeavor. As many of you know, I don’t “do” social media so it would be awesome if others posted links to Joeveo. Note: I don’t have any financial affiliation.


  • Nancy from Maryland is the July 2018 Temperfect Mug Giveaway winner. She writes, “I’m in the middle of healing from CIRS and this definitely brightens my day – the timing is spot-on.” Congratulations Nancy and better luck next time to everyone else that signed up.
  • Charlie from Washington is the October 2018 Temperfect Mug Giveaway winnder. He writes, Your detailed and thorough blog may well have saved my life. After years of searching for the cause of my suffering I found my way to this blog and I am now recovering well and indebted to you! As an aerospace engineer in Seattle, I am impressed with the technology in this mug. I really appreciate this and look forward to putting it to good use! Congratulations Charlie and better luck next time to everyone else.