According to the directions on the tater batting you can use serger to sew bag together. Since my serger thread is all polyester I took piece of tater batting and serged edges then put in microwave. IMMEDIATELY caught fire. What a nasty smell!

So, even though the directions don't say use cotton thread I know because all of you here on the board have emphasized it and will be making my bags with 100% cotton thread on my sewing machine instead of the serger.

I check all my fabrics first. It is a good idea to be sure everything is cotton for projects used in the microwave. Thanks for the info on thread.

before you toss that thread...test it with just fabric and batting...

sometimes if the fabric is NOT washed first, the chemicals on the fabric are what catch fire!

I had the same thing, my thread caught my bag on fire! Good of you to do a test and share these results.

Thanks for this info! I was going to make some for my sisters for Christmas presents!

I was told to prewash the fabric has to be 100% cotton, 100% cotton thread and the special batting

Where do you find the special batting? I've looked on line, Hobby Lobby and Joanne's. Closest I've found is Warm'n Natural with no glue or resin and doesn't say that it has scrim.

You should be looking for warm tater batting and I believe Connecting Threads carries it and probably a lot of other places.

I even went to warm'n Natural web site and couldn't find it Will give connectig threads a look

I purchased the warm and tater batting from Jo-ann's. It is packaged in bags.