Sunday, July 19, 2020

Constructing a Kimball Mask - the Laundry List


Kimball Mask instructions for first-time mask-makers

There are many different methods for constructing the masks - Carol's instructions work as do the ones below.  It's a very forgiving pattern.

I think this construction method is especially helpful when trying to custom-fit a mask, or for someone who's never made a Kimball mask before. It's less efficient for mass-producing masks, but it allows for the seamster to stop and make adjustments for individual fit.

Note: child (standard/Big Schnozz, full chin/short beard, big beard) indicates which size; thus 1(2, 2.5, 3)" means, 1" for the child, 2" for the standard and so on.  And these amounts might be customized depending on the needs of the wearer. I haven't gotten all the different sizes filled in yet.

Supplies/notions needed:

  • Fabric - A fat quarter will make 2 to 8 masks depending on the size and number of layers desired.
  • Bias tape (about 1 yard or thereabouts per mask, preferably 1" double-fold)
  • Something for ear loops and ties (can be bias tape, twill tape, t-shirt yarn)

Initial preparation (cutting out, nose dart, and chin gathers):

  1. Trace and cut 1 or 2 mask bodies out (depending on the number of layers desired). If doing 2 layers, repeat steps 2-5 for each layer separately.
  2. Sew nose dart, ¼” seam allowance. Press seam allowance open.
  3. Run two rows of basting stitches very near the bottom edge inside seam allowance, from two gather points marked on pattern (the gather points may vary depending on customization needed).
  4. Gather the fabric, bringing the distance between the gather points to about child (standard/Big Schnozz, full chin/short beard, big beard) 3.5 (3.5, 8.5 9.75)".  When length is correct, knot the basting threads to hold the length static until sewing.   (Note: for my husband who has a pointy-chin and relatively short-trimmed beard, Carol had me gather in the chin area to 3").
  5. Distribute gathers evenly between two points. 

Nose Channel* (Cathy's removable nose-wire variation - see the Industrial Tutorial method to install it inside the top binding.

If making a two-layer mask, this will be done on the right side of the BACK-facing (ie, against the skin) fabric.  If making a one-layer mask, it will be done on the wrong side of the fabric.

  1. Cut a piece of bias tape or twill tape to a length that is equal to the width of the mask along the top edge.
  2. Line it up, so the tape extends all the way to the edges on either side, and affix it in place along the top of the mask.
  3. On the left side, turn the tape under by ½” or perhaps a little more (this edge will remain open so the nose wire can be removed or replaced).
  4. Sew all the way across the mask along the bottom edge of the nose-wire channel.  Sew very close to the edge. Don’t worry about the right side, or top edge of the channel. These will be sewn (turned into a pocket) when the edges of the mask are bound.
Note: when binding the top of the mask, depending on how wide your bias tape or twill tape is, it might make the nose channel too narrow. Adjust placement of the nose channel downward/away from top edge as needed)

* This is Cathy's removable nose-wire variation - see the Industrial Tutorial method to install it inside the bias tape binding.  Putting the nose wire inside the bias tape has the advantage of the most adjustability, as the wire is at the very edge of the mask, and is the quickest for producing a lot of masks. Cathy's variation makes the wire removable, but takes longer.

Binding the edges of the mask:

Over the course of the testing, and development of efficiency techniques, whether to bind the top first, and then the bottom/sides changed a few times.

  • If you are mass-producing, then it works better to do the top first (which allows you to catch the lower ear loop attachments in the binding, saving a step.  
  • If you are customizing a mask, you should do bottom/sides first, then the top, which allows you to leave the lower ear-loop attachments free, so that you can find the best spot to attach it for customization purposes.  This is the method I outline below.

  1. If making a 2-layer mask, place masks wrong sides together (if making a single-layer mask, ignore this step).
  2. Attach binding to sides and bottom of the mask (1” double-fold is easiest). Without cutting the bias tape (yet), unfold one side and line up the raw edge of the tape with the top raw edge of the mask against the back side of the mask (side facing the skin). Line up the cut edge of the bias tape with the top corner, run it down the side, across the bottom and up the far side, clipping as you go.  
  3. Sew very close to the edge, removing clips and adjusting bias tape as you go.
  4. Cut bias tape even with top edge of the mask.
  5. Flip the bias tape to the front, and press, trying to match the folded edges as best you can. 
  6. Top stitch the binding on the front of the mask.
  7. Cut the top binding to about 1” longer than the width of the mask along top edge and fold ½” under on both ends. Attach binding the top of the mask in the same manner as above.  
Note: bias tape won't unravel, so you may cut it to the same width as the mask if you prefer. If using twill tape then it should be cut 1" longer and fold under 1/2" on each side.  

Attach ear loops at the top of the mask, two methods:

Separately sewn ear loops:

  1. Cut two ear loops, 9.75/10.5(11, 11.5, 11.5) Note: for my friend with an extra large noggin (26.5" circumference), I went with 13".
  2. Fold ½” under and sew to top corner, even with top edge. Then skip to the attach ties section below.

Continuous ear loops:

If you prefer to to thread the ear extensions inside the top channel:

  1. Cut a single long ear loop, that = width of the mask along top edge + (tie length x 2). So, if the mask is 9" wide, and if the ear loops are 11", then it would be 9+11+11= 31".
  2. Thread the ear loop through the top channel of the mask and center it so the ear loops extend an equal distance on either side of mask.
This method may achieve a better seal along the top of the mask, by providing a little padding at the top. It cannot be used if the nose wire is permanently sewn into the top edge bias binding.

Attach ties:

  1. Cut 2 ties, 12” long.
  2. Finish one end of each of the ties (if desired, you may omit this step if using bias tape or t-shirt yarn)
  3. Create a loop in the other end and sew. I fold under 1/4" and press, then fold that over by 1" and sew through the 1/4" fold so the raw edge is enclosed. Repeat for second tie.
  4. Thread the loop onto the ends of an ear loop and slide out of the way.  Repeat for the other side.

Attach end of ear loop to side of mask: 

  1. Mark the sides of the mask 2.5" and 3” below top edge.  
  2. Pin the end of the ear loop to the mask, and check fit.  The attachment should be high enough that the ear doesn't drag the mask upward into the eyes, but low enough that the ear loop holds the chin section in place. Use the marks on the pattern to determine where to attach the lower loop. (Most are about 2.5" below the top, with the bigger ones about 3" below). Also check the length of the ear loops.  They should be long enough that when the ties are tied around the back of the head, the ear loops don't touch - they should be about 2-3" apart.
  3. Trim the ear loops if necessary, and Fold under the end of the ear loop and press.
  4. Sew in place at the appropriate attachment point.  Sew the ear loop on bias tape, right next to fabric body. 
  5. Repeat for the other side. 
  6. For extra security, sew again at very edge of mask (optional).

Nose wire:

Make a nose wire at least 6” long (but no longer than the channel), and insert in the nose-wire channel, center, and bend slightly at the center.

Note: so far, I’ve had the best luck with cutting two 6.5” lengths of 16 gauge aluminum craft wire (though I understand floral wire is very good too), bending the ends into loops, and encasing it in a strip of duct tape about ¾” wide (I place the two wires slightly offset so the loops don’t interfere, about ¼” apart, and fold the long edges of the duct tape in to enclose it.) This makes a double-nose-wire strip about 1/4" or so wide. Don't sweat it, if things are a little uneven.

Custom fitting and construction variations:

There will be slight variations in:

  • Base pattern shape and height
  • Chin gather placement and gathering amount
  • Length of ear loops
  • Ear loop lower attachment point 

If you are making multiple patterns for the same person, and  know exactly how long to make the ear loops, and where to attach the lower points, you can construct it with the following variation:

  1. Bind upper edge first, (don’t bother turning under ½” on each side - just cut binding to same width as top edge).
  2. Cut ear loops to the appropriate length
  3. Baste ear loops to mask body on FRONT of mask. One end will be even with the top edge, the other about 2.5-3” below top edge depending on size. Match raw edges of ear loop to raw edge of mask sides. The loops will extend across front of mask. 
  4. Bind sides/bottom (if using a binding other than bias tape, cut the binding so it’s about 1” longer than the length along sides/bottom from top corner to top corner, and fold ends under).  This will bind the mask and attach ear loops at the same time.

Another variation: If using double-fold bias tape for the ear loops, you can create the top binding and ear loops in one step:

  1. Bind sides/bottom of mask as described above.
  2. Cut the bias tape using the continuous method above (width of mask along top edge+ear loop length x 2). 
  3. Fold bias in half along the long dimension, and press.
  4. Match center of bias to center of top edge of mask, and insert the top of the mask into the fold. 
  5. Clip along top of mask. 
  6. Sew the bias tape in one long seam, end-end to end, along the bottom edge. This keeps the bias tape from unfolding, and catches top edge of mask.
  7. Finish bottom of ear loops and ties as described above.

Finally, a mask that fits!

It's time to change gears to a different fiber art (sewing!)

So ... 2020 is the year of the mask.  I have a sewing machine, and when hospitals started asking for masks, I started sewing and sewing and sewing. Best of all, it was something I could do to help out.

I started out making a two-layered surgical-style mask with a pocket for additional filter material. But this style has some negatives - while they fit many faces, they don't everyone.

My husband in particular, found the surgical masks problematic:

  1. They didn't fit his big skull, and his chin came out the bottom when he spoke.
  2. They slid up into his eyes, no matter how much he adjusted he nose wires.
  3. He found ear elastics really uncomfortable.
While I'm a competent seamster (I've made a few nightgowns and dresses for my daughter when she was little, lots of halloween costumes, a couple of formal dresses, and even one pair of jeans) and can follow a pattern, I'm really pretty lost when it comes to modifying patterns or designing, and I really have difficulty understanding the 3D nature of covering a body with fabric. So what that meant, is that finding a mask that fit was going to involve a LOT of trial-and-error.

I tried some of the fitted styles that I found, but they ended up being even worse than the surgical-style for my husband (they were fine for many other people, though!). And I really wanted the mask to fit. Chris was totally onboard with mask wearing, but the best mask is the one that someone will wear consistently, and that means it must both fit properly and be comfortable.   But after the third mask pattern I tried still didn't solve the problems, I started asking around in the sewing groups on Ravelry, and lo-and-behold, someone gave me Carol Kimball's name and email.  And the rest is history. :-)

Carol had me take photos of my husband, showing certain angles and measurements.

Next, she told me how to modify the mask she was testing, and we got it in the very first try. Chris has a long face and a rather narrow, pointed chin, so she had me lengthen the pattern, and then to gather the fabric, into a smaller area under the chin.  The new mask was comfortable, stayed out of his eyes, contained his chin even when he was speaking, and didn't dig into his ears at all.

Then, I found out that a friend of mine, with a seriously large noggin was also having trouble finding masks that fit.  That friend happens to be a medical school professor, who was (and still is) combing through the medical literature, and posting his findings and commentary on FB (and urging people to wear masks). So, I offered to make him a mask. He sent along the same type of pics:

Carol told me what modifications to make - lengthen it it to fit (as I had with Chris's), and because James has a fuller chin, to spread the gathers out over a wider area, and much to my surprise, his fit perfectly on the first try, too.  Carol knows her stuff!  Here's the working-muslin I made him (note the lower strap was still pinned - once he adjusted the straps to an appropriate length, he sent me the measurements, and then sewed the lower strap-end himself).

It's not shown, but I then made him a finished mask out of a fabric printed with images of the COVID19 virus. When I sent him the finished mask, I also sent him his bespoke pattern, so he could have more made if he wished.  He happened to be wearing that mask when he was interviewed by his local TV station, which you see in this video. It shows him wearing it properly at about 0:58 seconds into the video, though he pulled it down for the actual interview (which was filmed from an appropriate social distance!).

Anyway, I was delighted to be part of the testing (if only to test it for a couple of edge cases).  So many thanks to Carol and her testers who welcomed me into their group.

You can find the mask pattern here: The Kimball Mask.

The Kimball Mask

Carol Kimball is a seamster with an agenda.

Carol: "I hope the creative problem-solving keeps going."

In this age of COVID19 which has inspired fraught and fearful feelings in all of us, she wanted to help people find a way to work together and to give them purpose - to make them feel useful instead of powerless.

There were many people who felt there was very little they can do to help fight the pandemic, other than stay home and wait it out - and I was one of them, until I remembered I had a sewing machine, and years worth of cotton fabric leftover scraps.  While I was dusting off my rusty sewing skills, Carol had begun designing a mask pattern that would be comfortable, fit properly, and be easily customizable.

She had some pretty big mask-goals. The mask must:
  • Be a well-fitting and ergonomic pattern that would fit most people immediately.
  • Provide sufficient hand-holding for new seamsters.
  • Be easily altered/customized for face length and width, chin shape, and nose size.
  • Have an adjustable tying-system that accommodates different head shapes and hair styles.
  • Empower folks - give them a way to help others fight the pandemic.  
  • Be efficient to produce in quantity.

Mask can be tied at the back of the neck ...

... or above a bun or ponytail. It is also comfortable on the ears.

Additionally she used the pattern as an excuse to work up industrial efficiency techniques that folks could adapt for use in other projects: Kimball Industrial Tutorial PDF

Carol had a core advisory group and testers that helped bring the pattern to completion: Elisala, Helen, Joyce, Laurie, Lisa, LittleHipkitty, Marianna, Marianne, Meredith, UnplannedCauli, Virginia and myself.  I think I can speak for the group, when I saw we are all delighted and grateful that we were able to be part of this effort, and as Laurie says, "Her work has made people safer and buoyed spirits."

There were other supporters:

  • Lisa D ordered 500 masks to send to healthcare workers in hotspots around the country to use until they got enough N95s, and also to use when not at work, a few neighbors, and underwrote the project with supplies/freight.
  • The UnRavelers group on Ravelry which contributed funds and fabric to the project. They have underwritten other projects Carol has been involved with, including for the Lakota Pine Ridge Indian Reservation, which needed masks to fight the epidemic.  

Child size.

Copyright: Carol gives permission to use/copy/forward/publish this pattern for free as long as her name remains on it. Please do not copy/paste all or portions of the pattern into other patterns. If you have any questions regarding her patterns, contact her at:  herfirstname dot herlastname at [name of our planet]link dot net.

The pattern PDFs provide 10 sizes and variations from child up to XL adult, plus other variations.

Version to (help) contain a beard

For more reading on the Kimball mask see my other blog posts: