So I’ve been back from holidays for about 2 weeks now, what do I have to show for this? Well, to be honest, not as much as I’d hoped. I’ve actually been struggling with a little bit of mild anxiety. This all started sometime while I was in Europe on vacation. I didn’t know it at the time, but it turns out Nasonex (a nasal steroid for allergies), has some side effects that actually affect me. Anxiety is not something I have ever really had. So it caught me off guard.

I’ve stopped using the spray for about 2 weeks now and the anxiety is almost completely gone. It only pops up if I don’t sleep enough now. This made me a little more aware of what people who suffer from anxiety feel. It’s not fun. It makes you doubt even your own rational thoughts. My anxiety was actually centered around “being stuck somewhere” … like planes, or even a restaurant. Anytime that I would be forced to not move, whether because of norms (like at a restaurant or movie theater), or in a plane or bus, my hands would sweat, and if I thought too much I would actually get a full on panic attack where my chest would feel warm and my heart would beat faster. I managed to keep it under control though.

Either way, it’s mostly gone now and I’ve actually continued working on the DropBOB PRO cold brew machine a little more. I’ve increased the fan from a 30mm to a 35mm (this doesn’t sound like a lot, but it actually doubles the flow). I’ve also changed the heat sink from 7.5mm thick to 12.5mm thick (this also almost doubles the heat transfer).


When my valve is at the coldest temperature (about 23C when the ambient is 27C), the heat sink is typically around 40-45C. This means that there is about 20C between the cold & the hot side. If I can lower the hot side by a few degrees, this should lower the temp of the cold side as well. With an ambient temp of about 27C compared to hot of about 45C this only gives me about 18C of optimization … So if I can get even half of that, I should be able to get cold temps of around 15-19C which is right where I want it.


The good news is that I’ve been able to add these small upgrades without losing the ability to go back to the smaller fan & sink. I’m building into the model some adjustability. I can have a smaller fan for a mini model … or large fan for pro model. I also added an extreme option where I can stack 2 peltier plates and see if I can supercharge my temperature control for those who want to really cool or really heat the water. Double hardware should double my range right? maybe I can do 0C to 100C … and then we’d have like a super machine that can do cold brew & hot brew & everything in between. And this would be super precise too! probably within a couple degrees.

I’ve ordered this new model to come in soon, probably in the next week or so: New housing from 3dhubs, New electronics from Digikey & New board from OshPark.

I’ve also updated the PRO model (remember the triple tower thing?). Well, I figure some of you may want it in just a single. So I’ve updated it into a single, but still with all the PRO features! Pricing & availability still to come. I’m currently working on putting together a nice little rendered video showing this new “Hit single” model in all of its digital detail! so stay tuned!