You can sew q power, recommended thread is spectra.
Nak wrote:There are a couple of issues with Q-line to be aware of.
First, no splicing as has been mentioned. All of the strength is in the center fibers which are not braided. The outer housing provides abrasion protection only. Knots are far more tangle prone than splices or even sewn loops. Sewn loops are worse than spliced loops.
Second, even running figure 8 knots cuts your total line strength considerably. I ran a number of tests on my bench tester, and q-line broke at the knot at around 250 pounds tension, pretty darn low. Similar diameter 800# test spliceable line breaks at about 750#.
Good 800# line or even 500# line has less stretch than Q-line. The Q-line pro I tested had about twice the stretch that 800# factory lines have. Line stretch makes a huge difference in how a kite performs. I'm pretty sure I posted my tests years back, but I believe these were close to what I saw: 30# tension, 20 meter lines: 800# factory or Jerry Brown line: 1.5". 500# Factory or Jerry Brown line: 2.25"? Q-line Pro: 3". No name 800# line: 4". The no name line made the kite fly utterly and completely horrible. Too much stretch. Also, it is imperative that you use the same line left to right. Any difference in stretch left to right makes the kite damn near uncontrollable. Not really I guess, but it sure feels that way.
Do not use no name spectra line for the above reasons.
Q-line is certainly easier to make loops with, just tie a knot. However, 800# test line can also be knotted. While not ideal you still end up with about 350# breaking strength. Q-line knots are less likely to slip at all, but can still slip a little bit resulting in different line lengths.
Personally, I'd only use a knotted line as an emergency session saver. But that's everyone's personal decision. Even in an emergency, a quick spliced line only takes a minute or two if you lock the splice with super glue. (ONLY use special super glue specifically designed for spectra. If it doesn't use an activator or similar, it WILL NOT hold spectra. It may feel like it does, but the bond breaks down very easily.)
Interesting in that thread they talk about using Jerry Brown Fishing line for line sets. I use Jerry Brown Line One for bridles on my foils, it is really good and very easy to splice. I think it is higher performance dyneema than standard kite lines. Well it's actually spectra, just a different brand than dyneema, the same brand as q power. Interesting guide to making lines http://www.nwkite.com/forums/t-11649.html
Here is a list of spectra's fiber products https://www.honeywell-spectra.com/products/fibers/
. Their current strongest fiber is Spectra HT 375 with a tensile strength of 45g/den. Dyneema SK75 is 3.4N-4.0N/Tex(31.2-36.7g/den) and SK90 is 3.74N-4.16N/Tex(34.3-38.12g/den). Yet to find sk99.