Jelly Roll for smaller quilt?
 

I'd like to use the jelly roll race design to make a baby quilt. Is there a magic math equation for doing this? Can I cut the strips narrower and still use 40 of them or should I simply use fewer of the 2 1/2" strips? Has anyone made a size other than the usual 2 1/2" by 40 strips?

BYW--I loved the jelly roll quilts posted yesterday that varied the lengths of the strips using the usual 2 1/2" strips. It added a lot to the appearance!

When I make a jelly roll quilt in a smaller size, I just adjust the number of strips I use. Then I save the leftovers for other projects...since I will be making quite a few lap quilts for the holidays, I plan on saving the leftovers to add together for another quilt.

From my calculations, once you've sewn a long strip of 2.5" strips together (how long we'll discuss in a minute), you look at building the depth of the blanket first. Your first strip is 2.5", 2" finished. When you fold that strip in half and sew, you end up with 4" finished. When you fold that strip in half and sew, you are now at 8" finished. Again, and you are at 16" finished, and again to 32". Now here's the biggie -- if you were to fold again, you'd be at 64" -- great for a lap quilt but huge for a baby.

If you stop at 32", then you need to decide what dimension you want the other side to be. Let's say you want a square -- then you need 16 x 32", or 512 inches of length, plus some extra for seam allowance. If you were using jelly roll strips of approximately 41", you'd need 13 of them (maybe 13 and a half of one, to be safe).

If you wanted it to be, say 32" x 40", then you multiple 16 x 40" for a total of 640 inches, which is about 16 strips, plus a half of one to get the staggered effect.

I hope this makes sense. I think the number of inches long can vary greatly, but the number of inches that accumulate in depth follows a certain pattern. I think you could use strips of fat quarters, too, as long as you have enough inches total in your first long strip.

I've made 2. Used ABOUT 20 strips in one, then used about 36 fq strips in the 2nd. I put a 2.5' square where the fqs joined. It's my favorite. Either way, cut the 1st strip in half.

willferg's math is more accurate as I just put together fabrics I liked and cut 2.5'' strips from them.

Thank you for responding. I want to try this! I've made a twin sized quilt with this technique but now want to try this for a charity child's quilt. Fast and easy!!

Maybe cut your strips in half so they are only 20-22" long so you still get the variety of colors in your quilt. Maybe that would depend on what pattern you are making.