trigonometry/geometry help please

Good morning veryone

I know there is someone out there who can help me.

Trigonometry/geometry was never my strong point back in high school (and that's been a while), and at the time I never thought I would have any use for it in real life. As a doctor I don't use it, but who'd have guessed that it would come in handy in my quilting forays!

I am currently working on a sampler quilt. 56 12" blocks, all different. I got most from quilter's cache

formatting link

Right now, the block I'm struggling with is called kite's tail. For this I need four blocks set on point. That means I need four squares with a diagonal of 3.5" (including seam allowance) to make a 12" block. So what size do I need to cut my squares to make a square with a 3.5" diagonal? The instructions on the site say to cut a 4.5" block. I did that. Spent a good part of my class yesterday sewing these pieces together, only to end up with a block that would have done great as a placemat (and a large one at that!). Obviously 4.5" square is too large! So I fiddled around with Pythagoras for a while, but when it came to doing square root calcualtions I gave up. I then fiddled around with an omnigrid ruler and I came up with a measurement of 2.5" squares to give me a 3.5" diagonal. Is this correct? I really don't want to cut into the too large fabric squares until I'm sure; now they are too large so I can easily fix that but if I then cut them too small, it will be a problem!

IS there an easy way of calculating these things? Is there a handy website that will give you measurements like these?

Please help!

Thanks

Claudia

Reply to
claudia
Loading thread data ...

Yes, Claudia, your 2.5" squares will give you a diagonal that's as near as dammit to 3.5". The diagonal will *always* be longer than the side of the square, so if you remember that, you will know in future that the 4.5" could never have been right. I suggest that, if you know you are not strong on this kind of thing, acquire a pad of graph paper - even if it is metric it would help although the measurements are in inches. If you are stuck like this again, just draw out what you want - the abstract becomes visual and any problems usually clear up straight away.

Hope this helps. No doubt there is a ready reckoner somewhere, but with graph paper you don't really need it. .

In message , claudia writes

Reply to
Patti

Reply to
Roberta

Claudia, I'm one of the math impaired quilters of the world, and yet I enjoy resizing blocks to fit my desires. Patti is so right. When in doubt, I draw it out. Once I have the block drawn to the proper size I can trace any needed pieces onto typing paper and then add my seam allowances. With the perfect piece templates in front of me I can measure, cut, and sew any block in whatever size I choose. No need to rely on my math, someone else's measurements or math, a website, or odd formulas. I hope this helps you out of your next quilting math problem. Debra

My art for sale at:

formatting link

Reply to
Debra

To find the length of the side of a square when you know the diagonal, divide by 1.4 (the square root of 2, rounded to one decimal place). Your ruler gave you the right answer; 3.5 divided by 1/4 equals 2.5. To find the diagonal when you know the length of the side, multiply by 1.4.

Julia > Good morning veryone

Reply to
Julia in MN

Thanks for all the help girls.

This thread is being printed as we "speak" for storage in the absolute must keep reference file!

Thanks

Claudia

Reply to
Claudia

InspirePoint website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.