Check your strips before you sew. Unfold them and see if there is a bow near the fold. If there is you are not cutting straight of grain. I tear (yes, tear!) my ends first and get straight of grain. Starching is very very helpful when sewing. Don't sew too fast.

[QUOTE=AngelinaMaria;5497701]I am sewing a large number of 10 inch long by 1 inch wide 2 and 3 strip sets. The background strip is a regular cotton and the other strips are Hoffman batiks. When I sew 2 strips together, they come out of the sewing machine slightly bowed. The center spot is bowed down (so it looks like a smile when placed on the cutting board the same side up and was sewn) by 1/8 of an inch. I am wonder if there is something I should be doing or changing that would prevent that.





Do not sew from the same side every time. Switch sides it will fix it right up - if your strips are all even. I have found some of my earlier strips were not cut as well as I do now.
Judi

they will bow if they are all sewn from the same end when you add a new strip...reverse the edge you sew on and you will notice the difference. try it

When you press the strips, let them cool before picking them up from the ironing board. If the strips are held up, they will bow.

Maybe setting your seams before you press would help. Once I started doing this I have had better results.

I've found that what makes a fabric "bow" is not so much the cutting or sewing, as the pressing. I drew a straight line on my cutting board so when I press strip sets, I can be sure the seam stays perfectly straight. Also, I have found that if it is possible to do with the pattern you are working with, I piece just half the width of fabric strips, not the full width. They seem to be easier to handle and don't stretch as much. Easier to keep pressed straight, too. Sometimes this is not possible because of your pattern, or because you don't have enough fabric, but if you can do it this way, it's worth a try!

try sewing each strip in a different direction

I was taught that when sewing strips you need to fold them in the middle and pin from the middle out and sew alternating from one side to the other. You may need to rip it out and redo it.

According to Jenny Doan, this will happen if you sew from the same end all the time. Try alternating ends when you sew and see if that makes a difference.

I have learned over the years, when working with anything over 6 inches long...pin pin pin....that keeps everything from stretching