Category Archives: #concept

DropBOB commissioned project – Pyramid Head – Approval Drawings


So I’ve been busy working on finishing the Model and coming up with a good set of Approvals/Layouts for my commissioned Pyramid Head Cosplay. It’s been a real hit on my Etsy Page.
I’m not quite happy with these yet, but it’s a start. I often berate the drafters at my “other job” for having terrible drawings … but making drawings from scratch is hard. Especially when the information you want to convey/receive is not fully defined yet.

Continue reading DropBOB commissioned project – Pyramid Head – Approval Drawings

DropBOB Designs: learning a new skill!


So I’ve been wanting to do this for a few years now, but I’ve never had the patience to really devote some time to it … Until now.

Rendering of partially designed board (top view)

I’ve been learning circuit board design and component selection. I’m hoping to not only simplify the entire wiring design for my cold brewer. I’m trying to expand its capabilities tenfold.

Continue reading DropBOB Designs: learning a new skill!

DropBOB PRO – Preliminary design update


Some of you may be wondering what I’ve been up to over the last little while. I haven’t posted anything, nor have I put my “Star-Lord” Costume up for sale. Well, it’s because something has been bugging me. I’m unsettled about one of my designs … and its preventing me from focusing on other things. 

As you can see from the above image, I’m working on a PRO version (i.e something you’d see in a coffeeshop or a coffee enthusiast kitchen). All, while improving on the DropBOB control mechanism.

You see I’m no longer just happy with having the most accurate and flexible cold brewing drop control on the market. I want more! … I’ve added temperature control as well now. With a little bit of testing, I’d like to not only be able to have my drops colder, but also hotter, all at the slide of a finger on your smartphone.
I’ve also added a second photo-interrupter for a drop anticipation feature. And I’m getting rid of the Long neck that hung below the water (that was a standard plumbing parts restriction) … I’m also designing my own valve … And making the glass custom. Oh, and making dishwasher friendly.
Ya, I know … this is ambitious. Here’s to 2017 being the year “DropBOB Designs” takes off. I hope.
Cheers,
-D.B.

Closed loop drop-BOB: the only cold drip coffee maker you can count on!


So I’ve completed my design. I’ve converted my 3d printable files to STL files and have sent them off to the printer: www.3dhubs.com. fingers crossed that everything comes back nice … you never know with these types of “compact” housings… Plus this is my first functional 3d print … Everything else I’ve done in the past was not as critical.

With this initial beta release, I can control my coffee maker from anywhere. I can check the progress of how it is doing. and I can adjust the flavor profile depending on how many drops per minute (DPM) & grind type I use. And I can know that it is always exactly where I want it because it’s a closed loop system with constant feedback.

Features:

  •  real-time drip-rate monitoring
  •  drip rate selection using micro servo
  •  fully functional wifi-enabled controller (hackable arduino) files shared on Github … 
  •  LiPO 850mAh battery for anywhere brewing
  •  5VDC battery charger (micro-USB same as your phone)
  •  fully customizable monitoring display (it’s your phone) Server & app run by Blynk
  •  use any of your favorite glasses or mugs.
  •  industrial pipe design
  • (planned feature) ETA
  • (planned feature) battery monitor

Drop-BOB – a better coffee maker – Cold Drip


I’ve been working on my software today. I think I have a good base that I will call this version V0.1 … an alpha release, since I know there are a few crashes and more bugs than I would allow in my beta software.
But overall, I’m happy with the result. I have my Arduino code working well with the Blynk platform. From top to bottom & left to right I can: 

  – monitor network connection
  – visually see the servo position
  – monitor up-time
  – see the real time DPM (drops per minute)
  – automatically tweet about making Coffee
  – see the desired drip rate (Set-point)
  – count drops
  – see a history of DPM
  – modify desired drip rate (set-point)
  – Manually adjust the servo position
  – restart when finished
  – simulate a drop
  – and pause the system
All while using a smaller package than when I was using an arduino with an LCD … remember that?
The next step right now is to CAD this “THING” (that’s the real name) … And then place it nicely into my drop-BOB (3d printed design to hold all these components) … It counts drops … and it just bob’s under the water holding thing … kinda sounds cute.

Oh, and also, since my idea is to eventually release this into the world with huge potential for modifications and improvements, I’ve shared my code on my GitHUB. Feel free to make improvements. make comments, or even suggestions that I can implement (note, I’m not a software guy … I juts do this for fun. So go easy on my code).

Hack-on!

Closed Loop Drop-BOB … The Cold Drip Coffee maker that could!


So its been longer than I’d have hoped for this post, but I was so torn in my design ideas that I decided to wait a little. I let the ideas settle in my mind and eventually, the inspiration came!

I had a few design criteria to make this Cold Drip coffee maker:

  • Simple & Elegant
  • Easy to manufacture with many “off the shelf” components
  • Hack-able
  • Not offensive to Jenn’s Eye (The wife) … so It can be kept in the kitchen
  • Has a certain “Bobby Style
  • Not too expensive (I’ll probably optimize this later) 
The worst part is that I did not want to settle on any of these criteria … none more important than the other, but all required.
Cold Drip Coffee Maker – “Closed Loop Drop-BOB V1.0” (**Name is a work in progress)
Let me remind you of the progression of the designs prior to V1.0:
V0.1 – the proof of concept
V0.2 – functional prototype
V0.5 – New and improved looks

And now, just recently out of the Alpha stage and graduating to the Beta testing stage: The V1.0 – “Closed loop Drop-BOB” (Name is a work in progress) … The model is not fully manufactured yet (still a few parts on order & to order at the moment). But here is what I’ve got so far:
It all started with the simple wooden bracket shown above. Even though this is not what I want for the final V1.0 product, It helped me visualize what I actually want.

Once I made the bracket, I quickly drilled and taped the brass plug and attached it. Oh, I skipped the part where I cut glass … I’ll come back to that.
This is the part that actually gave me a kick in the ass to make this thing. Since I took apart my original prototype, I’ve been drinking peasant coffee (you know from an espresso maker, like the rest of the world)… After tasting this liquid nectar from the slow drip process, I was all hyped up and wanted to finish this new and improved version.

 It was so good to see this familiar coffee colour (Canadian spelling eh). And since I started making smaller batches, I was able to minimize waste. It takes the same amount of grounds to make 2 shots of extra delicious cold drip, as it does to make 2 shots from an espresso maker … This is for those who think Cold Drip costs more on grounds … not necessarily.

 So back to the glass cutting part. This is the part of the design that forced me to re-think my ways … At first I wanted to make my own water reservoir because I couldn’t find anything on the market that would work with a drip valve (open at the bottom & the top). I also wanted to potentially control the temperature with a peltier plate … but that will be for a later version.

I eventually came to the conclusion that I should modify a container to suit my purpose. Diamond tip glass cutting bits are a little expensive (but who am I kidding … I love buy new tools).

I did the entire cut on my drill press, with the glass inside another glass filled with water. Make sure you have no air bubbles.

The hole came out nice. Only a few little chips were missing, but nothing I can’t deal with by using some washers and O-rings.

This part was the most tricky … and the reason I spent over a hour standing in front of the brass fittings part of the local hope depot store.

Turns out that compression fittings are not easy to combine with other types of fitting .. like MIP, and Pipe treads, etc … I needed some distance between my valve and the glass ,so I can add my little beauty of a “Close Loop” servo control box (more on this later) … You see, the next great idea I had was not to connect anything other than a single hole to the bottom of a glass (or, steel, or wood, or coconut, etc). This allows me to use virtually any container that I can make a 3/8″ hole at the bottom.

Seems to work nice. Got the distance I was looking for by connecting the 1/8″ compression thread valve to a flared copper pipe, to a female MIP, to a 3/8″ OD short brass pipe and connected all that with some O-rings to prevent leakage … I feel like I can optimize this later for cost and simplicity, but good enough for V1.0.
Here’s where all the magic happens. This little box is less than 2 square inches … And packs the servo, the valve, and the photo-interrupter all in a tiny little robust package. (The wireless controller ESP8266 will also be fit into here shortly … if it ever arrives)
Once this think is fully built, I should be able to control and monitor the drip rate from my smart phone … from anywhere in the world!

Cold Drip Coffee Maker – New & Improved looks


Just a quick update. Not much to it, I had to tear the old design apart to take some steel I need to use for the side tables. But I really missed my cold coffee. So I gave it a much needed re-design. Now its much more compact & simple.

 Next step will be to upgrade the soda bottle to a glass bottle … but for me to do that, I’ll need a few new tools:

 – Glass scoring bit mounted to score a bottle around its base
 – diamond dremel bit … to drill small holes in glass

I may also work on a 3d printed structure to hold the servo & photo-interupter.

For now, I look forward to cold drip coffee tomorrow with the famillia. Happy family day.

Cold Drip Coffee Extraction – Idea & Proof of concept


So I’ve been wanting to make a cold drip coffee machine for a long time now. I got hooked when I first tried it at Parallel 49 Coffee Shop.

So as my list of tasks for the week dwindled (now complete, save for side tables), I started my cold brew design with a good old trip to home depot (just to see what they have). It turns out that they have pretty much everything I needed to get started on my proof of concept.

Now, I know this “cold coffee” shit has been done many times. So why a proof of concept? Well from what I read online, Its an “unstable design”. You can’t really get the dripping just right … and even when you do … an hour later, it will be either no longer dripping, or dripping too fast.

So, I decided to start with the basics. Here is my home depot parts list:

1x wine bottle (from home)
1x carafe (from home)
Here’s what it looks like all setup:

Now, lessons learned. Since the wine bottle at the top does not let air back in, the air must come up from the tube … which it does, but not as predictably as I’d hoped. The result is an erratic drip, that needs to be adjusted every few hours. At the end I opened up both valves all the way … it still only dripped a little due to the back flow of air.

So I don’t like the original design … even though it made great coffee.

So today, I took apart an old Halloween Costume from 2011 to make my second “more commonly seen” version of the cold drip coffee maker.

I mostly just wanted to test out a system with no back-flow of air and I wanted to see the adjust-ability and repeat-ability of the 1/4″ needle valve.

So far, I’ve tried as slow as 11 drops/min and it stopped functioning after about 1-hr … (sticktion maybe?) So, I’ve increased it to about 40 dpm.

What I am working towards is a design that I can accurately control the flow (needle valve or Solenoid valve? … maybe even servo controlled needle valve). I’ve toyed with the idea of using a servo controlled valve but I think that would be too noisy.

I’m leaning towards a closed loop servo controlled needle valve (via arduino) with piezo electric drop detection (via sound). This has not yet been attempted by the internet (by my searching).

Once I can get this part working I will try to also control the pressure & oxygen content using NO2 cartridges. Not sure how I would fabricate a container for that though … food for thought.