make your own sil.

[StrawHat]

....so I did foam brushed the underside of my diy tarp leaving the front side untreated. The heat of the midday sun sets up the sil fast so I did pretty much what Patches did, mixed it in small batches. I pressed the foam somewhat hard against the fabric to force the sil to sip through, and with my other hand on the other side countering it. Brushed one side and went back on the other side for second coating. I concentrated on the ridgeline and the upper half part coz I think thats the most critical. Im satisfied with the finish job, smooth and without drip marks. For the solvent I just used an ordinary paint thinner, the smell is gone after letting it dry for 24hrs. It rained this morning so I made a quick setup to test the tarp. I stayed inside it for about an hour to check for any leaks and there was none. I was happy but not fully satisfied coz it was just a light rain. A storm is coming in this weekend so we'll see how it performs.

[rubi red]

Thanks for comments..

Plan for Sat. morning
Larger bucket and more time to make sure all exposed.
Foam brush with any solution left in the bucket.

[rubi red]

It past the hose test this morning.

I like it.

[harrell79cj5]

In February of this year I made a 10X12 Camo tarp from DIY gear supply camo 1.1 oz ripstop and then sil'd it myself using about a 4:1 ratio. I have used it quite a few times, and through some rains with great results. This past weekend I was in a rain that started about 8pm and rained hard and steady all night long (with pretty good wind too). The tarp did great at holding the rain out on the body of the tarp, but about the middle of the night I woke up with water dripping on me! The ridgeline seam was pulled pretty tight and the ends were higher than the middle (side tieouts pull the center down). Either my ridgeline was leaking (I didnt seal it seperately just did it with the same mixture I sil'd the rest of the tarp with) or water was running down the underside of my ridgeline seam to the low point in the middle and dripping. The entire length of the ridgeline seam was wet on the underside. So I either need to seal my seam with a thicker (3:1) mixture or put some kind of drip cords on my ends. I have to do some testing during the day when I can see it better. Anyone else have similar problems?

I did some more hose testing (read: full blast at 6") on the ridgeline and found that water was coming through and then running down and dripping in the center. I mixed up a batch of 3:1 ratio sil/mineral spirits and put it on the ridgeline. pretty sure that fixed my problem. I didnt have any problems for awhile but it had rained really hard all night (tropical depression), which will find any way through if possible. Just wanted to post for others that have sil'd tarps, you may want to do some hard testing on the ridgeline if you havent already.

[JohnSawyer]

I dunked and kneaded my tarp, then wiped both sides down with a sil/mineral spirits dampened rag...

I haven't had any problems, but I did get 1/2 of a tube on an 8x10 tarp.

[egrant5329]

Well I am going to give the DIY silicone a try just to see if I can do it. It seems like it has to be a terribly messy project, but I thought I would try it anyway.

I threw this tarp together out of some cheap 1.1 oz nylon that I ordered while ordering supplies for another project. It measures 130" x 72" which is bigger than the MacCat Micro and weighs 174gm or 6.15oz. I'll be curious to see what the weight ends up being when it dries.

Wish me luck!
Ed

[egrant5329]

Well today I made the I applied the silicone to the nylon. I took 1 tube el' cheapo Walmart silicone and added it to ~3/4 a bottle of mineral spirits. I shook the devil out of it and let it set for 3 days (shaking it occasionally). This made a nearly homogenous mixture with no clumps.

To apply it, I poured it into a small bucket and dunked and massaged the tarp into it. After a few minutes of working it around, I pulled it out and hung it up.

There were a few places that didn't get covered, so I used a foam brush to work some of the excess down the material. This process also coated/saturated the few areas that didn't get covered when soaking it.

I almost messed up because I had to move it before it dried completely. My garage was about 35 degrees and after letting it set a few hours I moved it to our basement to finish drying. While moving it the tacky cloth stuck to itself and I almost couldn't get it apart. Fortunately it didn't hurt anything.

While it hasn't completely dried yet, it's close. I have attached a photo of the material coated. It's darker than the original now and seems more transparent.

All in all it wasn't real difficult, nor too messy, but it did have a horrible smell that reminded me of the old film developing solutions.

Total cost was ~$20 and a lot of time making the tarp. Next time I'll just buy a tarp, but this was fun and educational!

I'll add the weight when it is completely dried. I am guessing it is heavier than commercial nysil.

[Rain Man]

I shook the devil out of it and let it set for 3 days (shaking it occasionally).

My understanding is that this mixture will not last, but begins to congeal within a short while of being mixed. I've come back a day later and found it to be like Jello and useless. So, just be careful of thinking letting it set is good for it.

Glad it worked for you, though! I've found it a very handy way to re-do stuff sacks, backpacks, and the like.

Rain Man

.

[egrant5329]

The mineral spirits I purchased came in a plastic bottle with screw on lid and I mixed it in that bottle screwing the lid on tight. My end mixture was about like the thickness of Elmer's glue, perhaps a tad thicker.

I mixed it Friday afternoon and applied it today, so it lasted about 3 days without any problems. I assume as long as you keep the mineral spirits in and most of the air out it shouldn't set up.

[Frost]

It will still set up to some degree if left un-aggitated, even in a sealed container. What you'll get is a layer of goop on top of the liquid that is sort of a really springy, stretchy stuff sort of like the stretchy snot that used to be in the little gumball vending machines as a toy. Shaking it every 8 hours or so will keep it from doing that for quite some time though.

I used a 3 gallon metal bucket, and a drill with one of those huge paint stirring corkscrew thingamajigs to stir the bejesus out of it for a good 10 minutes. Let it set for about 15 minutes, then did it again, then dunked my tarp. It worked pretty well. Didn't see any chunks. I put the mixture back in the mineral spirits container afterwards, but within about 5 days, it was completely wrecked. I probably could have dropped some solvents back in there and rescued it, but I didn't bother.