Formula for measuring rectangle

[Avon Lady]

I hope I'm in the right forum!  Does anyone remember a post that explained how to figure out how long to make a chain for a rectangular piece that goes around the beginning chain.  It was something like "subtract the desired length from the desired width, and that will be how long you want to make your starting chain in the middle".  Does this even make sense to anyone out there?!!

[nancybanta]

If you go to this pattern:http://www.ravelry.com/patterns/library/unholey-rectangle it gives you the instructions.  I can't cut and paste it because it's a PDF file.

[nancybanta]

......and just to save you some time - what you wrote is exactly what you do except that you have to add 2 more chains to count as your first double crochet.

[Avon Lady]

Thanks bunches, Nancy!!

[RoseRed]

Pretty much.  How big do you want your finished rectangle to be?

 

If you want it to be 4x6 then the staring chain would be 2 feet.

[ddc]

Thanks. This is information I've wished I had. I don't particularly like large rectangular grannies, but they would be easy charity lapghans. I might like to try one with a "brick" look as well. 

[Granny Square]

To help you rember this, and why it works - assuming your stitch pattern is the same, you are adding the same measurement to the top, bottom, left and right side of the starting chain for each round.  So it will always be (in RoseRed's example) 2' longer than wide.  This works for ovals, too.

[ddc]

I think the odds of remembering this are slim. I wrote it down. 

[RoseRed]

Ya know - when you're only 6 inches into it it looks like you're making a big mistake cuz it's 2 1/2 feet long and only 6 inches wide. lol

 

For 3x4 lapghans I usually make the starting chain a foot long.