I sew Warm & Natural batting pieces together after overlapping the edges that will be sewn together and cut a straight line thru both pieces. I pin the entire seam by overlapping just enough to hold the pin with the sharp tip of the pins facing the needle. I use a three stitch zigzag stitch over the butted edges created after pulling the pins out just ahead of the needle. This makes a smooth join that cannot be detected by touch either before or after quilting. The draw-back to this method is that machine sewing batting pieces together creates ALOT of lint in the needle bar, feed dog and bobbin areas!

For a long seam, I prevent any obvious seam showing on top by overlapping the two pieces of batting by about two inches. Then I use a rotary cutter to make a serpentine cut on the overlap. That leaves me with two large pieces butted up together and two long, narrow pieces of scrap.

To sew the two pieces together, I use quilting thread (40 wt) and a nice long straw needle. I use the Figure 8 (also called baseball) stitch to seam the two pieces together. This consists of putting the needle down a quarter to half inch from the edge of the batting on the right side, then coming up between the two pieces of batting. Then I put the needle down a quarter to half inch from the edge of the left side of the batting, then up between the two pieces of batting. Repeat. The stitch makes a Figure 8 shape and holds the two sides together firmly.

When I'm done, I can shake the piece of batting and no gaps appear along the seam. The batting acts like it was one single piece all along.

So far I've tried whip stitch, and machine stitchin, and the iron on tape. I don't think I'd by the tape again. It worked, but for the amount of time it takes to macnine stitch the butted edges together, I don't really think it's economical. I'd rather spend the $$$ on fabric - rulers - quilting magazines - Two Buck Chuck :oops: :roll: ;-)

I have a ton of scrap batting and want to join them also so they don't bunch up. Sewing on the machine is a pain in the butt but I do like what you are saying about sewing them by hand. Can you take a picture or two of your method to show us visual learners just how this is done?

This is the method I use because all you need is a needle and thread and you always have them handy.

If I have time to spare, I zig-zag it together, but I am usually pressed for time and use the basting tape :)

Clothide and Keepsakes Quilting are selling tape that allows you to piece batting together! Clothide sells it for 5.00 a roll.

I've seen a link (tutorial) where it was cut in a wide zig zag and then machine sewed together,

I butted up mine then used a zigzag stitch by hand with the last quilt or by machine when I need to.

Cut a piece of batting and sew (long stitches) to the batting you need to increase. I do not overlap the battings but have them side by side and stitch from one bat. to the other. Hope this helps.
hugs