Seam sealing RBTR silpoly

[squidbilly]

I plan on using my Silpoly to give my first go at making a tarp. Since that is the case, I plan on waiting a little bit longer while others are testing out what, if any sealants work on this material. If there doesn't seem to be a great solution for sealing, I will probably try my hand at a bound ridgeline instead of a flat-felled/french seam.

The bound ridgeline might be the way to go with these new materials: Silpoly and Membrane Sil. You could always mix your own DIY silicone sealer and paint the grosgrain if you had to.

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.

[Titaniumpyro]

Ok so the Acetic acid cured Silicone I is a no go. It peels off too.
The best bond I can get is with Silnet after wiping the fabric down with odorless mineral spirits and letting it dry.
squidbilly, what are your thoughts on the uv resistance of the loctite product?
I am tempted to try loctite's silicone before making a final decision.
Kyle, can you provide us with some technical data on the coating they are using? Perhaps it is a different cure silicone and we need to be in the same family to get it to bond?

[Mouseskowitz]

If you go with a grosgrain ridge line don't try my good ides of putting ties in the middle for your internal pole mod. They work as wicks and drip water on you in the rain. Threads like this keep reminding me I need to seam seal it before I hang in the rain again.

[ripstopbytheroll]

OK so as of 3:35 am EST, I now have a clear picture of why some are reporting issues with the seam sealing. It turns out that one side of the silpoly was coated with a 90/10 sil/PU mix as opposed to 100% silicone. I have been working with the manufacturer on different coating processes for a while now and sil/PU is one that I've been testing with good results. Although I may use this in future lots, this particular lot was not supposed to get any of the new sauce, but it appears it did.

Like I said, the sil/PU in and of itself is not a bad thing at all. To give you a quick backstory, a lot of mills overseas are starting to come under increased environmental regulations, which is forcing me to look at other ways of doing the coating. A lot of mills in the US are already using a sil/PU coating. For example the Intruder Multicam silnylon uses a sil/PU coating. You can also go out and see that some of the best cottage vendors in the business use silnylon that is actually a sil/PU mix.

So that's my elevator pitch for sil/PU. Now what to do about the problem at hand. I think we should start by trying to find the pure silicone side of the material, put it facing out, then sealing it with Silnet or any other 100% silicone sealant. I can't completely guarantee that will work, but in theory it seems to make sense. It will be hard to tell, but the pure silicone side will be the shinier of the two sides. If someone is feeling scientific and has access to several different sealants, it would be a good idea to try them all again on EACH side of a scrap piece of material. Some have already posted multiple trials, but if you weren't paying attention to the side you were using, you could've gotten a false negative for one or more sealants. Second option would be to look for some type of home mix short of 100% silicone that will work if you already have the sil/PU side facing out and can't pitch the tarp with the other side out. Given the fact that other tarp manufacturers are already using sil/PU tarp materials, I have to think that there is a mix that will work here. Knowing the ratio of sil/PU should help narrow the search.

I do sincerely apologize for all the trouble on seam sealing. Hope this information helps get everything back on the right track. Talk to everyone tomorrow.

[SimonMc]

This may be of use http://www.seatosummit.com.au/produc...ultra-seamsil/.

[squidbilly]

This may be of use http://www.seatosummit.com.au/produc...ultra-seamsil/.

Thank you SimonMc! If what Kyle says is true, then that might be the stuff to use.

[squidbilly]

OK so as of 3:35 am EST, I now have a clear picture of why some are reporting issues with the seam sealing. It turns out that one side of the silpoly was coated with a 90/10 sil/PU mix as opposed to 100% silicone. I have been working with the manufacturer on different coating processes for a while now and sil/PU is one that I've been testing with good results. Although I may use this in future lots, this particular lot was not supposed to get any of the new sauce, but it appears it did.

Like I said, the sil/PU in and of itself is not a bad thing at all. To give you a quick backstory, a lot of mills overseas are starting to come under increased environmental regulations, which is forcing me to look at other ways of doing the coating. A lot of mills in the US are already using a sil/PU coating. For example the Intruder Multicam silnylon uses a sil/PU coating. You can also go out and see that some of the best cottage vendors in the business use silnylon that is actually a sil/PU mix.

So that's my elevator pitch for sil/PU. Now what to do about the problem at hand. I think we should start by trying to find the pure silicone side of the material, put it facing out, then sealing it with Silnet or any other 100% silicone sealant. I can't completely guarantee that will work, but in theory it seems to make sense. It will be hard to tell, but the pure silicone side will be the shinier of the two sides. If someone is feeling scientific and has access to several different sealants, it would be a good idea to try them all again on EACH side of a scrap piece of material. Some have already posted multiple trials, but if you weren't paying attention to the side you were using, you could've gotten a false negative for one or more sealants. Second option would be to look for some type of home mix short of 100% silicone that will work if you already have the sil/PU side facing out and can't pitch the tarp with the other side out. Given the fact that other tarp manufacturers are already using sil/PU tarp materials, I have to think that there is a mix that will work here. Knowing the ratio of sil/PU should help narrow the search.

I do sincerely apologize for all the trouble on seam sealing. Hope this information helps get everything back on the right track. Talk to everyone tomorrow.

So, on the Membrane Sil, the shiny side is the pure silicone side? I put the matte side out as suggested. That would explain why the Silnet didn't stick well.

I honestly couldn't tell a difference on the green tea colored Silpoly.

[Wanderlost]

Now what to do about the problem at hand. I think we should start by trying to find the pure silicone side of the material, put it facing out, then sealing it with Silnet or any other 100% silicone sealant. I can't completely guarantee that will work, but in theory it seems to make sense. It will be hard to tell, but the pure silicone side will be the shinier of the two sides. If someone is feeling scientific and has access to several different sealants, it would be a good idea to try them all again on EACH side of a scrap piece of material. Some have already posted multiple trials, but if you weren't paying attention to the side you were using, you could've gotten a false negative for one or more sealants. Second option would be to look for some type of home mix short of 100% silicone that will work if you already have the sil/PU side facing out and can't pitch the tarp with the other side out. Given the fact that other tarp manufacturers are already using sil/PU tarp materials, I have to think that there is a mix that will work here. Knowing the ratio of sil/PU should help narrow the search.

I do sincerely apologize for all the trouble on seam sealing. Hope this information helps get everything back on the right track. Talk to everyone tomorrow.

Doh! Your timing is ironic. I literally just cut out the pattern for an asym tarp with the shiny side down as suggested. Oh Well! Luckily, it's one piece of fabric so there's no ridgeline seam to leak.

[Titaniumpyro]

Kyle, thanks so much for the update. SimonMc may have given us the answer. I sure wish I could find a store nearby that carries it so I could test it today.
However on all of my tests, I have tried both sides of the fabric and the results have been the same.
However I have another set going now to specifically test this.
Anyone have the sea to summit product and can test it? It may be a few days before I can get my hands on some.

[ripstopbytheroll]

So, on the Membrane Sil, the shiny side is the pure silicone side? I put the matte side out as suggested. That would explain why the Silnet didn't stick well.

I honestly couldn't tell a difference on the green tea colored Silpoly.

No I'm just talking about the silpoly. The Membrane is made at a completely separate mill. Will report back when I know more about that situation.