NOTE: I moved this over from another thread so as to not take away from that thread.

This is my first tarp. I made it over the weekend finishing it on Christmas Eve. Itís made of silver 1.1 ounce ripstop, 48Ē wide with DWR. Hereís my process.

1. First I sewed the 2 halves together making the ridge line.
2. Then I folded it along the ridge line and used pins all around the edges to hold the material together and laid out flat on the floor. My ridge is 11 feet. (I only put pins in areas that would be hemmed and not exposed)
3. I came in 2 feet on each edge so the long edges will be 7 feet and took measurement for the end edges. 4. Then I used the cat curve generator that I think Youngblood developed. You have to enter the length and the amount of sag. I chose 3.5" sag for the end edges and 5" sag for the long edges. (I would have preferred having wider material. When I get wider silnylon Iíll make a tarp with deeper curves which I believe will pull it a little more taut)
5. I made two templates on pieces of boards, but each template was only half of the total length of a side.
6. I laid a straight edge along the sides of the tarp from point to point and then laid the template against the straight edge at one point, marked it with a permanent marker, flipped it over to mark the other half of the curve.
7. To cut the material I put pins through both layers of material along and parallel with the marked cut lines. Keep them close the holes won't matter because you will be rolling a hem along the edges.
8. Stitch triangular reinforcements on each corner on the underside. Just sew them down across from side to side and not along the edge.
9. Roll and sew about 8-12" of hem along the edge at a time and you won't even notice that you are sewing a cat curve.
10. When I got near the corners I sewed gross grain ribbon wrapped over the edge with a loop hanging off the ends. It's the same method used on my GG 9X9 camp "Neo Tarp". Some bar tacking is used with the ribbon.

Side View
End View
Corner Detail