Comments on: A fun little quiz

By: Marina Stock

Marina Stock — Sun, 14 Jan 2007 14:43:22 +0000

I can’t answer the first questions, but number 5 I (think) I can.

The end result is a ball, made with 2 pieces one vertical, the other horizontal. (We use them for cricket here in the UK), anyway, the circumference of the ball will be the longest measurement added to the shortest. The longest part is 5.5 times longer than the shortest. So if you know the circumference you want, divide by 6.5. This will give you the width of the shape, the remainder will be the length of the shape. I would then just expand the existing shape roughly on the photocopier and then draw an appropriate bigger or smaller parallel line.

Do you mean notches for lining up?

Marina

By: Laura

Laura — Sun, 05 Nov 2006 04:36:34 +0000

Grade a pillow?? Why bother? Forget the math and the copy machines. Just make the pillows as large or as small as you like! I like to keep things simple

By: graham

graham — Tue, 10 Oct 2006 16:13:45 +0000

ok, this was really easy, except for the part about fusing, because I don’t know what that means. Then again, I make bags. hmm.

1) I lack the english word, in turkish it’s “cit”. Anyway, put a slice/cut into the middle of the bottom of one and into the middle of the side of the other. These will line up when sewn properly.
2) In production, there would only be one pattern, and it would be labeled something like, “2 pieces, one Red fabric, one white fabric, top and side”
3) I don’t know what this means.
4) Up-Side-Up-Side…
5) Forget about math, it makes it much harder. Do what normal people do: use a plotter/photocopy machine. Really. If you want to do it with math, I can explain that if you want. It’s not really about geometry…

By: J C Sprowls

J C Sprowls — Mon, 09 Oct 2006 23:16:51 +0000

I don’t know… I still don’t think we’ve addressed the elongation of the arc and the rest of the ellipse.

Perhaps we need a little Algebra review.

[Insert evil laughter]

By: Thomas Cuningham

Thomas Cuningham — Mon, 09 Oct 2006 22:50:51 +0000

genius!

By: kesimmons

kesimmons — Mon, 09 Oct 2006 18:07:10 +0000

I would fold the piece in half lengnthwise and in half crosswise and grade just the quarter then trace onto a similarly folded pattern paper.

By: Amanda Rodriguez

Amanda Rodriguez — Mon, 09 Oct 2006 03:59:01 +0000

For grading, it seems like there would be a way to photoshop the pattern piece, input the x and y measurements and then decrease the picture whatever percentage you wanted…but are you looking for a non-CAD way to do it?

By: Thomas Cuningham

Thomas Cuningham — Mon, 09 Oct 2006 02:05:19 +0000

If you want to grade it up 1″ in the diameter, you have to increase the circumference by “pie” times the diameter increase, or 3.1415 inches. If you cut the ball though the center, you strike two seams, so each piece gets an additional 3.1415 divided by 4 inches.

Am I missing something here?

By: Alison Cummins

Alison Cummins — Mon, 09 Oct 2006 01:26:52 +0000

Grading: use a grid. Or rather, a series of grids with larger and larger squares. Drawing the pattern in a small grid and redrawing it in a larger grid will make it larger.

By: Tom Willmon

Tom Willmon — Sat, 07 Oct 2006 21:54:57 +0000

J C,

This is mostly hunch, but I think you will have to switch to spherical geometry for this one, origin point at the sphere’s center. Change radius for sizing, then go to trig functions to translate to rectilinear for shaping the skin. No, I’ve never done that. Arrrrgggg!

Tom Willmon
Recovering Engineer
Mountainair, (mid) New Mexico