Top 5 specifications, top 5 constraints

The goal for my design project is to create a more complete version of my prototype cooler fan. I built the prototype last year and only focused on the functionality, and this time around I am trying to create a more “finished” product. The fan is rather simple, just a water pump cycling cold water through a heat exchanger, and a fan blowing air through the exchanger. Each component is laying around and wires are hanging everywhere, and I want to tidy it up. 

The main thing I want to address is creating a finished material look. I plan on 3D printing the main housing, and plan to either sand it down and/or epoxy the exterior. I am aware that 3D printing isn’t the best manufacturing method, but it is what’s available to me. 3D printing also lets me design more intricate shapes I couldn’t make by hand. 

Another thing I want to do is to add controls for the pump and fan speed. Currently, I have no way to adjust these settings, but with this version I would like to add switches. I am not too concerned with the electronics, as it’s relatively simple with an arduino. Since I’m adding an arduino for this function, I also decided to add a temperature sensor to measure the water temperature. 

Part of adding switches is finding one I like. I have been shopping around online for minimalistic components, but no luck so far. I’d rather not use standard toggle switches and momentary switches, as they look too basic for me. 

The aesthetic is another feature I want to make sure I get right. I am aiming for a minimalistic and rugged look. I like the simplicity of minimalism and I wanted to combine that with the outdoorsy look of camping gear. However the current design kind of looks too simple? The housing was designed using simple shapes and as little features as possible, so it will either look minimalistic or plain. 

A feature that I would like, but I think is a little ambitious right now is to have the fan portion rotate to change to angle. Currently, my design has the fan in a static position, blowing air straight horizontally. But if I have time, I would like to add some sort of friction hinge to rotate the fan. 

The top constraint in this project is finding tools to work with. I originally planned on working with aluminum at the metal shop on campus. When I went to the shop with my initial plans (a LED pod lights for offroading) I was essentially turned away because I was going to waste their time with this project. With this constraint, I decided to not work with anything that needs campus assistance. This was solved by completing changing my project to something I can 3D print.

Another constraint is my electrical skills as I have very minimal knowledge creating my own schematics. I designed a pretty simple circuit for power, speed, and temperature, but I’m not 100% sure it will work. 

The 3D printer I am using, an Ender 3, has a small build plate for the print I am aiming for. I didn’t think about this issue when initially designing the housing, but when I was test printing I ran into not having enough print space. I think I am going to work around this by printing the housing in 3 main sections: the threaded cap, top, and exchanger housing. For the final print, I am hoping to use the printers on campus with higher print definition and bigger print bed. 

Printing the threads for the cap to the cooler is another issue I’ve run into. My printer is having issues printing the actual thread, which I believe is due to overhang and too low print quality. I have been reverse engineering the thread dimensions, but I cannot check the fitment due to the threads not printing correctly. I do believe I have relatively accurate enough measurements, but I’d like to dial it in more. 

One final constraint I am running into are new ideas. I am trying to add elements of minimalism and just finer details to the project, but I am at a stand still. I have been trying different versions, but I can’t seem to make progress on this part. This concern isn’t a significant problem because I do have a designed project, but I would like to improve on this aspect.