I'm wondering how important tear strength really is for most applications. I've been corresponding with one of the most experienced designers in the industry, with literally hundreds of lightweight designs for most of the main brands. He has access to their labs and repair departments, and has conducted wind-tunnel tests to failure. According to him, lack of tear strength is not a cause of failure in the field (at least in anything short of a full expedition shelter) provided you reinforce the stress points properly. For the lightweight silnylon 66 vs silpoly debate, he is a proponent of 20d silpoly. He says its lack of stretch means that it will hold its shape better under load when wet, improving the performance of the shelter. In wind-tunnel tests, it survived north of Force 10. He points out that while nylon is technically stronger in the lab, its inferior UV resistance means that it will quickly degrade in the field and may end up weaker than the silpoly. In his view, they both have poor tear resistance, but this is unlikely to be an issue provided you carry a good repair tape. Against this, some cottage makers are nervous about using 20d silpoly in big winds, but they have a smaller set of data to work with, and no-one I've contacted has had a customer report an actual failure. Dyneema is obviously much stronger, provided you can swallow the price. But it's not being used on expedition tents by mainstream makers like Hilleberg. This may just be because of price or lack of expertise with the fabric. But I suspect part of the issue is the seams - posters on BackpackingLight have found that the seam bonding can fail in extreme cold. Against that, people have been using Dyneema shelters by cottage makers in quite extreme conditions. So there's a lot of uncertainty around this issue. I'm interested in your views.
This comment is gold and provided more info and reasoning than the actual video! I'm pretty sure my next tent will be silpoly, or at least poly and I can coat it my self. Dyneema is not on my radar.
@@sunesnigel I'd go for ready-coated - especially if you are concerned with weight. It's a very technical process. DIY will be very much second best in terms of performance and longevity.
Hi, Thanks for the very interesting video. I have made my most recent tents with silnylon and have been pleased with the general shape and strength and performance, but the condensation is a real negative under some conditions and the stretching with moisture is not welcome. I am preparing to make a tent with breathing polyester fabric (umbrella fabric). I have made small test models with silnylon and polyester umbrella fabric and when set side by side on a damp lawn, I get horrid condensation in the silnylon and none in the polyester model. No condensation in the polyester even when I put a big plate of water under it. What if any problems do you see with using breathing polyester fabric as an alternative for making a tent?
How does the Dynima hold up against bears?
Completely bear proof ;)
I'm wondering how important tear strength really is for most applications. I've been corresponding with one of the most experienced designers in the industry, with literally hundreds of lightweight designs for most of the main brands. He has access to their labs and repair departments, and has conducted wind-tunnel tests to failure. According to him, lack of tear strength is not a cause of failure in the field (at least in anything short of a full expedition shelter) provided you reinforce the stress points properly.
For the lightweight silnylon 66 vs silpoly debate, he is a proponent of 20d silpoly. He says its lack of stretch means that it will hold its shape better under load when wet, improving the performance of the shelter. In wind-tunnel tests, it survived north of Force 10. He points out that while nylon is technically stronger in the lab, its inferior UV resistance means that it will quickly degrade in the field and may end up weaker than the silpoly. In his view, they both have poor tear resistance, but this is unlikely to be an issue provided you carry a good repair tape. Against this, some cottage makers are nervous about using 20d silpoly in big winds, but they have a smaller set of data to work with, and no-one I've contacted has had a customer report an actual failure.
Dyneema is obviously much stronger, provided you can swallow the price. But it's not being used on expedition tents by mainstream makers like Hilleberg. This may just be because of price or lack of expertise with the fabric. But I suspect part of the issue is the seams - posters on BackpackingLight have found that the seam bonding can fail in extreme cold. Against that, people have been using Dyneema shelters by cottage makers in quite extreme conditions.
So there's a lot of uncertainty around this issue. I'm interested in your views.
Seams start to fail before the fabric does
This comment is gold and provided more info and reasoning than the actual video! I'm pretty sure my next tent will be silpoly, or at least poly and I can coat it my self. Dyneema is not on my radar.
@@sunesnigel I'd go for ready-coated - especially if you are concerned with weight. It's a very technical process. DIY will be very much second best in terms of performance and longevity.
@@tullochgorum6323 true true. I had some success with it on nylon though.
Hi, Thanks for the very interesting video. I have made my most recent tents with silnylon and have been pleased with the general shape and strength and performance, but the condensation is a real negative under some conditions and the stretching with moisture is not welcome. I am preparing to make a tent with breathing polyester fabric (umbrella fabric). I have made small test models with silnylon and polyester umbrella fabric and when set side by side on a damp lawn, I get horrid condensation in the silnylon and none in the polyester model. No condensation in the polyester even when I put a big plate of water under it. What if any problems do you see with using breathing polyester fabric as an alternative for making a tent?
How is tear strength affected by UV for these fabrics?
Check out our most recent test on all the fabrics on are you tube!