The HensNest: Wireframe Face Mask

About The HensNest

The HensNest face mask was designed for the general public as a safer alternative to sewn cloth masks and bandannas. It is not intended for use by medical personnel who should be using N95-rated respirators. The HensNest consists of a simple plastic wireframe that can be 3d-printed or injection-molded, assembled quickly, and used with common household filter materials, like clean furnace filters or certain reusable tote bags. The plastic wireframe is dishwasher and disinfectant safe; and the filter material should be disposed of and replaced after heavy use. Depending on the filter material that is used, The HensNest provides four to eight-times the protection of sewn masks and bandannas. 

The HensNest 3D Printed Wireframe Face Mask

Requesting a HensNest

The HensNest was designed by a small, volunteer team of designers and engineers at University of Delaware. At present, our production capabilities are limited, and we are prioritizing donations in our local community to high risk individuals (elderly and immunocompromised individuals), home caretakers for high risk individuals, and those working in high exposure risk environments (grocery store workers, delivery persons). In the meanwhile, complete this application to request one of our limited number of masks.

We are actively pursuing partnerships with manufacturing firms to mass produce The HensNest for wider distribution locally and regionally. Please check back frequently to learn more about how we are freely distributing these masks to the general public.

Donate to HensNest

The HensNest Project is funded through the generous support of our industry and community partners as well as individuals like you. We are committed to supplying high quality HensNest face masks to at-risk members of our community in the MidAtlantic Region and to helping other communities ramp up production of their own HensNest masks. If you would like to help us in our efforts, we would be grateful for financial contributions of any amount. Please select “Other” and specify “HensNest” for your donation. Donations go directly to materials and production costs to supply masks free of charge.

Using Your HensNest

The HensNest does require some assembly and routine care. The product will be delivered to you with the 3-part plastic wireframe, several pre-cut pieces of filter material, and elastic straps. Follow the instructions below to assemble your HensNest mask.

Please note that there are two versions of the HensNest that are currently in circulation, and each has slightly different assembly instructions. Click on the link corresponding to your mask version to see detailed assembly instructions. The detailed assembly video below provides instructions for assembly of both versions of the mask.

To clean your HenNest, dispose of the filter material and clean the wireframe in the dishwasher or with a light-duty cleaning product (bleach or alcohol-based). Replace with a fresh filter swatch that has been cut to size (approximately 10 inches x 10 inches).

The HensNest will work with various filter materials that are easily sourced around your house. We have tested the performance of several common filter materials (read the complete report) and found several that worked very well. Results are summarized in the table below.

Table 1: Relative filtration performance of one-ply of common household filters compared to two-ply cotton fabric when used in HensNest Face Mask. Refer to complete report for more details.

PerformanceFilter Material
8xPleated HEPA air filter from your home furnace
4xBlue shop towels (fiber-based, disposable)
4xReusable tote bag material (non-woven plastic, not canvas)
3xHeavy cotton "tea towel"
1xTwo-ply cotton fabric

Making Your Own HensNest

If you have access to a 3D printer, you can make your own HensNest! Simply download the design files and manufacturing instructions from GrabCAD.

We’re continuously improving the HensNest design, so make sure you download the latest version. Also please let us know about your experiences making your own HensNest face mask and how we can improve our design. Communicate directly with our design team through our GrabCAD account above.

Industry Partnership Opportunities

The HensNest project was founded to provide “makers” large and small the design tools to manufacture and distribute high quality masks to their local communities. The HensNest design is entirely open-source and ready for production. Current industry partners who are involved in manufacturing or product sourcing include:

Celanese Corporation

Donate Delaware

NegriBossi North America

Procter & Gamble Company

Stratasys Corporation

If you are an industry representative who is interested in joining our efforts, please contact our team. We are here to help you get up and running and network you with other industry partners.

The HensNest Team

The HensNest is a collaborative project from the University of Delaware’s (UD), home of the Blue Hens. The design was conceived and early prototypes manufactured in The Design Studio, which is an undergraduate teaching and learning makerspace in the UD Department of Mechanical Engineering. The Design Studio is part of the UD MakerNetwork.

Lead Designer: Whitney Sample
Design Support: Arnav Prasad, Jeff Ricketts
Logistical Support: Jenni Buckley, PhD; Ajay Prasad, PhD; Paul Costello, Ann Lewandowski, Emily Suwala
Safety & Product Testing: Mike Gladle, Krista Murray, Cathy Fromen, PhD, and The Fromen Lab
Clinical Consultant: Lisa Lattanza, MD (Yale Univ, The Perry Initiative)
Communications: UD College of Engineering Communications Team: Julie Stewart, Joy Smoker, Vicky Tosh-Morelli


The HensNest should be used only as a last resort when FDA-regulated masks are not available for home or medical use. The HensNest design files and manufacturing notes are presented “as is” by the University of Delaware in a good faith effort by all parties to help with the COVID-19 pandemic. If you use, copy or share this Item, you agree to utilize these files for production of masks at your own risk and comply with any state and federal guidelines for use of these devices. You also agree that the University of Delaware: (1) Disclaims any warranties related to fitness of use, non-infringement, or compliance with regulatory standards; and (2) Have no liability for any claims of any kind made by person, either as a result of use of or as related to the Item. 

UD MakerNetwork

The University of Delaware MakerNetwork empowers students, faculty and staff to turn ideas into reality through the action of making things. Click here to learn more about the MakerNetwork’s efforts to make personal protective equipment in during the COVID-19 pandemic.

HensNest: 3D-Printed Face Mask