Making a Microwave Heat Bag





Introduction: Making a Microwave Heat Bag

About: History geek; sewing nerd.

Perfect for aching joints or warmth on a cold day, and really easy to make!

Step 1: Materials

You're going to need:
Thread (I'm using gutermann sew all)
Filling (Rice/Wheat/Feed corn/Buckwheat hulls/Barley/Oatmeal/Beans/Flax seed/Cherry pits)
Two pieces of a 100% cotton material roughly 14cm wide and 50cm long.

Essential oil (I've used lemon scent)

Because this project will be going in the microwave, a material that won't melt in heat is essential. For that reason I've specified 100% cotton. My favourite is flannel/flannelette/winceyette as this has a soft and slightly cosy texture while still being cotton.

"Fat eighths" are particularly good for this sort of project, especially when you have a lot of them in your stash.

Step 2: Filling Preparation (optional)

About a week prior to your project you should prepare your filling if you wish to add a scent.

I did, and so I put the rice I'll be using into a sealable bag and then added several drops of essential oil to it to my own tastes for how strong a scent I would like. It will dissipate some once it has been put into the heatable bag, so keep this in mind when adding the oil.

Seal the bag and leave to marinate for as long as possible before use. I usually go for some time between 4 days and 3 weeks depending on how organised I am.

Step 3: Pinning

Line up your two pieces of fabric with the right sides facing each other and pin in place round edges.

If you're a bit scatterbrained you may find it useful to mark with a pencil or disappearing marker a gap of about 4cm that you'll be leaving open when you sew.

Step 4: Sewing

Sew around all 4 edges, leaving a gap of about 4cm in one of the short edges for turning and filling.

Depending on how confident you are in your skill, aim for a seam from between 0.5cm and 1cm. I usually use a 1cm seam, but go as low as 0.5cm when my fabric is less wide than usual.

Step 5: Clip, Turn, Press

Once you have sewn your edges, clip the corners to reduce seam bulk and then turn your sewing right side out through the hole you left. Poke the corners through and then press so the seams look nice and sharp. You can skip the pressing, but the final appearance is nicer if you do press the seams.

Step 6: Fill

Using the hole you left, insert the filling for the heat bag. Aim to fill the bag to just over half way. You'll know how much more to add when you fold the fabric over. If the unfilled end is longer than the filled end, keep adding filling.

Once your bag is filled to the right level pin the end closed.

It's easiest if you can use a funnel for this step. In the absence of a proper funnel you can use a piece of paper or card that has been folded into a funnel shape.

Step 7: Top Stitching

Close the bag, and finish it nicely, by top stitching around the edges. Try to get this stitching as close to the edge as possible to make the closure of the hole as neat as you can.

I tend to start my stitching as close to the end with the filling in as possible and then move the filling within the bag as I need to so I can stitch all the way around.

If you find topstitching the whole outside rather difficult or fiddly, then you can settle for only topstitching the open end to make sure the hole is closed.

Step 8: Heat and Enjoy

Now your heat bag is finished! The amount of heating it will need will depend on both the filling and the density of the filling. I tend to start at 2 mins and decide whether it needs more or less from there. However long it is you decide on, heat in the microwave and enjoy!



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15 Discussions

One more question-did you use an equal amount of each ingredient? Thank you!

Hi! What kind of beans work best? Did you get the ingredients at a store like Sprouts? Thank you! :)

This is my first sewing machine a brother cs6000i and this is my first sewing project. It would be helpful if you had type of presser foot and also if you backstitched to seal when you finished the inside sew. Sorry if that’s a dumb question but since I’m beginner I’m trying to learn and sew it correctly but I like the post and I am almost done with mine. Thank you for the tutorial!

1 reply

Susanna, if in doubt, always backstitch at start and at end of every stitch you make. Always assume they are using the orginal presser foot unless it tells you different. This is the way with every instructions. Glad you are into sewing. As with anything, practice makes perfect. Practice sewing on different fabrics and make sure you treads are stitching correctly. This is important. I still always do a practice stitch to make sure it is sewing correctly. Use your manual to help you. Really read what stiches do. You will be a pro in no time. Happy sewing!

I've been making these for years. I love them in the winter, I take one to bed with me every night and pace it down by my feet to get and keep my toes warm as I lay and read a book. They make great gifts.

Looking forward to giving something like this a go. Thanks for the tips. :)


1 year ago

Got one on my neck! they're great! I"ve received a couple as gifts and cannot wait to make my own! Thank you for these clear instructions!

Got the 8th and all! Namaste!

Umm first of all..... It kinda doesn't give ally of advice but it did help me though.. :)

I have made several through the years but never added any scents. Does the scent last? Mine just smell like rice.

Made one a bit differently. Used muslin for the inner bag and made an outer bag out of flannel and sewed velcro for a quick way to be able to wash the liner.

2 replies

good muslin is 100% cotton and can be used in cooking. But the Velcro is plastic synthetic. Maybe a drawstring closure with cotton cord would work?

Hmmm.. I already got a store bought bag, but I sure could prettify it with a fleece lining ... Thanks !

So cute, I LOVE owls! I have been meaning to make a heat bag for some time but haven't gotten around to it. You have inspired me to make finally make one!! :)

Great job - love these things :) Have a few at home and can't survive without them in the winter.