Thursday, July 21, 2011

Jelly Roll Race a/k/a Random Plank quilt

Some tips to figure out how big your quilt will be and whether the strips are vertical or horizontal.
Here are the 3 quilts tops I made in one collage photo.



Measure the length of all of your strips sewn together and divide it by 32 (the number of strips in one direction on every quilt).  This will give you the measurement in the other direction after sewing 5 seams.  The 32 needs to be multiplied by the finished width of your strips (2.5" = 2", 3" = 2.5")

Here are some average sizes if you pieced it Random Plank (straight joining seam) like I did.  If you want to do the original diagonal seam shown on the video, it will be a little smaller.

2.5" strips--- If the number in the left column is smaller than the one in the right column, the strips are horizontal.  When the left column number is larger the strips will be vertical or lengthwise on the quilt.

40 strips = 52.5" x 64"
50 strips = 65.5" x 64"
55 strips = 72" x 64"
60 strips = 78.5" x 64"
65 strips = 85" x 64"
70 strips = 91.5" x 64"

3" strips
40 strips = 52.5" x 80"
50 strips = 65.5" x 80"
60 strips = 78.5" x 80"
70 strips = 92" x 80"
80 strips = 105" x 80"

Disclaimer:  I am only human, I hope I didn't make any errors, and the numbers above are approximate.  Mine came out a little narrower than planned because my seam was a touch wider than 1/4".

14 comments:

Debbie said...

I like all three quilts in the photo. I think you won the race for doing all the math! Your formula will make it easier to plan one of these out...rather than my sew till it is big enough technique. Thanks.

stephmabry said...

I've been trying to explain to my aunt how to figure out the math - she was hesitant to start on a jelly roll race quilt until she knew how big it was going to turn out! - so thanks so much! I'm passing this entry on to her right now! :)

Sheila said...

They are all three BEAUTIFUL!!!! Thanks for working through the math. If one would like their quilt a little larger, they can add a border or two. That's what I did :)

Sharon said...

Very nice, I really like the one on the right. I see you didn't use "stoppers" on 2 of these, I like that look. I'm wondering how red, black and white would look?

Elaine/Muddling Through said...

You're a much better man than me. All that math gives me a headache, so I just muddle. LOL But then again, that's why your quilts are always so gorgeous.

Purple Pam said...

Thanks for doing all the math. I have made two jelly roll race quilts. My first had more than 40 strips in the jelly roll so it was wider than longer if I held it so the strips went across. It became longer than wider when I held the quilt with the strips going up and down. My second one was 40 strips and was smaller.

Wacky Woman said...

Great information. Thanks.

Michele said...

Thank you so much. yes, you are only human but I admire your boundless energy, your enthusiasm, and your marvelous color sense. Yours was one of the first blogs I read and I look forward to your morning posts every day.

Pat said...

The quilts are all beautiful. And I didn't know that you were also a mathematisian (where oh where is spell check). LOL Thanks for doing all the math for us. Hope you are staying cool. I went out to water plants a few minutes ago and it is still roasting outside.

Jean said...

THis is good to know. I haven't done one, but am going on a retreat next weekend, think it would be a fun quilt retreat game to play.

Lynne said...

Thanks, Wanda. I like it so much better than the horizontal stripes and have added it to my "one day" list!

The Calico Cat said...

Thanks a bunch!

Vivian said...

Another advantage of following quilting blogs -- someone else does the math for us. Those numbers are going into my important file. Thanks for figuring all that for us.

I appreciate seeing the three versions side by side. The little dividing squares don't show up as much as I thought they would--just a gentle separation.

Quiet Quilter said...

I am a little behind the times, but am thinking of doing a quilt using a jelly roll. I googled and found your nice post re the dimensions.. Thanks so much. I am going to try one this week and if successful, I may help my grandchildren sew one when I go up to see them the last of April...