Thursday, April 4, 2013

Grrr.. How to do angles?

I need math help!  I clearly do not have my geometry down.

First, I'm working on the borders for the 1st project: Cowboy Corral. I need to add length to the inner border strip on the sides, and according to the instructions, I should be able to sew these two pieces together putting them right sides together, with equal corner tips hanging over and sewing 1/4" seam from little crook to other side crook. (First I cut them at 45 degree angle together right sides up)
 But, this is what happens, they do not make for a straight line.  I tried 3 times. Not working.
What am I not doing correctly?
I fudged and cut some of the edges off and made it work, since I cut them wide anyway.  Not correctly done, but I got the border on the hard way. I'm SO glad the suggestion is to start back with the first project.  This poor quilt is going to be horrible!!  It was the first on the piecing, so it wasn't very precise. Then, it gets the guinea pig trial for the borders, and THEN it will get the first start of quilting!  Yep, this one will have to be designated the doggie blanket.

 I'm going to skip the outer border for now... Anyone have suggestions? Otherwise, I'm just going to use the straight across method! Whew... way too much angst.

I decided after that, I would start with the Heirloom Quilting book, and do some samples.  I bought some muslin, and Fairfield Cotton Classic and thought I would make up these samples as recommended.  These are not batting samples, but straight line quilting samples. ie.. practice.
I was using a blue pencil to draw my lines until the lead kept breaking.  The only thing I had available was red tailor chalk.  I like it better, but it will be interesting to see if it all comes out of the white muslin.  I'll eventually need to get some better marking tools.  Anyone use these triangles?
What kind of marking tools are your favorite? Will a Plain Ole Pencil work?

Anyway, I was doing fine with marking the first 5 examples.  Then, I got to the 6th with the diagonal lines that don't intersect and my mind went blurry. So I skipped it and moved to the next one. 

I used my 45 degree line on my Creative Grid ruler and attempted to make the lines 1" apart. This took a while to mark 1" away from the previous line and then confirm the 45degree angle.  But, it isn't like the way the book suggested with marking the edges with the ruler.  The next one was even more tricky with the double lines.  I still couldn't figure out how to mark, and so I used the "wrong" method again of measuring from the previous line.  Then, I got to the crosshatch one and I just drew a blank, again. 

This is my "issue".  If I want a 1" grid, I think of it as 1" between lines running parallel.  If I measure between the lines at an edge, it is WAY more than an inch between them.  If I mark 1" on the edges, the lines are no where near 1" apart. 
After much contemplation (how embarrassing)  I did, however, finally figure that it measures 1" from top of diamond to the bottom of a diamond. Hmmm. Is that really a 1" grid?   I guess so....but if I put my ruler down, no way, no how does it come close to any square being 1".

Ok, so if that is the real measurement, how do you figure out where to mark the edges of something like No. 6, or 10? (counting left to right, top to bottom on the sample page above?)

I have no idea how to figure how far to mark my lines on the edges and how to make them spaced properly. I'm using a 12.5" or 12" square... which ever works!
Anyone have some good math skills that can explain a "simple" way to figure this?  Grrr..

No. 6 is especially tricky because I need to figure out where to measure on the inside of the square as well as the outside edges.
and No. 10 seems like a day's worth of geometry to figure out the increment measurements to make them spaced properly if marking from the edges rather than just going for it the way of using one line to measure the next.  (which is not recommended because it compounds the smallest error with each new line..)
Ok, anyone able to do the math and explain it to me as well??



5 comments:

  1. Geometry is fun!

    Your angled seam needs to start promptly at the upper straight edge of the underneath piece, and finish exactly at the lower straight edge. If you start it down a bit, there will be a jog in the finished piece - as you've seen. Start sewing exactly at the 90 degree angle formed by the two pieces, and all should be well.

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  2. Geometry twists my brain in funky ways :( I wish I understood it!

    So, on my first attempt, I used my 1/4" seam line more so than the 90 degree corners. (the picture above) I realized they did not meet at the same place, so I DID attempt to stitch as you recommend. Even when I got as close to "perfect" as I could see (by the 3rd attempt), it still did not come out well. There must be more to it? Hmmm... I should know to always go back to the original cutting. Maybe my angle isn't perfectly 45? Maybe that would be the slight "off-ness"? Since I attached it to the border I'll not know, but I'm hesitant to try again with the 2nd border.

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  3. I took a class from my LQS for the basics of quilting as I'm a visual learner, I do not trim my border strips or binding strips until after I sew the seam. Even then, I do get some mismatch hiccups that I end up ripping out. I use the 45 degree angle on my ruler to draw the line I'll end up sewing on.

    After I get a seam I like, I lop off the excess triangle.

    The concern about the tailor chalk triangle is that they can be waxy and do not come out. Not a problem for the practice pieces you are doing, but definitely a concern for a quilt.

    No help here with the math as I haven't tried to mark the samples yet.

    Cheers, K

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  4. Oops - forgot to add - I love your birds. I'm looking forward to seeing the finished quilt.

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  5. Hi Dawn, I think your quilt will be fine when its all done! all the little imperfections that you see when your eyes are about 12" away will be unoticeable when it's quilted, bound and washed.
    we were away this past weekend so this is the first chance i have had to comment on this post.
    I have done seams on the diagonal before and had issues like you are having , it is critical to have the 2 pointy ends extend 1/4" beyond the edge of the other strip and start sewing right in the corner where the two pieces meet. Hope that makes sense!
    I have been using "Frixxion" markers, they are great, you can erase by rubbing or just run a hot dry iron over the lines and presto they disappear. these pens are not expensive and come in a wide variety of colours.
    another way of sewing straight lines is using painters tape, it comes in various widths from 1/4" to I think 2" , is tacky enough to stick to your fabric and not leave a residue. I found a great tip this morning for using painters tape , instead of sewing with your needle right beside the edge of the tape, line up the edge of your presser foot with the edge of the tape. that way you avoid sewing through the tape!
    I think for the diagonal grids , the chart on page 113 of Heirloom Machine quilting is a useful tool . basically whatever distance you want the quilting lines apart you would need to mark the dots on the edge a bit further apart than your measurements, for instance if you want your lines 1/2" apart the dots on the edge should be 3/4" apart, the further apart the lines of quilting the further apart the dots should be.
    anyways i should go , hope i have been of some help. :)

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