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Smenta 11-09-2023 07:56 AM

Math formulas
 
I am very new to quilting and I want to make a log cabin quilt . Where can I find a formula to figure out how much yardage is needed to make a king size log cabin quilt. I have search and have not been able to find. I have seen 12 yards for light size and 12 yards for the dark side but nothing saying how to divide that 12 yards with the 3 colors for each size I’m sure it’s not 12 yards for each color. Can anyone point me into the right direction

Iceblossom 11-09-2023 08:35 AM

Welcome to the boards!

Often books will have charts. You can do a simple search on "log cabin quilt yardage chart" that will show some examples that might lead you to a paid site/pattern that might be very much worth it to you. I typically make my own patterns with graph paper or using the Electric Quilt program. You can draw out your block (tape together multiple sheets if needed) and then measure the logs remembering to add 1/2" for the standard seam allowance no matter if your logs finish to 1" or 4" -- is always in quilting 1/4" seam allowance (1/2 for both sides). It is probably easiest to always use the short measurement for your across count, and make longer strips for the log length. For example, if you use a 2" (finished) log, then your cut logs will be 2.5" x some length. Using a 40" wof, you can get (16) cuts per strip. You need to remember both your "short" and "long" parts need to be cut. You then need to know how many blocks you will need -- divide that by 16 to find how many strips. Probably will be some form of a couple of full rows and a partial -- remember that you can use those partial rows for shorter pieces, unless you are using different fabrics for each row.

As a general rule, my queen sized quilts take roughly 10-12 yards, depends on the size of pieces and number of seams. Small triangles can have as much on the back of the quilt as the front! When buying fabric without a specific use in mind, I suggest 6 yards of things you love which is enough to make a focus fabric. I have a scrappy style and am cheap and typically buy 2 yard pieces and figure out how to deal with what I have.

With a log cabin, a lot depends on your log size and how many rows of logs in each block. Also, if your center square will be light/dark/different and what size it is. If you can provide those details we can probably make a better estimation, but I would say from what you've given us I would expect a pretty narrow log with 12 yards each (collected) light and dark -- but certainly not 12 yards per color! Can't help with the breakdown into 3 colors without more info!

There are many resources available to quilters -- don't forget your local library. As a beginner, I feel something like Eleanor Burn's quilt in a day book might be a good place to start. She also has videos. Many quilters have videos and blogs that may be able to help -- as well as us here on the boards!
https://www.quiltinaday.com/shoponline/book//216654

Smenta 11-09-2023 08:52 AM


Originally Posted by Iceblossom (Post 8623465)
Welcome to the boards!

Often books will have charts. You can do a simple search on "log cabin quilt yardage chart" that will show some examples that might lead you to a paid site/pattern that might be very much worth it to you. I typically make my own patterns with graph paper or using the Electric Quilt program. You can draw out your block (tape together multiple sheets if needed) and then measure the logs remembering to add 1/2" for the standard seam allowance no matter if your logs finish to 1" or 4" -- is always in quilting 1/4" seam allowance (1/2 for both sides). It is probably easiest to always use the short measurement for your across count, and make longer strips for the log length. For example, if you use a 2" (finished) log, then your cut logs will be 2.5" x some length. Using a 40" wof, you can get (16) cuts per strip. You need to remember both your "short" and "long" parts need to be cut. You then need to know how many blocks you will need -- divide that by 16 to find how many strips. Probably will be some form of a couple of full rows and a partial -- remember that you can use those partial rows for shorter pieces, unless you are using different fabrics for each row.

As a general rule, my queen sized quilts take roughly 10-12 yards, depends on the size of pieces and number of seams. Small triangles can have as much on the back of the quilt as the front! When buying fabric without a specific use in mind, I suggest 6 yards of things you love which is enough to make a focus fabric. I have a scrappy style and am cheap and typically buy 2 yard pieces and figure out how to deal with what I have.

With a log cabin, a lot depends on your log size and how many rows of logs in each block. Also, if your center square will be light/dark/different and what size it is. If you can provide those details we can probably make a better estimation, but I would say from what you've given us I would expect a pretty narrow log with 12 yards each (collected) light and dark -- but certainly not 12 yards per color! Can't help with the breakdown into 3 colors without more info!

There are many resources available to quilters -- don't forget your local library. As a beginner, I feel something like Eleanor Burn's quilt in a day book might be a good place to start. She also has videos. Many quilters have videos and blogs that may be able to help -- as well as us here on the boards!
https://www.quiltinaday.com/shoponline/book//216654


Thank you for your advice this has given me a lot to think about and the suggestion on getting the book at the library. When I have researched more I’ll be back if have any other questions.

bearisgray 11-09-2023 09:30 AM

Hello and Welcome!

I would like to suggest - for a beginning quilt - either a nine patch pattern or a rail fence. or one called "Warm Wishes"

I consider myself an advanced beginner or a a novice intermediate quilter - and, in my opinion, a log cabin quilt is a bit more tricky to get each block to be the "expected size" than the blocks I suggested.

Two books that I have looked at more than once -

"Quilts! Quilts! Quilts"! by Diana McClun and Laura Nownes. I think you can get it on a second hand site. I prefer the first edition, because they used fewer fabrics for many of the blocks. Of all the books I have - and I have many - this has been one of the most useful ones.

The other one is

"The It's Okay if You Sit On My Quilts Book" by Mary Ellen Hopkins. I also consider this to be one of the more useful books that I have.


1CharmShort 11-09-2023 09:35 AM

Hi Smenta
If you don't mind plowing through a crazy amount of advertising, this link has great info on how to calculate what you may need for your appropriate sizes (scroll way down here):
https://www.feliciasworld.com/log-ca...g-cabin-quilt/

This one is a chart specifically for a finished size 60x88 quilt (click on the topics to the left of the chart for more info):
https://logcabinquiltingforbeginners...c-yardage.html

edit:
one more-this one walks you through figuring out what you need:
https://www.thesprucecrafts.com/calc...quilts-2821956

bearisgray 11-09-2023 09:38 AM

The basic formula for square and rectangle pieces is:

finished size (the part that shows after the seams are sewn) plus 1/2 inch.

Example: If the finished size is 3 x 6 inches, cut a piece 3-1/2 x 6-1/2 inches.

When it comes to triangles, the numbers are different. One needs to add more for the non-right angle points than 1/2 inch.

Part of it depends on how you are cutting the pieces.


Smenta 11-09-2023 11:57 AM

Calculating fabric
 
Hi all I figured out how many blocks I need but If I have 100 12 inch finished blocks using the log cabin pattern how yards of fabric is needed for each color. There will be a center color, 3 dark and 3 light color fabrics

cashs_mom 11-09-2023 12:23 PM

If you look at 1CharmShort's links, they will tell you how to figure out the yardage needed.

Iceblossom 11-09-2023 01:07 PM

Not meant to discourage you but 120x120 (10x10 12" blocks) is pretty darn huge. I usually use the old guide of 3 yards square or 108x108 for king sized, but that might not give you the drape on the sides you want. How will you hold the quilt together? Most long arm quilters only have frames that are 10 or 12 feet long. You can tie the quilt or even force it through a sturdy sewing machine with a reasonably large throat but it will be a handful!

3 rounds each side plus a center can also be hard to pull off in a 12" block. This link shows you a 12" (finished) block and gives directions with 3 colors each light and dark but no separate center.
https://www.bobbininquilts.com/blogs...hnique-tuesday

It uses the 2.5" cuts I was mentioning in my first post, so you will get (16) 2.5 cuts per strip with the other measurement being how deep each strip is.. With 100 blocks, that means you need 6.25 strips per each size and color. so you would cut 7 strips plus have some left over. I am a believer in prewashing and have often been burned with bad cuts so I usually get more than I need, even with most of a strip available for extras. The yardage in Parentheses is what I would buy and is sometimes very close tolerances.

A (light center square/round 1) = 7 strips X 2.5 = 17.5 inches (2/3rd yard)
D+E (light round 2) = 31.5+45.5 = 77 inches (2.25 yard)
H+I (light round 3) = 59.5+73.5 = 133 inches (3.75 yard)

B+C (dark round 1) = 17.5+31.5 = 49 inches (1.5 Yard)
F+G (dark round 2) = 45.5+59.5= 105 inches (3 yards)
J+K (dark round 3) = 73.5+87.5 = 161 inches (4,5 yards)

Smenta 11-09-2023 01:15 PM

Iceblossom

Thank you for sharing i really appreciate you taking the time to explain this to
me. I will have to research more. After reading your response I have to rethink what I’m trying to do.
But thank you for your help.


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