Bailey Slow Feeder

TL;DR: I printed a slow feeder bowl for Bailey out of food safe filament and coated it with an FDA-compliant food safe resin. It works, but I think she hates it and me for making it.

I’ve wanted to experiment with 3D prints out of PETG for a while, and finally found some time to do so during this long Thanksgiving weekend. PETG (polyethylene terephthalate glycol-modified) is a 3D-printable plastic with numerous advantageous properties:

  • High strength
  • High density
  • High temperature
  • UV resistant
  • Food safe

The drawback is that it is a bit trickier than PLA (the most typical home 3D printed filament) to print. I invested an hour’s worth of time to adjust settings and complete two quick test prints before deciding I dialed my printer in enough to start a real project.

Our dog Bailey is a voraciously fast eater and I recently learned that various slow feeder bowls existed. However, most of the products on the market seem designed for larger dogs, and I wanted to make something that would fit in our existing holder. Spoiler image below:

Bailey’s custom slow feeder bowl fit perfectly!

The design of the bowl was straightforward. I measured the dimensions of our existing metal bowl, added another mm of thickness of the bowl for strength, added an extruded “B” in the middle to act as an obstacle, and finally made some cuts in the B to allow Bailey to access all the nooks and crannies. I took care to fillet any sharp edges away to ensure safety:

Left: Top view, Right: Iso view. I cut the “B” into an arch so Bailey could reach all the food and made sure to fillet all sharp edges.

The quality of my first real PETG print exceeded my expectations… Based on troubles I’ve read about people having, I expected some blobs/zits or stringing issues, but surprisingly, I didn’t have any real problems at all. The ease of support material separation was shocking too–99.8+% of my support came off in a single piece, and the remaining two pieces were easily removed with pliers:

Top: 3D print in various stages of completion. Bottom: Removal of support material. I was surprised at the great quality, high strength, and ease of support material for my first PETG print.

After the print was complete, I coated the bowl with this neat FDA 21 CFR 175.300 compliant resin I bought a while ago but hadn’t tried out before. The biggest pain point with the coating process was the 48-hour cure time.  Luckily this was a long weekend, haha.

Right: Top view of bowl post resin. Left-Top: Showing off shininess of the bowl. Left-Bottom: Water beading up on the print after washing. Not pictured: 48 hours of waiting, and the popsicle stick, old tofu container, and paintbrush all sacrificed to make this happen.

After washing the bowl with soap and water, I tested it out with Bailey by putting in a few training treats. She did not look very happy…

She eventually came around to eating, but clearly wasn’t happy:

I hope she doesn’t hate me forever because of this…

Does she look most annoyed, confused, angry, or disappointed?

Baymax Cord Lock

TL;DR: A cord lock for Tiff’s hat broke… so I made a replacement shaped like Baymax since I had white material installed in my printer and I was too lazy to change it, haha.

Tiff got a great sun hat from a friend’s beach birthday party last year. I use it almost every day when walking Bailey. I noticed that the cord lock was starting to break, so I decided to make something useful while scratching my maker itch now that the need for PPE has declined.

Since I currently have black TPU (an elastic material not really suited for this application) installed in one printer, white PLA installed in my other, and a severe lazy streak, I needed to design something white and ovoid.

White? Check. Ovoid? Check. Fun? Check Check Check.

With proper source material in place, knocking out the design was straightforward for me. I decided to use the sculpting tools in Fusion 360. Sculpting is great for quickly making organic shapes that don’t require a lot of exact dimensions. Fusion makes it super easy to combine sculpted forms with parametrically defined features as well. I split Baymax’s body into two parts, one main body and a removable front plate to install the spring and legs.

Sculpt and boolean tools in Fusion 360 made designing and cutting the parts up for 3d printing a breeze!

Since the part was very small, I initially had some troubles with Cura deciding some areas (primarily the cut out for feet to retract into the body for cord installation) were so thin that I must not have wanted material there. I solved this problem by reshaping the Baymax body a bit and scaling the parts up by roughly 15%.

Functional? Check.

Overall, I’m pretty happy with the results… despite it looking slightly terrifying, IMO… like Baymax lost a fight. Maybe I should have gone with some sort of squid ¯\_(ツ)_/¯.

As always, hope everybody is staying safe and healthy!

UPDATE: 7/25/2020:

Looking at the Baymax cord lock I made last week depressed me because it looks like his body is getting pierced by some sort of tentacled foe. I decided to replace it by designing a Blooper (the squid thing from Mario games), since it is also white, but looks natural with long arms:

I think Blooper looks better than Baymax cause the strings are tentacles XD

I used all the same tools I used for Baymax to make Blooper, but it was much faster the second time around. While I like this cord lock looks better, but Tiff doesn’t like it because of all the legs, hahaha ¯\_(ツ)_/¯.

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 (https://store.micro-swiss.com/). 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 (https://3dprint.nih.gov/discover/3dpx-013759) 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!

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
Prototypes

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.

Manufacturing

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:
    https://docs.google.com/spreadsheets/d/1JH5uL3WW6PwvwFRe4wqXkheK0-jcGYqaPmb9J3Dr6Ac/edit#gid=179139280
  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):
    https://docs.google.com/spreadsheets/d/17J_YbjUwo13Z-j28TjhQLMCv-tRQZK2QEVbqOquLPa4/edit?usp=sharing

    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: https://www.charitynavigator.org/index.cfm?bay=search.summary&orgid=3752

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:

Laundry Basket Divider

TL;DR: I made a divider for our new laundry bin using material from our old bin and printing some threaded pins to hold it in place.

We used to have a stiff cloth laundry basket, but there were two main problems with it. Whenever I tossed my clothes on it inaccurately (this happened all the time, let’s be real), the walls would buckle a bit under the weight. Secondly, there’s just a single compartment, and I’m allergic to the laundry detergent Tiff likes to use.

To fix the first problem, we actually used the ubiquitous 20% off Bed Bath and Beyond and bought a new hard plastic hamper. To address the second, I got a bit more creative. Since our old laundry basket was cloth-based, I was able to fold it up using binder clips. The divider fit very tightly near the bottom, so I only needed a way to hold it in place closer to the top. I created a pocket on each side by adding two binder clips around where I wanted to place the holder.

The custom design I went with was very simple—it’s a simple threaded pin and retaining nut. I measured the hole I needed to fill, extruded a few cylinders, and added threads, ezpz. About two hours on the printer later, I installed two pins with nuts on the basket and put the divider into place.

I’ll be the first to admit that this isn’t my sexiest design ever, but it’s quite utilitarian.

Here’s a few build photos:

EL Headbands done!

TL;DR: I finished the EL headbands I’ve been working on :D.

I finished up the electroluminescent headbands I described in my post a few weeks ago here. Since my prototype was close to the final product, completing the production was fast after I received the custom fabric components.

As in the prototype, EL wire was passed through the printed channels and connected to a DC to AC inverter for power. I found nifty coin battery sized inverters, which fit directly on the bands without too much interference. The most time consuming portion of the build was attachment of the plastic to the fabric, since I’m bad at hand sewing.

Here’s the build gallery:

Here’s a bonus gif, with a little preview of a flag project I’ve been working on as well…

Thanks Sara and Vi for demo’ing 😀

Lithophane Lamp Shade

TL;DR: I made a lithophane lamp shade for my sister’s birthday. I used an online tool that combined multiple images with specific measurements to create a part that fit around my particular desk lamp. This was probably my longest single part print to date—about 60 hours, but the results were well worth the wait!

I continued playing around with lithophanes and made my sister a birthday present—a litphophane lamp shade! I found another online tool at: https://www.lithophanemaker.com/Lamp%20Lithophane.html. This one lets you enter various parameters to create an entire ready-to-print part very quickly. While I would design this part a bit differently if I were to do it from scratch, the speed of use was pretty undeniable.

I only had a two small hiccups—the size of the lamp retaining lip didn’t quite match what I expected. That is—the cylinder turned out undersized for what I needed. Luckily, I had the foresight to first print only the inner cylinder for a fit check. After I started the print the first time, I realized that I forgot to add supports for the cylinder retaining lip to come out properly, so I had to restart the print after a few hours >.<.

Once I started the print for real, I had the full lamp shade in hand after about 60 hours. This was my longest single part print to date, and I think it turned out incredibly well 😀

The gallery with descriptions below shows the process:

Lithophane

TL;DR: For Valentines Day, I made a lithophane—a 3D object which reveals an image when light is shined through it. The operating principle is basic—different “pixels” are created since thicker areas block more light.

Lithophanes are really cool. Essentially, they’re 3D photos that physically encode pixels of an image by varying the amount of material. Thinner sections of the lithophane allow more light to pass through. I discovered a simple to use, yet highly customizable online lithophane generator at http://3dp.rocks/lithophane/. Upon making this discovery, my mind immediately went to the perler project I worked on last year… I saw I could reuse most of the components (back plate, switch, LED backlight), only making a new front plate. Since I designed the perler project housing in Onshape using top-down design principles, all the modifications only took a few minutes to complete and export for printing.

It took me three tries to finetune my print settings. In the first print, I inadvertently made the image inverted:

My first attempt resulted in a scary looking inverted image… oops!

For the second print, I ended with a lot of blobs on our faces. Clearly this was because the nozzle dwelled a bit too long on the top surfaces since I printed this part flat on the bed:

My second attempt turned out nicer looking with the proper color inversion… but the blobs all over the place were less than ideal.

To correct for this, I reoriented the part on the print bed. I was worried about the part falling over (hence my original print orientation), so I added a really large brim to keep it rooted:

The 12mm brim I added, along with copious glue, helped keep the print from falling over

The third time really did turn out to be the charm, and I was very pleased with how it turned out:

Success! Third time’s the charm 🙂

There’s a ton of ways in which the lithophane idea can be expanded and improved upon. First, I need to redesign the housing unit to incorporate the switch and battery. Others on the internet have wrapped lithophanes around objects like cylinders to make custom lamps, trophies, and other neat projects. The possibilities are endless… as you can see in the summary photo below, you can use pretty much any light source and have the images turn out well:

It was very easy to progress pretty quickly since the parts were fast to print.

I’m excited to play around more with this type of stuff!