Membrane Sil 15 denier Review

**Dave-O** · 01-05-2015, 00:21

Originally Posted by squidbilly

After one week, I have discovered a big problem: I'm going to have to find something else to use as a seam-sealer. After repeated flexing (packing and unpacking) the Silnet starts to separate from the material. Permatex Flowable Silicone doesn't work any better. In fact it doesn't hold as well.

Until I find something that works better, as a seam-sealer, I'd have to recommend using the grosgrain binding method of joining the halves of your tarp.

Squidbilly,

Thanks for posting this. I haven't received my Membrane Sil yet, but the design I was going to use was going to require seam sealing. Thanks for saving me some time and money!

Sincerely,
Dave-O

**doogie** · 01-05-2015, 07:47

So far in all the tarps that I've made I used DIY Gear Supply's seam construction (I think it is a French Seam). I have my Membrane SIL and am ready to move forward. Do people have links to suggested seam construction...I may opt for a design that does not have the seam down the ridgeline if this is likely to be a problem. So far I have seam sealed with homemade sealer. Perhaps that is the way to go since you can make it thinner consistency to allow it to penetrate the thread holes rather than stay on the outside.

On a different note, are shock cords recommended on the tie outs like they are for regular SIL Nylon or Argon SIL?

**Dave-O** · 01-05-2015, 11:59

Originally Posted by doogie

So far in all the tarps that I've made I used DIY Gear Supply's seam construction (I think it is a French Seam). I have my Membrane SIL and am ready to move forward. Do people have links to suggested seam construction...I may opt for a design that does not have the seam down the ridgeline if this is likely to be a problem. So far I have seam sealed with homemade sealer. Perhaps that is the way to go since you can make it thinner consistency to allow it to penetrate the thread holes rather than stay on the outside.

I was originally going to use the full width of the material for the center section of my tarp and sew on the sides. Streamline and Gargoyle have different designs that do this. However, I think I'm just going to imitate the Warbonnet ridgeline construction explained by SirMarkos and Boston here. I think it would be very interesting if someone could figure out how to use the combine both concepts to have grosgrain covered seams to attach extra material to both sides of a center section. It would let you create some interesting designs much faster. Unfortunately, I think you would have to make the seam curve somehow to make sure water ran off the tarp correctly instead of building up and the grosgrain and eventually leaking.

**doogie** · 01-05-2015, 12:56

I don't understand how covering with grosgrain eliminates leaking. Don't you now have 2 rows of stitch holes? At least a flat felled only has one row of stitches that go all the way through.
I saw a video on youTube (sailrite I think) that suggested putting a basting tape in the seam, and they said that the tape would help eliminate leaking, but they were dealing with standard waterproofing and not SIL.

**Dave-O** · 01-05-2015, 13:36

Originally Posted by doogie

I don't understand how covering with grosgrain eliminates leaking. Don't you now have 2 rows of stitch holes? At least a flat felled only has one row of stitches that go all the way through.

I don't have a tarp with this design yet, but I believe it's because the grosgrain covered seam is oriented vertically and at the apex of the ridgeline instead of laying flat so water doesn't really run over it.

**squidbilly** · 01-05-2015, 18:59

Originally Posted by doogie

So far in all the tarps that I've made I used DIY Gear Supply's seam construction (I think it is a French Seam). I have my Membrane SIL and am ready to move forward. Do people have links to suggested seam construction...I may opt for a design that does not have the seam down the ridgeline if this is likely to be a problem. So far I have seam sealed with homemade sealer. Perhaps that is the way to go since you can make it thinner consistency to allow it to penetrate the thread holes rather than stay on the outside.

On a different note, are shock cords recommended on the tie outs like they are for regular SIL Nylon or Argon SIL?

Homemade sealer may be the way to go. As far as shock cords on the tie-outs: I haven't tried pitching it (membrane tarp) without shock cord tensioners. Although it has very low stretch along the warp and waft, the material still has some bias stretch: a lot less than SilArgon, but still there is some.

**squidbilly** · 01-05-2015, 19:02

Originally Posted by Dave-O

I don't have a tarp with this design yet, but I believe it's because the grosgrain covered seam is oriented vertically and at the apex of the ridgeline instead of laying flat so water doesn't really run over it.

I think that is correct.

You could always mix up some DIY silicone mixture and paint the grosgrain with it.

**squidbilly** · 01-05-2015, 19:49

Originally Posted by ripstopbytheroll

Thanks for letting everyone know Squid. If you can report back on what you find I would appreciate it. I have to think there is something out there that will work. For what it's worth, I've never seam sealed my tarps and have yet to experience a leak. Then again we are using a different seam from the flat-felled. It also never hurts to be totally sure.

Are you using the Warbonnet seam (grosgrain bound)?

I have some of this stuff: http://www.loctiteproducts.com/p/cnt...e-Adhesive.htm Last night I painted it onto a practice seam on a piece of silpoly. It dried to a thin, transparent and flexible layer. I can scrape it off, but it is much harder to do so than Silnet. Also, where I peeled it off, it tore along the line of stitches and remained around the stitching.

I have not had the time to seal and test the Membrane tarp with it, but I think this might work.

**genixia** · 01-05-2015, 21:14

Remember that you're trying to get it to plug the holes made by the stitching, not coat the already waterproof fabric. Any sealer that is laminating the fabric is wasted sealer and extra weight and thick sealer is not well bonded to the fabric will de-laminate. I used SilNet on my argon tape and it is way too thick for my liking. Try thinning your sealer more. Kyle states on the page that the coating is silicone, but he also mentions some kind of special finishing process. Maybe that finishing process is interfering and he can find out from his vendor an appropriate approach to sealing. One more idea, wiping the seam with thinner before applying the sealer might help the bond. Some testing with scraps is in order....

Mad skills you're displaying there. I can't believe you're hoarding that woodland silargon though.

**squidbilly** · 01-05-2015, 21:25

Originally Posted by genixia

Remember that you're trying to get it to plug the holes made by the stitching, not coat the already waterproof fabric. Any sealer that is laminating the fabric is wasted sealer and extra weight and thick sealer is not well bonded to the fabric will de-laminate. I used SilNet on my argon tape and it is way too thick for my liking. Try thinning your sealer more. Kyle states on the page that the coating is silicone, but he also mentions some kind of special finishing process. Maybe that finishing process is interfering and he can find out from his vendor an appropriate approach to sealing. One more idea, wiping the seam with thinner before applying the sealer might help the bond. Some testing with scraps is in order....

Mad skills you're displaying there. I can't believe you're hoarding that woodland silargon though.

Yeah...that's been my way of looking at seam-sealing. I typically use a syringe and a sampling needle to apply the silnet or permatex just on the line of stitches. This may be a case where the homemade mixes are better.

Thanks.....yes I'm a hoarder.

I've been saving it to make myself a tarp, but it seems I'm always busy with other stuff.