Microwave-Safe Thread: Can You Microwave Polyester Thread?

13 min read

As we enter winter, the concept of heating bags made of microwavables becomes increasingly appealing. Comfortable, warm and nearly as easy to create like they heat, they’re an excellent option to beat the chill.

While they’re simple to make, people who wish to create their own heating bags must answer some important issues to think about, …. specifically, what fabric and threads are safe to be used in microwaves? In this article, we review some of the most important items you should be aware of.

Can You Put Polyester Thread in The Microwave?


There are plenty of stories of craftsmen using whatever thread that they can find for their microwave-safe bags, never having any issues. All good for them. The issue with relying on some sage advice is that at some time or another, you’re almost likely to be confronted in contact with cold, hard scientific data. The cold, hard reality in this instance is that polyester shouldn’t be within the range of microwaves.

The first question is, what does polyester thread mean? If you’re as common as us, then it’s likely the thread you’re using today. Since it gained popularity in the 1970s Polyester thread has grown to become the most popular type of thread used for sewing, it’s second only to Rayon in embroidery. It is made, as the name implies, from polyester (in itself, a chemical-based, synthetic substance) it is the type of all-singing, all-dancing multi-purpose thread that is the base of every craftsman’s kit.

Polyester thread comes with a variety of advantages. It’s durable and tough, has excellent elasticity, and is very resistant to sun, mold and abrasion like any other fabric you’ll come across. The other thing it has plenty of is plastic. While certain plastics are microwave-safe however, many are not. Polyester thread falls into this category.

If you don’t do not want that thread to melt, or even ignite a fire within the microwave. make sure to keep the thread away.

Can Mercerized Cotton Thread be Microwaved?


For those who are just beginning to sew it is a question of whether cotton mercerized can be microwaved is likely to be followed by a much more important question. What exactly is the term mercerized?

For those who aren’t familiar the term “mercerized” refers to cotton that has been treated with a specific process of finishing textiles. The process involves treating cotton using an emulsion with 20% to 30% sodium hydroxide followed by a thorough cleaning. Along with giving the thread a stunning sparkle, the treatment provides many other wonderful advantages, such as increasing the rate of dye absorption in the process, reducing shrinkage, and enhancing tear strength. Many crafters will discover it easy to work with, including those who typically consider sewing to be more of an exercise than enjoyable.

Now that we are aware of what we have then we have to decide whether it is microwave-safe. In simple terms it is yes. It could be a puffed-up variant of the cotton fabric, however when it’s all done and dusted it’s still cotton and cotton is a fabric which can be treated with just a few blasts of the microwave and not suffer any consequences.

Microwave-Safe Thread Options

If you are looking for threads that are microwave safe the most suitable choice is cotton. Acrylic and synthetic threads can burn or melt when exposed to extreme temperatures. Cotton however can be used without concerns, and so can other threads that are made of 100 100% organic materials (although beware of blends that contain synthetic substances).

Fabrics can be used into The Microwave?

If you’re thinking of designing heating pads for your home, you’re probably thinking whether it’s a good idea to place the fabric in microwaves. In the end, microwaves are designed for food, not for textiles, are they? Actually, the answer is a little more complicated than you think. Although some fabrics are no-no for any type heat source (via in the microwave, or other methods) Some are safe to be zapped without causing any concern.

When you’re trying to choose suitable fabrics, the most important factor to be considered is whether it’s constructed from natural or synthetic materials. In general synthetic materials that are made from plastics must be avoided at all costs. Natural materials like cotton are usually safe (usually the most dangerous thing that could befall them is when they become very hot, but in the event that you don’t plan to cook for hours on end, there’s no risk of them burning and there’s absolutely no chance that melting (two things that synthetic materials can do better than). Along with wool, cotton and muslin also can be used safely as long as they’re free of artificial dyes. Find out more about fabrics using microwaves in our blog post Do you need to microwave fabric?.

Can Minky Fabric be Microwaved?


If you’ve never worked with Minky fabric prior to now, a quick introduction is required before we tackle the issue about whether it’s able to be microwaved. It is available in a myriad of varieties (with silky Minky dimple dots Minky and Ribbon Minky as well as print Minky as the ones most well-known) they are all comprised of the same fabric which is polyester. It’s as warm as fleece as silk, with the same luxurious feel as fur and as soft like silk, polyester is just as well-liked for clothing as it is to make art… regardless though it’s difficult to work with.

Introductions finished, let’s get to the next issueWhat can be cooked in the microwave? Absolutely not. Minky is made of the 100% polymer, which makes it unsuitable for use in extreme temperatures. Create a microwave-able bag using Minky and you’re just as likely to be left with melting mess (or at worst, the possibility of a fire) as you’re a comfortable hand warmer.

It’s important to remember that Minky is not recommended to be exposed to extreme temperatures in any form, regardless of whether they’re emitted from microwaves or not. Whatever your goal is, whether it’s to straighten an oblique seam or smooth an oblique kink, you should avoid the temptation of running an iron on this type of fabric. Not only will it melt, but it’s also more likely to be discolored before hardening to form a hard rough material that’s the exact opposite of what you’re hoping for.

Can 100% Cotton Batting be Used in the Microwave?

Batting (sometimes called wadding) is utilized in a wide range of quilting and sewing projects. It is an extremely warm and dense layer of insulation between fabric. The variety of battings available is as extensive as the variety of possibilities for using it and some of them being the most well recognized being:

Cotton batting made of all-natural fibers Cotton batting is a popular option for those who want the most soft texture and comfort. Generally speaking batting made of 100percent cotton will be about one-quarter” thick.

Polyester batting If you are looking for an batting that maintains its shape well, is strong but not heavy, and provides warmth without weight, then polyester batting is a good option. As with many synthetic fabrics it is not breathable, however what it is lacking in this regard, it makes up for with the resistance to mildew and mold. In terms of the thickness of the batting, most polyester battings come in sizes of 10 pounds (equating one” thickness), 6 oz (1/2″ thickness) 8 OZ (3/4″ thickness), and 4 oz ( 3/8″ thickness).

Wool battingis a soft, lightweight and springy, with crease-proof properties, and extremely easy to work with. wool batting is a fantastic option for those who want to make things as natural as possible. For thickness we’re talking about 1/2 ” for the majority of kinds.

Blends of poly and cotton Cotton/poly batting is generally available in blends of 20 percent cotton and 20 percent polyester. This is a fantastic option for those who want to blend the advantages of cotton and the advantages of polyester.

Bamboo bamboo batting made up of 50 fifty percent bamboo and 50 percent cotton bamboo batting can be described as a highly breathable and machine washable material frequently used to quilt machine.

Bonded bats unlike other kinds of bats Bonded the batting (as its name implies) is joined by using the use of adhesives on both sides in order to ensure that the fibers of batting don’t shift about as well as “beard” (the technical name for the process of pushing fibers through into the material).

Fusible Batting Fusible batting is simple to operate, useful and includes a kind of fusible web which allows you to baste layers.

Needle-punch batting If you’re searching for a highly durable and long-lasting fabric backing for quilts, clothing and blankets, needle punch batting is the perfect choice. The batting is bonded mechanically with needles to form an extremely dense and firm fabric that has excellent insulation properties.

Now that we have a better understanding of the kinds, which one is the best choice for products intended for use in the microwave? If you answered cotton, you deserve some kudos. Avoid mixes that contain synthetic fabrics and stick only 100% cotton Natural fabrics, unlike synthetics have no plastic in them, and while that the fabric will become quite scorching during the process of heating it in the microwave (tip to the experienced: allow it to cool down before taking it off) It’s not likely to cause a mess or ignite.

Will Velcro Melt in The Microwave?


If you’ve ever created an heating bag, you’ll recognize that Velcro is a convenient way to seal the cover. However, the question is… Is it secure?

Some crafters believe that Velcro is safe to microwave for a short time, as long as the liquid’s heat does not get too close and the Velcro itself doesn’t become too hot.

But accidents can happen. Just add an extra few minutes to the timer accidentally and you could be dealing with the worst catastrophe (or at the very least melting messy mess) with your fingers.

If you’re overwhelmed by the ease of Velcro to stop using it completely There are a few ways to reduce the risk of disaster. First, don’t use glue that isn’t a standard glue to secure Velcro to the material. Velcro to the object When heated glue (especially superglue) is prone to becoming unstable and leak fumes that you don’t want to breathe into. If you’re not willing to go through the effort of sewing Velcro onto the material by hand ensure that you go for a non-toxic safe for microwaves instead.

Can Fleece be Microwaved?

Fleece could be cozy comfortable, cozy, and various other wonderful things, but one that it’s not is it’s microwave-able. Although its name might suggest it’s made from wool, or “fleece” of sheep, it’s actually 100 percent synthetic.

Fleece is, just like Minky is made of polyester, which is composed of plastic. Sometimes, you’ll come across a material that is constructed from recycled materials like plastic water bottles. Although this can boost its eco-credentials but it’s not negating any fact that the material is plastic. And as we’ve seen that plastic isn’t a good choice for the microwave.

If you plan to make the heating pad using fleece, choose an fleece cover that is able to be removed prior to placing the heating pad in the microwave. This allows you to enjoy the comfort of the material , without putting yourself at risk of getting into a disaster while making it.

To find the best heating pad that has a detachable fleece cover, take a look at this step-by-step guide.

Rice Heating Bag With Detachable Fleece Cover

What you’ll require

  • 1-yard fleece.
  • 1 yard plain cotton.
  • A huge box of rice.
  • Cotton thread.
  • Sewing tools (a needle or pins, scissors, etc.)
  • Snaps.
  • A piece of paper.

The Method

Step 1- The Rice Bags

  • Cut two rectangles from the cotton. The rectangles should be sixteen inches square by 32 inches.
  • Divide each rectangular in half to create two squares.
  • With the right sides facing each other stitch around the square leaving a 2 inch gap to allow for tuning, and a half-inch seam allowance.
  • Make sure the right side is facing out and then form the newspaper into funnels and then pour about 4-cups of rice in each bag.
  • Sew the gap closed to seal the gap.

Step 2- The Bag

  • Make a rectangle of the fleece that measures at 16 by 32 inches.
  • Cut two more pieces of fabric that measure sixteen inches by 17.5 inches as well as a third piece that measures sixteen inches by twelve inches.
  • Measure the piece to be 16 x 12 inches . Then fold it over every length (these are the sides that measure 16 inches) less than 1 inch. Sew around the edge using the stitch zig-zag. Repeat the procedure with two pieces of 16.75 by 17.5 inches. Fold to one side, measuring 16 inches less than 1 inch.

Step 3 – Construct

  • Take the fabric that measures sixteen by 32 inches. fold it and mark the middle using pin.
  • Repeat the process for the rectangle.
  • Pins should be aligned with the opposite sides facing each other.
  • With small, straight stitches, stitch along the middle of the rectangle.
  • Attach the two squares to the larger rectangle either side, and sew the two squares to each other.
  • Make sure you’re facing the right way Attach the snaps to one of the corners on the interior, and around the middle point.
  • To use, just cook the rice bag’s contents in the microwave before putting them into pockets.

I hope that you’ve found the tips in this article useful. If you know of any other crafters who have the same feelings Please be sure to pass this information along.



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