In today’s Sewing Basics post, I’m sharing how to make DIY self-warming blanket on your sewing machine. Self-warming blankets are great gifts for your pets, especially senior pets who may get cold in the winter months. This is a beginner-friendly pattern you can sew in an afternoon and use right away. I’m also sharing how to tie all the layers together using your sewing machine. This is much faster (and easier) than quilting or hand-tying a quilt.
This post contains affiliate links. I may receive compensation (at no added cost to you) if you make a purchase using these links. This post is sponsored by Baby Lock and I’m a Baby Lock Brand Ambassador. This post is part of our ongoing collaboration but all opinions and words are my own. Additional supplies were provided by Oliso and Sewing by Sarah.
My cat is now 76 in human years. We currently live in Burlington, Vermont, known for its long and cold winters, but he still enjoys his outdoor adventures. He is always looking for something warm to cuddle up with at home, and a cozy place to rest his weary joints. He loves self-warming blankets, but the ones available at pet stores are available in limited sizes and colors. I decided to figure out how to make one myself so it could be the perfect shape and size.
You might be wondering what a self-warming blanket is. It’s a bit like an emergency blanket, those silver-y Mylar blankets you often see runners wrapped in after a marathon. Unlike electric blankets which use power and can pose a skin-burning or fire hazard if left unattended, a self-warming blanket has a layer of specially treated polyester fiber inside to direct heat back towards the body to keep you (or your pet) warmer. It’s safer and doesn’t use any external power source, so it’s also more energy efficient than an electric blanket.
While I considered sewing an emergency blanket inside of fabric, I wasn’t too sure that would be washable or long lasting. For my version, I’m using a tried and true, easy-care sewing material: Insul-Bright. If you’re new to Insul-Bright, it’s a needle-punched, polyester material that includes a heat-reflective, metalized polyester film. Once quilted, it can be machine washed and dried. It’s stiffer than batting and has a slightly crinkly sound that my cat loves. You can find Insul-Bright online at Fat Quarter Shop | SewingMachinesPlus | Sewing Parts Online | Amazon. It’s often used for potholders, oven mitts, and lunch bags (since it can reflect cold back from an ice pack).
Scroll down for the DIY Self-Warming Blanket tutorial. If you make your own Self-Warming Blanket, I’d love to see it! Share your progress and questions by tagging me on Bluesky as @UndergroundCrafter, Facebook as @UndergroundCrafter, or on Instagram as @ucrafter. You can also share a picture in the Underground Crafters Facebook group. Sign up for my weekly newsletter and get a coupon code for your choice of one of my premium patterns and private access to my vault of subscriber goodies. Plus, you’ll never miss one of my free patterns again!
DIY Self-Warming Blanket
Sewing Tutorial by Underground Crafter
If your cat or dog is always searching for the warmest part of your home, a self-warming blanket may be perfect for them! This beginner-friendly project can be finished in an afternoon. Customize the size or fabrics on your version to make it perfect for your pet.
Finished Size
- Customizable. My version is a pet blanket for a cat or small dog and measures 31.5″ x 33.5″ finished.
Tools
- Sewing machine with straight and zig zag stitches, and leveling foot or walking foot, such as the Baby Lock Bloom with J leveling foot (zigzag foot). Check out my unboxing of the Bloom below.
- If you can’t see the Bloom unboxing above, click HERE to watch it on YouTube.
- Use my coupon code SAVE10-A424 to get 10% off all machines, accessories and software at Baby Lock.
- 45 mm rotary cutter, cutting mat, and acrylic ruler.
- Sewing by Sarah Wool Press ‘n Lock Tiles™.
- Oliso Mini Iron.
- Dritz quilting pins.
- Denim (jeans) 100/16 needle.
- Class 15 bobbin (or size needed for your machine).
- Dritz Non-Stick Pressing Sheet (optional, if using minky or fleece).
- Pinking shears (optional, but helpful if you are using flannel) or fabric shears.
- Basic sewing supplies (seam ripper, thread snips, etc.).
Materials
- Fabric for top and back – 1 yard each.
- I used flannel (1 yard with a cow pattern for the top and 1 yard in a purple-ish color for the back), but you could use fleece, minky, or quilting cotton instead
- New to these fabrics? Check out my tips for sewing with fleece, for sewing with minky, and for choosing fabric for a quilt
- TIP: You’ll want to be able to differentiate top and bottom, so choose two different fabrics. The top will be closest to the Insul-Bright and will be optimal for your pet to sit on so their body heat is reflected back to them.
- 100% polyester thread for top spool and bobbin – I used black to blend into the cow spots.
- Cotton batting (I used Warm & Natural) – 1 yard.
- Insul-Bright – 1 yard.
- Dritz marking pen.
Instructions
Prepare the Fabric and Sewing Machine
- If you’re using flannel, machine wash and dry the fabric for the top and back to pre-shrink. If you’re using 100% quilting cotton, fleece, or minky, this step is optional.
- Press the fabric to remove wrinkles, using a non-stick pressing sheet if necessary for the fabric type.
- With your rotary cutter, acrylic ruler, and mat, cut the top, back, Insul-Bright, and batting to the same size. I cut my pieces to approximately 33″ x 35″ each (or about 1.5″ larger than desired size across length and width). If you’re new to working with a rotary cutter, the video below demonstrates how to use one safely.
- If you can’t see the video above showing how to use a rotary cutter safely, click HERE to watch it on YouTube.
- Thread the upper and bobbin thread with 100% polyester thread. I used black to blend in with the cow spots. Change to a denim (jeans) needle.
Assemble the “Quilt Sandwich”
- Assemble the fabric layers as follows. (Note that there is no “right side” for the batting and Insul-Bright.) Position the batting on the bottom, position the Insul-Bright on top of the batting, position the fabric for the top right side up (with the wrong side facing the Insul-Bright), and finish with the fabric for the back wrong side up (with the right side facing the top fabric) as shown below.
- With acrylic ruler and marking pen, mark seam lines approximately 3/4″ along each side on the wrong side of the back fabric. Pin through all four layers to secure for sewing.
- Starting with a reinforcement stitch, begin sewing along the seam line using a straight stitch and the leveling foot. (If you’re new to the Baby Lock leveling foot, this video shows how it works.) Alternatively, you can use a walking foot.
- You will sew completely through 3 sides.
- On the fourth side, leave an opening approximately 3″ unseamed, using reinforcement stitches on each side of the unseamed section. Trim through all layers outside of the seam line to reduce the bulk. Be sure to leave at least a 1/2″ seam (and leave a bit more around the unseamed section). I used pinking shears because flannel unravels more easily than some fabrics. Clip the corners on all 4 sides.
Turn Right Side Out
- Insert your hand into the 3″ unseamed opening and pull the right sides out. Use your finger to push out the corners. Fold in all layers on the unseamed section and pin it closed.
Finish Seam
- Starting and ending with reinforcement stitches and using a straight stitch and the leveling foot (or walking foot), sew a topstitch around the top with a 1/2″ seam, closing up the unseamed section.
Change Settings and Test Quilt Ties
- Switch to a zig zag stitch. I used 1-13 (the 2 steps elastic zig zag stitch) on the Baby Lock Bloom and adjusted the stitch width to 3.5mm and the stitch length to 0.4mm. I set the automatic reverse/reinforcement stitch and the automatic thread cutting key (as shown in the lower left below).
- To avoid accidentally destroying your self-heating blanket, create a test piece: a mini quilt sandwich with the same 4 layers you used on your blanket. With speed at medium or slow, start with a reinforcement stitch, work zig zag stitches for about 1/4″, end with a reinforcement stitch, and cut thread. If the test piece looks good on both sides, you are ready to move on to the next step.
Quilt Through All Layers with Machine Ties
- Repeat your machine ties as follows. Position them about 5″ apart from one edge to the other. Start with reinforcement stitch, work zig zag stitches for about 1/4″, finish with reinforcement stitch, and cut thread.
- Continue working across your blanket, alternating the starting position so that your ties are approximately diagonal from each other. I worked all of my ties into the black cow spots on the top.
- Therefore, my ties were less visible on the top than the back. If you’d like them less visible on both sides, use a top spool thread color that is similar to your top fabric and a bobbin thread color that is similar to your back fabric.
- When finished, use thread snips to trim the threads on the entire blanket.