Help making a on-point quilt bigger by adding rows
#1
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Join Date: Feb 2013
Location: NE California - no where near the Bay Area!
Posts: 346
Help making a on-point quilt bigger by adding rows
So I can do math through Trig easily, but this math is stumping me. My mom found a pattern for a quilt that has square blocks set on point without any sashing between the blocks. The finished quilt measures 50x60 and doesn't have a border. Each block is 7.5x7.5 and has a hypotenuse of 10.6 inches. There are 50 blocks in the quilt, with the added edge triangles.. The quilt is assembled on point with 10 rows - the first row having one block, row 2 has 3 blocks, row 3 has 5 blocks, up to rows 5 and 6 having 9 blocks, then decreasing from there.
She wants to increase the dimensions of the quilt to 63x90 for a twin bed. We can add borders to help with the dimensions. She can either make the squares bigger (the squares are assembled with 4 squares, 2 short rectangles, and 1 long rectangle) or add rows. I'm thinking adding rows would be best to keep the visual interest of the pattern. What I can't figure out is how many rows need to be added to increase the 50x60 quilt to close to 63x90 (with a possible border)? If this was a quilt with set regular blocks, the math is simple, but with the blocks set on point, I can't figure out how many inches each additional block adds to the overall dimension of the quilt. Any help you can give me would be appreciated!!
She wants to increase the dimensions of the quilt to 63x90 for a twin bed. We can add borders to help with the dimensions. She can either make the squares bigger (the squares are assembled with 4 squares, 2 short rectangles, and 1 long rectangle) or add rows. I'm thinking adding rows would be best to keep the visual interest of the pattern. What I can't figure out is how many rows need to be added to increase the 50x60 quilt to close to 63x90 (with a possible border)? If this was a quilt with set regular blocks, the math is simple, but with the blocks set on point, I can't figure out how many inches each additional block adds to the overall dimension of the quilt. Any help you can give me would be appreciated!!
#4
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Join Date: Aug 2018
Location: Greater Peoria, IL -- just moved!
Posts: 6,101
Here's my graph paper scribbles. I started with a diagonal point layout I drew for something else and expanded it.
There are many ways to describe diagonal sets, I usually use A and B designations. A are the first ones you put down point to point. B are the ones that fill in.
The thick pencil lines (ignore the inner ink lines) show the current size. Each of your blocks will add about 10" for each one that you add to your A rows, but don't forget to add you B blocks. The circles show the blocks that were originally half blocks that are now full blocks.
For the size you want and what you already have, you might consider setting with alternate blocks, you still might have to make a couple.
edit: Forgot to add this link, last year I made an on-point quilt with sashing. The blocks were 7.5" unfinished. Here's a picture and some more about that project if you want to try sashing. I started writing up a tutorial on how to figure out the yardage needed for on-point settings but I sort of abandoned it. Still, I have the start and some good info an will go back to it if it will help.
2019 Fabric Moratorium
There are many ways to describe diagonal sets, I usually use A and B designations. A are the first ones you put down point to point. B are the ones that fill in.
The thick pencil lines (ignore the inner ink lines) show the current size. Each of your blocks will add about 10" for each one that you add to your A rows, but don't forget to add you B blocks. The circles show the blocks that were originally half blocks that are now full blocks.
For the size you want and what you already have, you might consider setting with alternate blocks, you still might have to make a couple.
edit: Forgot to add this link, last year I made an on-point quilt with sashing. The blocks were 7.5" unfinished. Here's a picture and some more about that project if you want to try sashing. I started writing up a tutorial on how to figure out the yardage needed for on-point settings but I sort of abandoned it. Still, I have the start and some good info an will go back to it if it will help.
2019 Fabric Moratorium
Last edited by Iceblossom; 02-04-2020 at 01:52 PM. Reason: better link to Scrap Metal project
#5
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Join Date: Aug 2010
Location: South Texas
Posts: 584
So I can do math through Trig easily, but this math is stumping me. My mom found a pattern for a quilt that has square blocks set on point without any sashing between the blocks. The finished quilt measures 50x60 and doesn't have a border. Each block is 7.5x7.5 and has a hypotenuse of 10.6 inches. There are 50 blocks in the quilt, with the added edge triangles.. The quilt is assembled on point with 10 rows - the first row having one block, row 2 has 3 blocks, row 3 has 5 blocks, up to rows 5 and 6 having 9 blocks, then decreasing from there.
She wants to increase the dimensions of the quilt to 63x90 for a twin bed. We can add borders to help with the dimensions. She can either make the squares bigger (the squares are assembled with 4 squares, 2 short rectangles, and 1 long rectangle) or add rows. I'm thinking adding rows would be best to keep the visual interest of the pattern. What I can't figure out is how many rows need to be added to increase the 50x60 quilt to close to 63x90 (with a possible border)? If this was a quilt with set regular blocks, the math is simple, but with the blocks set on point, I can't figure out how many inches each additional block adds to the overall dimension of the quilt. Any help you can give me would be appreciated!!
She wants to increase the dimensions of the quilt to 63x90 for a twin bed. We can add borders to help with the dimensions. She can either make the squares bigger (the squares are assembled with 4 squares, 2 short rectangles, and 1 long rectangle) or add rows. I'm thinking adding rows would be best to keep the visual interest of the pattern. What I can't figure out is how many rows need to be added to increase the 50x60 quilt to close to 63x90 (with a possible border)? If this was a quilt with set regular blocks, the math is simple, but with the blocks set on point, I can't figure out how many inches each additional block adds to the overall dimension of the quilt. Any help you can give me would be appreciated!!
Another thing you could do is watch Jenny Doan's tutorial on YouTube on on-point blocks. The blocks are actually square, but with a triangle added to each side, the square blocks were set side -to-side, but looked like they were on-point.
#7
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Join Date: May 2012
Location: Central Wisconsin
Posts: 4,391
Think of "rows" on the diagonal, not up or down, or side to side. The first row is from the top left corner, diagonally to the other side, long enough so that the quilt is wide enough. The second row can be below the first; then it will be the same length as the first row. Continue this length of rows until the quilt is long enough. Now each row will be 2 squares less. When the corner is reached, finish the top right corner in the same manner. Do not sew the rows together yet. Make your setting triangles and corner triangles and sew them onto the correct rows. Then sew the rows together.
I make the setting triangles a little larger so that they have a little float and can be trimmed to about 1/2 inch outside the points of the squares.
I make the setting triangles a little larger so that they have a little float and can be trimmed to about 1/2 inch outside the points of the squares.
#8
Senior Member
Join Date: Sep 2013
Location: Saskatchewan
Posts: 838
How comfortable are you with improvising?
My quick estimate is that the existing pattern makes a quilt 60x50", so two of them side-by-side would be 60x100". This is a bit narrower and longer than your desired size, but I would just make twice as many blocks as the pattern calls for. Lay it out, see how it looks, and remove a row or add a border as desired.
The downside of this approach is that you don't know how many setting triangles you need until the very end; if you're not comfortable with that, then you will need to do the actual math.
Good luck!
My quick estimate is that the existing pattern makes a quilt 60x50", so two of them side-by-side would be 60x100". This is a bit narrower and longer than your desired size, but I would just make twice as many blocks as the pattern calls for. Lay it out, see how it looks, and remove a row or add a border as desired.
The downside of this approach is that you don't know how many setting triangles you need until the very end; if you're not comfortable with that, then you will need to do the actual math.
Good luck!