Friday, December 2, 2011

Let's Do the Math on the HSTs of Part III for the Orca Bay Mystery Quilt...

Since I'm bored out of my mind w/sneezing, coughing, watery swelled up red eyes (those flu/virus gremlins just had to show up), and I can't see well enough to cut accurately or sew, thought I'd try and run the math on the half square triangles (HSTs) for Part III of the Orca Bay Mystery Quilt.  I give you fair warning:  PLEASE check my numbers before you go off sewing 150 of these PLEASE - and I accept NO burden of responsibility if you don't check my math and measurements after you make one or two of these units based on the * square in a square (SNS) method of Jodi Barrows (which I dearly love and swear by, especially if you like strip piecing like I do).

Here's a video demonstration of this marvelous method and a few extras to boot:
(Don't you just LOVE Jodi's chock-full of fabric/tools/goodies studio - I stop by and visit this video from time to time to not only refresh my memory on all the SNS options but to drool over her studio - can anyone say A-W-E-S-O-M-E?!)

DISCLAIMER:  I am NOT affiliated in any way - receive NO royalties, referral fees, and/or money, gifts, etc., from any recommendation from any Vendors online or offline, including the SNS method and tools.  I ordered and paid full-price for ALL my SNS tools, books, and videos, just to clarify...Thank YOU!

OK, now that all those details are out of the way, here's my math so far - according to Bonnie's Part III directions we need:

  • (350) 2" pairs of half square triangles (HSTs in black prints and neutrals) = 2" finished size after sewing the pairs together and 11/2" finished size in the quilt
  • PLEASE see **UPDATE below for change in the center square measurement:  Using *SNS method (above) that means we need: (88) different 3 1/2" or (3 3/8" as stated below in UPDATE) center squares sewn to (30 NOT 120 as previously stated since each completed unite will yield 4 HSTs) different 2" x 45" strips - what's neat about this method, you can make the 3 1/2" center squares out of one of the needed colors - let's say the black print and the 2" strips would then be out of the neutrals, or you can switch and make the 3 1/2" center squares out of the neutrals and the 2" strips would be different black prints - whatever you happen to have on hand in the appropriate measurements (I have a lot of 2 1/2" black printed jelly rolls, so will probably cut them up and use for my 2" strips and have a bunch of hunks of neutral fabrics I'll be cutting for my 3 1/2" center squares).  Just remember, each sewn unit of  3 1/2" center square w/four sides of 2" strips yields four (4) HSTs!
  • FINAL Math tally, the short version:  (88) different 3 3/8" center squares OR (7.5) different 45" WOF 3 3/8" dark strips sewn to (30) different 45" WOF 2" neutral strips, once sewn/trimmed/cut in fourths yield 360 HSTs
Here's my math according to Jodi Barrows SNS methodology to get the center square cut size:  2" cut size of HST multiplied by the magic number of 1.414 = 2.828 plus 1/2" = 3.328 rounded to nearest 1/8" = 3.453 or rounded up to scant 3.5 which translates to 3 1/2" for the center square.  Even though I've checked the math several times, I've yet to sew even one unit since I don't trust myself yet to see well enough to cut and sew accurately (still waiting on those cold meds to kick in ;-).  So again, PLEASE check this and get back to us and let us know if this will work.  As soon as I can, I will do the same..Thanks so much!

**UPDATE:  the 3 1/2" measurement for the center square really needs to be 3 3/8" to be perfect or you need to go really, really scant if you use the 3 1/2" measurement.  I did it both ways and I even mistakenly grabbed a 1 1/2" strip from my quarter square triangle pile and had a heck of a time trying to figure out why my measurements were soooo off - must've been the cold meds, LOL.  I even went with the 3 3/8" center square on my second attempt to figure out what was wrong and started to make the same mistake with the 1 1/2" strip when the light bulb FINALLY went on, H-e-l-l-oooo!

Again, FINAL Math tally - the short version:  For (350) 2" HSTs using the *SNS method we need (88) different 3 3/8" center squares OR (7.5) different 3 3/8" - 45" WOF dark strips sewn to (30) different 2" - 45" WOF neutral strips, once sewn/trimmed/pressed/cut in fourths will yield 360 HSTs.  Since we only need 350 HSTs, you will end up with 10 extra.

So here's my final results using the 3 3/8" center square with 2" strips:

The top square has just been sewn with alternating 2" strips on all four sides of the 33/8" center square.  The bottom square unit has been trimmed using Jodi's Texas 2-step method with the SNS ruler.

I opted to use my 'spinning' cutting board so I could cut through both centers without disturbing the triangles:

And now the moment of truth, after ALL this cutting/sewing/pressing/cutting/sewing/pressing/cutting do we finally have finished 2" HSTs???

YES Indeed we do!  Here's the 'proof in the puddin' as we say down on the farm:

Alrighty then, we are back in the race sooooo.....let's get back to it, shall we?!



  1. Thnks Deb for pointing out Jodi's technique. I also have all the books and ruler, so I think it will be the right time to try ir out!Hope you feel better soon.

  2. Thanks for the link to the video of this technique. It's one I've not heard of before, but looks cool! Hope you're feeling better soon :)

  3. I love this method once again, because of its S-P-E-E-D! While cutting I realized I only needed 30 strips of the 3 3/8" squares since I can get at least (12) strips out of a 45" WOF that's 3 3/8" wide, AND if I really want to finish up quick I could cut two strips from each designated fabric of the center square fabric and I would only need (15) of the 3 3/8" strips. Since I want a nice variation and what Bonnie tends to go for, I opted to cut (30) 3 3/8" strips from different fabrics and I'm almost halfway done! (And starting to feel much better - Thanks for all the well wishes, I really appreciated them yesterday when I was feeling so crummy and thinking of all the sewing I was missing out on :-(.

    I hope everyone was able to take advantage of the time and get a good start on Part III...I'm getting anxious for the Monday morning linky post so I can see everyone's progress...this is really getting FUN ;-)

    Well as I always say, gotta get back to it!

  4. UPDATE: My math was wrong AGAIN - I forgot that you get (4) HSTs out of each completed sewn unit therefore, we only need to cut (7 1/2) 3 3/38" strips out of a 45" WOF and then sew to the 2" strips i.e., 7.5 x 12 x 4 = 360 and we only need 350 HSTs so we're golden ;-).