Edges and Tie-Outs on Silnylon Tarp

Lightest weight grosgrain works fine. Actually, is way stronger than necesary.

Webbing is over-kill. There are different weights of webbing with different degrees of over-kill.

On the other hand, if you have webbing and not grosgrain, the extra weight is probably insignificant, depending on your definition of insignicant. You could always weigh it.

One other thing, is I never put any reinforcement in. I just sew grosgrain to hem, so there is 3 layers of fabric. Never had the hint of ripping out. Maybe if you made mountaineering tents for hurricanes it would be different?

Jerry – What width hem are you using? I've been reading the MYOG sewing articles here and elsewhere and many seem to suggest a reinforced corner plus box stitches on the tieout, but I wouldn't mind keeping it simpler. What kind of stitch do you use on the tieout? Thanks.

If you commonly drive a tent stake directly through a tie out or have set up a flapper of a tarp that causes the cordage to saw back and forth on the tarp web, you would be better suited to use nylon webbing (not grosgrain or polypro webbing), Otherwise the binding/grosgrain should be fine.

From project to project, I keep reducing the amount of stitching and reinforcing and I continue to see no sign of wear.

Backwards row of stitches spaced at 2 mm to lock, forward zigzag with 1 mm, backwards 2 mmm to lock.

Hem – fold over 1/4 inch, fold over another 1/4 inch. So, seam allowance is 1/2 inch. Hem is 1/4 inch. Make sure the back, zigzag forward, back is all through 2 or 3 layers of fabric. (Sometimes when I fold, fold the hem, it's not perfect, so the are actually places where the hem stitches only go through 2 layers.

I'm sort of philisophically into minimalism. It would be pretty easy to do more rows of stitches, reinforcing,…

After each trip, examine all stitches to make sure they're not coming undone. "A stitch in time saves 9". If you see wear, then you know you needed more stitches and reinforcing.

If you do more stitching and reinforcing than necesary, you'll put more holes in it which will make it weaker and more likely to leak. Try to avoid putting 2 holes in fabric that are closer than 2 mm.

One place I've had stitches break is at the corners of pyramid. A lot of tension. Silnylon stretches. Straight stitch with polyester thread does not stretch. Threads break, not that it caused any failure in tarp. Now I do a zigzag with 2 mm spacing for maybe 4 or 6 inches closest to corner. Then, seam stretches even though the thread doesn't.

The only time a box stitch is really needed, is like sewing shoulder straps to a pack. It's inherently weak. BPL article says box stitch is best.

I prefer a row of zigzag with 1 mm spacing, then do another row offset by 1/2 so edge of one zigzag is between the two edges of the other zigzag. Then coat with silicone/mineral spirits to strengthen the thread. I've never seen one broken thread.

(David is a professional, I'm an amateur : )

The nylon webbing sounds good for a tie out. I wonder if 3/8 inch would be a good size?

The lightweight webbing that Quest sells is heavier than their firm grosgrain, but much lighter than their medium weight webbing. I like the lightweight webbing for loops where the tension is distributed over both ends. They only stock the lightweight webbing in 3/4" and 1" widths. If they carried it in 3/8" and 1/2", I would definitely use it. I use their firm grosgrain for tieouts and ridgeline daisy chains. I have used grosgrain ribbon in my tarp seams and hems simply because it helps me to make neat and straight hems and seams. I don't mind the reinforcement, but that's not why I use it. I have found that when my seam is also the ridgeline, the grosgrain reinforcement does help to hold the tension.

ridgelines?