Window Sill Shelf

TL;DR: It gets hot in SoCal so I overengineered a shelf to hold a fan to blow cool air into our bedroom at night.

Just a quick post this time—I decided to put my printer to work making another functional print! SoCal is a desert, so it gets very hot during the day, but cooler at night. A few days this past week were especially brutal. To help circulate the air at night, we use a little Vornado fan, but its effectiveness wanes when it doesn’t have access to cooler air.

A simple, but effective design. I originally intended to print the shelf itself too, but I found a piece of wood that I’ll cut later to eliminate the use of this piece of cardboard, haha.

I designed a very simple shelf comprised of brackets, a brace, and the shelf itself. I sized the brackets specifically for our bedroom windowsill. There is a very satisfying click during installation, but the shelf is very easily removable in case we need to close the window.

I didn’t end up printing the shelf part because I found a piece of spare wood which will work perfectly, and I installed a piece of cardboard until I find time to cut it. Although this specific design isn’t super generalizable, I decided to upload it to thingiverse anyway in case anybody is inspired to made minor modifications to fit their needs:

Stay safe and healthy!

#BlackLivesMatter Gear

TL;DR: I believe #BlackLivesMatter. I still can’t say anything more eloquently than what has been said by others elsewhere, so I’m going to chip into the cause in my own way. If you’ve donated to a reputable social justice charity, I’m more than happy to send you some 3D Printed #earsavers or touch-free door openers.

Despite law enforcement agencies across the country telegraphing they don’t believe so, black lives do matter. To help the cause in a small way, I designed a new earsaver and a touch-free door opener/keypad stylus.

The earsaver is a modified version of the NIH-approved design found here: No critical outside dimensions were altered, and the part remains very flexible. Earsavers are very useful for anybody who needs to wear a mask (aka EVERYBODY WHO LEAVES THEIR HOME). You put this on the back of your head and hook your mask straps around it instead of around your ears. This takes the pressure off your ears and makes wearing the mask much more tolerable.

I modified an NIH-approved design to allow wearers to show solidarity with the movement.

Creating the door opener/stylus was a bit more involved; I created the design from scratch, using a few existing designs as inspiration. The hook is useful for opening door handles without touching the surfaces. A strip of copper tape wrapped around the fist allows the stylus to function on capacitive touch screens, as long as you touch the bottom of the strip with your thumb. This is useful for pressing buttons at the self-checkout line in grocery stores.

This touch-free door opener doubles as a stylus useful for hitting capacitive-touch buttons at self-checkouts. The strip of copper tape is the secret-sauce which allows this functionality.

If you’d like some of these doodads, I’m happy to send them to you free of charge. Since I literally finalized the design at lunch today, I don’t have a huge stockpile right now. For now, I’m going to prioritize those who have donated to reputable social justice related charities, but I aim to eventually provide these for anybody who wants them, so feel free to reach out!

COVID: Endgame

TL;DR: Since the acute need for PPE has diminished, I am no longer producing parts on regular basis. However, I do have a reserve of face shields and earsavers remaining, and am more than happy to ramp up production if you or anybody you know need equipment.

Over the past 8 weeks, I personally manufactured about 1000 face shields and 1000 ear savers on my two 3D printers, delivering a quantity of about 880 of each to healthcare friends and friends of friends in places all over the country including: LA, SF, OC, Oakland, Tennessee, Oregon, South Carolina, Georgia, and New York. Furthermore, two local groups I work with have distributed over 75,000 and 22,000 face shields and other units of PPE, respectively.

However, it appears that more and more hospitals are getting their supply chains back in order, and the shortfalls do not seem as desperate as they were a few weeks ago.

This is what ~50 lbs of empty filament spools looks like

I feel this was a huge accomplishment, and I could not have done it without the support of everybody who chipped in for expenses—it was incredibly generous of you. I plan to donate the remaining funds to the charity Good360 in a few weeks if the need remains low and seems unlikely to ramp up in the short-to-medium term.

I hope everybody has a wonderful Memorial Day Weekend, and stays as happy and healthy as possible. I sincerely hope enough of us remain vigilant and change our habits enough to ensure the gains and sacrifices we’ve made the past few weeks are not wasted. I pray that the worst of this situation is truly over for us. However, if there’s one silver lining to this, I know that if the need for more PPE arises again, we’ll be able to ramp back up much faster next time.

Quick update — now with earsavers!

TL;DR: In addition to face shields, I’m now producing NIH-approved earsavers. Let me know if you need some!

About two weeks ago, I upgraded my old cloggy 0.4mm nozzle to a great 0.8mm nozzle courtesy of Micro Swiss ( Making this switch greatly increased my printing capacity—when you go from a smaller nozzle to a larger one, the volume of material you can deposit increases by r^2–you reduce both the travel count within each layer, and increase the layer height at which you can print at. This leads to a huge boost in printing speed, with the drawback of losing details. However, for what I’m mass-producing right now, loss in detail is a very minor concern, so cutting my print time nearly in half on one printer is well worth the trade off.

While I continue manufacturing and delivering NIH-approved face shields on one printer, I’ve dedicated my other to the production of NIH-approved earsavers ( for the next week or two. These popular devices are great for relieving pressure off the ears of healthcare workers who need to wear surgical masks for hours on end during their shifts. By the end of this week, I will have delivered over 350 of them (including shipments to South Carolina, Tennessee, Oregon, and NorCal!)

Here’s a snapshot of my life for the past few weeks:

Left: 75x frames and 260x earsavers ready to be delivered this weekend
Right-Top: I’ve chewed through quite a bit of material… each spool is 2 kg >.<
Right-Bottom: 100x frames and 400x shields delivered last week

Let me know if you or any of your healthcare worker friends need any face shields or earsavers! I’m happy to ship them out.

Again, hope everybody stays safe and healthy out there!

N95 Respirator

TL;DR: I made a working respirator using a small stockpile of N95 replacement filters I have… However, since a local hospital has the appropriate adapters and real respirators, for the greater good, it makes the most sense for me to simply donate my materials.

Two weeks ago, I completed the design of, and successfully tested a prototype N95 respirator. Before everything was sold out, I managed to buy a small stockpile of about forty 3M 5N11 particulate filters, typically used for industrial purposes. Unfortunately, I didn’t find any of the requisite adapters nor compatible respirators.

Luckily, what I did find was this great project called S.A.F.E (self-assembly filtration unit for emergencies) from the Medical University of South Carolina (MUSC) ( to use as a starting point for my own design. In the original design, MUSC recommends using part of a furnace HEPA filter as the filtering material inserted in a replaceable cartridge system. What I believe was the true key to their design, however, is the inclusion of a simple one-way valve. The valve makes it easier to breathe out, prevents excessive CO2 buildup, and extends the life of the filter, but it does not prevent the user from spreading COVID-19 if they are already infected.

To speed up the printing process (and thereby the prototyping and fit-checking stages), I broke the system into three main components:

  1. The mask – this remained untouched from the original
  2. The tube – This component was originally built into the cartridge, and attaches the filter to the mask. The tube also houses the one-way valve, which I thought was a particularly high-risk feature, so I wanted to be able to test it separately.
  3. The cartridge – I needed to replace the HEPA filter design to fit 5N11 replacements.

Since the mask needed no modifications and changes to the tube were minor, I was free to focus my energy on creating a cartridge to fit filter replacement pads. To be honest, even this was a fairly straightforward design job… I took a few measurements of my filter and made a simple enclosure, making sure that the tube would fit into the back. One neat trick I employed to check my fit before printing was that I took a photo of my pad and imported it into my design software to ensure all my geometry looked correct.

Checking dimensions of the part against a photo

While I originally intended the design to be a snap fit to make it easier to swap out the 5N11, I decided that simply sealing everything in place with hot glue, and turning the cartridge into a single-use item would be safer. It is simply much harder to guarantee a seal if end users are the ones making changes.

Cross-sectioned view of the new cartridge system

The tube only took about half an hour to print, so I made that first to test the valve. The S.A.F.E. design called for the use of heavier rubber for the flap, but the only material I had available were thin inspection gloves. Luckily, the design was robust as-is! However, since my membrane material was much thinner and tended to curl, I paid extra special attention to ensure the curl direction defaulted to the closed position. Next, I made the filter cartridge. Since I had checked all my dimensions electronically before, the parts fit together perfectly on my first try—yay! I hot glued a filter in place to make sure the only path for air was through the filter pad itself.

Printed cartridge with a real N95-rated filter

Since the mask took hours to print, I made it overnight. Unfortunately, sometime in the middle of the night, my nozzle clogged a bit and/or my extruder skipped a few steps. This resulted in some underextruded and weak layers, which caused the mask to break as I removed it from the print bed and cleaned up support materials. However, since the breaks were clean, I was able to fix the mask in a quick and dirty way by simply smothering the interface with hot glue. I then attached some rubber material used for sealing windows to the inside of the mask to ensure I could get a tight airtight seal on my face.

Rubber window seals were used to create an air-tight fit

Assembling the mask was simply a matter of attaching the cartridge with tube into the corresponding hole in the mask. I put the mask on and breathed in and out to ensure the valve operated as intended. Then, I did a vacuum test—I covered the filter with a sheet of plastic, and breathed in extra hard… and… success! I was able to hold the plastic up, demonstrating no leaks in my mask!

Successful test of 1-way valve!

Despite some initial success, I quickly realized there were some potential issues with my mask design. First, the positioning of the filter is non-ideal for healthcare workers. Although the filter is out of the way for the doctor, it is facing a potentially exposed area where it is super easy for a patient’s cough to cover the filter itself. Second, my design lacks any sort of exterior grating to protect the filter. Regardless, I saw the two units I did make as a huge success.

An actual N95-rated respirator!

As an engineer, I really love designing and making stuff. However, in this situation, I realized that if any hospitals actually had the real adapters and respirators to pair with my 5N11 filters, then the filters would be better utilized as donated goods. I contacted a few hospitals in my area, and UCI said they could accept them.

Despite giving away my filter materials, not all is lost for me in terms of making pseudo n95 masks! The NIH actually approved of this design for clinical use: and both Keck (USC) and Cedars Sinai accept this alternative N95-esque design:

As an aside, now that I have two printers running, my output has tripled (my 2nd printer has a bigger build area than my first), and with bigger nozzles coming in, I expect my output to increase again to *FOUR* times what I started with.

Hope everybody stays safe and healthy out there!

COVID19 Face Shields

TL;DR: I’ve been busy making supplies for COVID. You can help!

Throughout this lockdown, I’ve dedicated nearly all my spare time to helping out where I can with COVID19 (not even really taking time to doodle! T_T). I doubt I need to educate anybody on the crucial need for PPE in the US. Accordingly, the two main projects I’ve undertaken are:

  • N95 respirator design
  • Face shield manufacturing

While there’s a bigger shortage of N95 masks and respirators, designing one that actually works well is tricky, and it’s a topic for a future post. On the other hand, there are plenty of easy to make open-source face shield designs out there, and hospitals around the globe are accepting them. In conjunction with other PPE, face shields keep healthcare workers safe by preventing droplets from sneezes and coughs from reaching their faces.

The face shields are comprised of three main components:

  1. 3D Printed Frame, ideally PETG, but PLA will work in a pinch
  2. Shield, made from transparent PET, PVC, or Acetate sheets
  3. Straps, optional for some designs

After searching around for a while, I’ve become heavily involved in a dedicated group of local Orange County makers. While we’ve just really started ramping up in the past week, we have collectively already delivered over 318 face shields to hospitals in Santa Ana, Long Beach, Norwalk, and Riverside, and we have orders pending from 24 facilities for over 1700 shields… This includes repeat commitments of 780 units per week.

First batch of face shields ready for delivery!

Personally, I’ve delivered a small batch of initial units to local healthcare friends on the front lines, while I’m working out the kinks in the manufacturing process. This week, I’m on the hook to deliver 55 face shields to local clinics. I’ve just published improvements to two popular designs to thingiverse. The improvements allow parts to be printed in stacks, giving makers more downtime between needing to fuss with printers, and allows for more fully utilized overnight printing. I fully admit that this idea was shamelessly stolen from other members of the OC makers group:

With my current capacity, I’m able to do between 10 and 15 frames per day. However, to keep up with the increasing demand, I ordered another printer, so hopefully I’ll be able to boost my production to nearly frames 30 daily this week. Tiff has pitched in to help with hole punching shields, and she’s been a trooper in allowing this to take over tons of my time (and a lot of the space in the living room), so I wanted to give her a special shout out <3.


If you’d like to help, there’s a few ways you can pitch in:

  1. Find a local open source makers group and see if you can volunteer, especially if you have access to a 3D printer, laser cutter, or have sewing skills. There’s also lots of organizing and logistics support that honestly is just best done at the grassroots level. Here’s a roster of some local groups on Facebook:
  2. Alternatively, if you want to donate to help me with material costs, I’d greatly appreciate it. Venmo @iampip is easy, and anything you can afford to give would be fantastic and will go directly to covering costs. For transparency, here’s what my outlays have been so far (not counting my N95 project, capital investments, and operational costs):

    EDIT: Thanks for all the outpouring of support so far! Any excess donations I receive will be given to Good360. They have a similar mission centered around distributing goods where they need to go, and they have an excellent rating on Charity Navigator:

Booklet Maker

TL;DR: I designed and printed a booklet maker for a friend.  

Instead of completing the Inktober challenge I spent the month of October designing and printing gifts for friends… and I spent November writing about them, haha. I posted about a Darth Vader dice tower here, an Ironman figurine here, and the third project I completed is this booklet maker.

My friend Will reached out for help solving a specific problem: he likes to staple papers into booklets, but needed a way to make them more easily and consistently. We went back and forth with some requirements (number of sheets at a time, staple placement, etc.), he drop shipped a stapler to me, and I started designing.

I began by modeling the classic Swingline 747 stapler from caliper measurements. I needed an accurate stapler model to ensure a good fit for whatever 3D printed part I would ultimately design. Capturing the draft of the side and determining the clearance available during stapler actuation was of paramount importance, so I created the stapler in two components and added movable mates.

Creating the stapler model in two components to allow for assembly mating features proved very useful in determining space available for designing

For this project there were advantages to taking a top-down design approach. In a new part model, I created a layout sketch to place the staplers per the desired specifications 6 inches apart on a line ¼ inch away from the left margin.

Taking a top-down design approach ensured the requirements were met from the beginning. All dimensions were driven from where the staples ultimately need to go.

With the staplers fixed in place, I focused my attention on the design of the main paper retention body. The trickiest part of the design was creating an attachment method that keeps a clear path for the stapler head to reach the crimp area.

After completing a test print to check the fit, I made a few adjustments to the paper backstop height, mirrored the body and connected the two halves with beam extrusions. Pictures speak louder than words, so here’s the build gallery:

Will tells me he’s very happy with the results, and I couldn’t be happier myself.

Action shot! It might take a bit of time for the gif to load

Ironman Figurine

TL;DR: I uploaded my first Thingiverse share! I improved the design of an existing Ironman model by adding pegs to allow for articulation and adhesive-less assembly.

I went on a work trip to Phoenix in early November. Fortuitously, my best friend growing up lives there and loves Ironman like I do. I decided to squeeze in a quick design and print project to gift him.

I found a decent looking Ironman figurine on Thingiverse here. This model is actually a remix of another project—the remixer made the part easier to print by separating the limbs. While this was a good step forward for printability, I further improved the design by adding pegs between the extremities and the main body:

The pegs I added are in red. They allow easy assembly plus articulation.

The boolean tools available in Fusion360 make it incredibly easy to complete simple changes like this. I undersized the peg in the CAD model, but small variations in print settings and nozzle wear and tear make perfect fits a bit tricky. In fact, it took me a few tries to get the pegs working really well, but the prints were short, and the results were worth it:

Assembly in process

Given that this project originated directly on thingiverse, I thought it was only right to give back to the community and share my very first remix here: The number of views and downloads of this model pleasantly surprised me, given the simple and obvious nature of the change I made. I’ll probably consider sharing more stuff going forward… we’ll see ¯\_(ツ)_/¯.

I think the assembly with articulation turned out pretty well—the yellow looks vaguely gold-ish, so the only thing missing is some red paint:

He just needs a paint job

Vader Dice Tower

TL;DR: I made a villainous dice tower for a friend’s bday, combining two of his favorite things—Star Wars and board gaming.

October was a pretty busy month for me with work and fantasy football both ramping up. However, I’m very happy I was able to get some design and project time in. My friend Nick’s birthday was earlier this week, and I wanted to make him something practical yet personalized. Anybody who knows him at all knows how much he loves both board games and Star Wars, so to me, printing a Darth Vader dice tower was simply a no brainer.

For those of you who may not know, a dice tower is a very simple device to ensure fair rolls while keeping dice from flying all over the place and messing up stuff on the table. Dice towers can take on a wide variety of shapes and sizes. All that is really needed is some sort of aperture at the top to put dice in, a path which randomizes spins, and a tray to collect them at the end.

Before I started designing, I did a quick search on thingiverse and other 3d print sharing sites to make sure I wasn’t completely reinventing the wheel. I found a few Vader dice towers, but to be honest, I didn’t think they were very good in terms of amount of detail and general aesthetics. I was fortunate to find a great model of Darth Vader to begin with:

Essentially my plan was as follows:

  1. Reorient and resize the head to maximize the print area on my bed.
  2. Create the dice travel path leading from the top of the head out of the mouth.
  3. Subtract the path model from the head model.
  4. Create a tray to catch the dice
  5. Print the parts
  6. Ship it

Parts 1-4 went incredibly smoothly all within Fusion 360. I successfully printed a ¼ size test part to ensure the path I created could be printed without any internal support structures to minimize post processing work. Unfortunately, I then ran into printer issues I had never previously encountered…

My Monoprice Maker Select Plus (aka Wanhao Duplicator III Plus clone) has been a workhorse without any major issues for years now. Of course, she decided to act up when I was up against a deadline since birth dates are immutable. My printer would randomly stop working and send bed temperature errors before rebooting. I pinpointed the problem to the thermistor on my print bed, but I didn’t have time to mess around. Luckily for me, my neighbor across the street literally has a print farm in his bedroom (15 machines and counting) so I was still able to get the parts made on time. The only unfortunate thing is that his machines are smaller than mine—so he had to scale the size down by 5% to get them to fit. (I found out later that the fix I needed on my printer was incredibly basic: the kapton tape holding the thermistor to the bed loosened over time, thus the printer received intermittent temperature readings.)

Luckily, the 5% reduction in size did not severely diminish the part’s functionality:

It works! May the Force Be With You!

I’m incredibly happy with the results of this project. I enjoyed the challenge of modifying an existing mesh to create a new, meaningful, and practical object. Even though UPS spoiled the surprise by giving Nick a notification about the arrival of a package sent from my area, and the package arrived late, I’m pretty sure he was very pleased upon arrival.  

Thanks for making it to the end of this post—here’s an incredibly sparse build gallery:

ButterBot Spotlight Lamp

TL;DR: I made a robot whose only purpose is to hold up a spotlight… At least it’s a step up from passing butter :D. I am extremely pleased with how this guy turned out. The light is adjustable both in leaf rotation and tilt angle.

A few weeks ago, I desperately wanted a lamp for my nightstand to keep me from needing to stumble around in the dark trying to find the bed while avoiding squishing the dog after turning off the lights at night. Thus, I decided to do the most practical thing, and began designing my own.

I began my design around the idea of creating something in a modular manner. I knew I wanted to have some sort of character holding up the light source, but was unsure about the specifics of what was going to be feasible, and what would be accepted by my landlord to have around the house. I landed on the idea of building around a spotlight—I like the simple shape and general aesthetics and the character-neutral nature.

Over the next few weekends, I kicked around a few ideas and asked some friends for inspiration when I had my eureka moment—THE BUTTER BOT FROM RICK AND MORTY IS PERFECT FOR THIS!!! I am a huge fan of the show, wanted to use up my silk silver plastic filament, and thought I could give this little guy a better purpose than just passing butter. Really, it was a win/win/win scenario.

I don’t have any photos detailing the electronics, but I’ve got a simple ATmega32U4-based Arduino board with a micro-USB interface. I found this awesome inline DC jack power switch and paired it with an even cooler DC jack to micro-USB cable to provide power and add the ability to turn the light on/off.

Designing and implementing my idea was relatively straightforward after deciding what to build. The trickiest part was designing the parts in such a way so they could be broken up and printed in different jobs—the overall size is roughly 7” x 8” x 18” (although the 7” width can change depending on how the spotlight leaves are oriented, and the height can change depending on the tilt angle). I am particularly proud of my insight of creating a domed peg to enable the printing of the main body without the need for supports.

The only thing missing from the completely finished design are a red wire, a yellow wire, and a red led bulb. Anyway, here’s a gallery of my design and build process: