A friend tagged me in a Facebook post about a surgical mask strap that had been remixed by a Boy Scout for faster printing and less filament usage. My friend knows that I am involved in the Scouting program and I had recently made her grand kids some 3D printed toys.
I immediately downloaded the file and made a few test prints. The STL file is on Thingiverse here and has been approved for use by the US National Institute of Health (see here). I tested this out on a mask I have at home and did a quick post on Facebook tagging several friends and family members that are in the healthcare field asking if they would like one of the surgical mask straps. I wasn’t anticipating the huge response that I received. Within one week, I’ve been asked to make 4,175 of the straps.
Since these are for healthcare workers, I switched from PLA to PETG filament since PETG is food safe and waterproof. PETG can be more easily sanitized which is important. I then had to go on the hunt to locate enough PETG filament to make the straps with. My good friend Jason Hawkins donated my first spool to help get me started. Luckily I have been able to find enough filament to get me through this initial set of orders. The bottleneck I immediately realized was having a single printer. I’ve ordered two more Ender 3 Pro printers, one arrived this week. More details about the Ender 3 Pro and my setup below.
After a week of printing, I’ve sent out 550 straps to 9 different states, all FREE OF CHARGE. I have no plans to ever charge a healthcare worker or anyone else for that matter for a mask strap. I have numerous people contribute to this project to help offset the cost of the filament and postage. One friend brought me 3 rolls of stamps, another purchased and shipped me a roll of red filament, and several have sent donations via PayPal. Because of this, I’ve been able to purchase much more filament, stamps, envelopes, and tape. It has been an amazing series of events that unfolded last week that has me now running a near full-time print operation making over 100 strap a day now. Even my boss and good friend Paul Randal has his two Prusa printers going near non-stop making mask straps for those in need as well. This past week has had me getting up every few hours through the night to take prints off the printer, clean the bed, and start a new print job. Once I get caught up, if I get caught up, I’ll try to get a full nights sleep.
It has truly been amazing, and as I’ve been sending out the mask straps, I’ve been getting lots of messages back and some have even included photos. I’d like to share a collage of some of those here.
![](https://timradney.com/wp-content/uploads/2020/04/3DPrinting-COVID-1024x768.png)
I like the Ender 3 Pro series of printers for a few reasons. The first is the price point. They are very affordable and very capable printers. Second, if you are into electronics, you can add upgrade features to customize your Ender. Third, there is a huge community of Ender makers out there for support.
One of my only issues with the stock Ender 3 Pro printer is that they are a bit noisy, think of a loud dot matrix printer. Simply upgrading the controller board to a silent board eliminates most of the noise. I use the BIGTREETECH SKR Mini E3, you’ll want to research updated firmware for the control board if you replace yours. Once I replaced the control board, I realized the fans were fairly noisy too. Since I have my printer in my office and I work from home, I need it to be very quiet. I purchase a new PSU fan which was 80mm and printed a new cover for the upgraded fan. There are also several 40mm fans, one in the case with the control board and two on the hot end. I used Noctua premium quiet fans for this. One of the issues with replacing the fans is that most replacement fans are 12 volt, however they are 24 volt on the printer. This means you’ll have to purchase buck converters and do a bit of wiring and voltage testing. This is really easy if you are into electronics.
Since I just got two more Ender 3 Pro’s, I’ll be replacing the control boards to eliminate the primary source of the noise. Since these two new printers will not reside in my office full time, I’ll skip on replacing the fans right away.
If you or someone you know needs a surgical mask strap, please reach out and let me know. I’ll see what I can do.