Calculation assistance.
 

CT is having a great sale and I'd like to make another queen size OBW. I could just over order, say approx 10 yds, (still a good buy). The repeat of the fabric I have my eye on is 10 inches. I'm thinking 6 wedges per unit. Anyone want to make an educated guess?

If you're asking for help with yardage - I just tried making this with EQ7, and it tells me a quilt 92 x 98 will need 11.75 yds + extra for borders, using 3" triangles. Have never made an OBW but it is on my bucket list.

I assume the triangles should have all sides equal, 60degrees, is this correct?

Do you have Maxine Rosenthal's book, One Block Wonders? On page 17 she says that 9 yards is enough for a queen size or larger quilt. This sounds too general to me, since queen size ("or larger") can vary so much. How big does your quilt need to be, and will it all be OBW's (or will there be borders using another fabric)? By 6 wedges per unit, do you mean you will be using hexagons rather than octagons? Smaller hexagons will use up more fabric than larger ones because there will be proportionally more fabric in the seam allowance.

To give an idea - a large queen (102x112) requires 8 yards of fabric just to cover it (with no seams). Add in the seam allowance and the waste in cutting, and I'm not sure 10 yards would be enough for a quilt that size. But you may be going for something much smaller.

I made a OBW that finished at 48X68 without borders. My fabric had a 24" repeat, and I needed four yards. Based on this, a queen (90x108) would need about 12 yards. I'd get a little extra just in case. With only a 10" repeat, you will have many blocks that are the same. I might suggest that you look for a larger pattern that has a bigger repeat if you want blocks with more variety. Here is the link to my quilt. one-block-wonder-top-finally-finished-t288687.html

Actually you can get an almost infinite number of different blocks from any repeat if you vary the place where you start cutting.

I ordered 11 yards of fabric yesterday from there. 1.5 yards to change a border, 1 yard for binding and the other 8.5 yards for my backing. Less than $60....I consider that a bargain and shipping was free!!

Yep! 11+ yds Id's forgot how much the cuts eat!

Well the size of the Pieces is determined by the repeat? 10 inches so 5 inch triangles

To get more variation in your blocks, I would treat your fabric as though the repeat is larger.

For example, if you buy 10 yards (360 inches), you could cut it into six 60" repeats. Then cut 7" triangles. You would get eight rows of triangles, and every row will be unique. This allows a little bit of room for straightening between rows; technically you can cut 7.5" triangles, but I found that having a bit of wiggle room was very helpful.