Tarptent Preamble silpoly 1P+ floorless tent

Wow, this thread is more involved than I would have expected.  Two things:

1) The Preamble is just our way, both internally and externally, of celebrating 20 years.  It’s floorless because the first shelter I built for myself for the ’99 PCT thruhike was floorless and it worked for what I needed it to do.  Of course it isn’t right for everybody and of course it has limitations.  It’s also purple because the original one was purple.  Truthfully our team had to outvote me to do it in purple but then I thought why not. It’s a limited run and if it proves popular enough we can do another run in green if that’s what people want.

2) Silpoly.  Yes, we have been looking at silpoly for a few years but I was just never happy with the samples until recently.  The issue for me has always been excessive bias stretch which compared unfavorably to our silnylon. This stuff is much better that way and it’s silicone both sides so the tear strength is better than sil-pu though not as good as silnylon. It’s our job to properly reinforce.

-H

To see the original purple Tarptent:

https://www.tarptent.com/about/

https://www.tarptent.com/tarptent/

https://www.tarptent.com/pcthike/tarptent/ttphotos.html

The 2022 version looks like it has several improvements – besides silpoly.

— Rex

Yes, I miss Franco and his incredible photos of birds.  There was a recent post from him not so long ago.

1.1 oz silnylon, 6.6 is still on Thru-Hiker’s website:                                                                  http://thru-hiker.com/materials/coated.php    It is 1.4 oz finished, though.

A few years ago, Richard Nisley tested some of TT’s newer silpoly along with some other fabrics that I sent him.  Agree that Henry has his own suppliers, as do Lightheart and other small businesses.  So just because the specs are the same does not mean a fabric will perform as well.  MYOGers have limited options, and quality can vary from roll to roll.  So we have to test our own purchases ourselves, or find someone willing to do it.  It is bit of a crapshoot, but we get to build to suit, as the saying goes.

Or you can just buy from TT or others if the tent is close enough to what you want.

I wish I could get my hands on some quality 20D silpoly (pure silicone both sides, no PU garbage).

If TT were to make tents with an olive green 20D silpoly sales would go through the stratosphere, especially in the more populous European market where earth tone stealth colors are more in demand. I could see Henry continuing to use 30D nylon 6.6 with the more involved poled models such as the Rainbow and Moment DW. Perhaps 20D silpoly would work best with the simpler designs like the Notch or Protrail. Mere speculation mind you. I can only imagine what the demand would be for an olive green silpoly Notch. It would be hard to keep them in stock.

Yes, I miss Franco and his incredible photos of birds.

He still posts pretty regularly on backpacker basecamp.  There is a pinned topic in the Trailhead Register calld Birds where he frequently posts his amazing photos.

He still posts pretty regularly on backpacker basecamp.  There is a pinned topic in the Trailhead Register called Birds where he frequently posts his amazing photos.

Yes he does, and his photos are excellent. Unfortunately, backpackers basecamp is more a political forum with a few backpacking topics, than the reverse. Meh. The good new is, however, you don’t see the political forum unless you’re registered there.

That’s how it used to be here, a political forum you could only see if you were registered.  Franco posted on that sometimes.

Monte – maybe look at what Yama uses – 20D silpoly, 1.1 ounce before coating. (I’m assuming it’s sil on both sides, I think Gen would mention if PU was used?)

Our Swiftline has been through the ringer and I definitely don’t baby it. The cat cuts are on the dramatic side and the reinforcements are pretty stout, so that all contributes something. But the fabric hasn’t presented an issue.

Thanks Chris, but I was referring to silpoly by the yard for my MYOG projects. I have no doubt however that Gen at Yama is using a quality silpoly for his shelters. He’s not slumming in any area and Gen thoroughly reinforces all of his tieouts.

I like the option Trekkertent has on most of their tents where you can choose between 20D silpoly or 40D silnylon. They build for the Scottish Highlands and areas of northern Europe where ferocious winds are common. Maybe 40D is overkill and 30D silnylon 6.6 would be good enough. Anyway, a smaller cottage company like Trekkertent can offer more custom options, whereas a bigger outfit like Tarptent does  “runs” in more of a true factory process, so quickly adapting and offering a 20D silpoly or 30D silnylon option would be harder. Probably wouldn’t fit into TT’s business model. Too bad though. That way people who tend to backpack in climates and conditions that are likely more fair and calm could choose a lighter 20D silpoly with less sag and water retention, yet if they wanted something bomber they could also choose the 30D silnylon option.

Monte, re: “I wish I could get my hands on some quality 20D silpoly (pure silicone both sides, no PU garbage).”

You lost me. RBTR sells a 20 denier silpoly in many colors.  Don’t see anything in the specs about PU.  If I’ve missed something, please tell me.  Thanks.

Sam, as you can see in RSBTR’s description of their 20D silpoly, it clearly states that it’s coated with “Silicone/PU ” (first paragraph, second sentence) The coating is a mix of both and not PU on one side and silicone on the other. Definitely NOT pure silicone and that’s why it’s weaker.

https://ripstopbytheroll.com/collections/waterproof-polyester-fabric/products/1-1-oz-silpoly

Monty,  my point was that RBTR’s silpoly is 20 denier; but your concern seems to be that the RBTR sil/poly silicone coating  contains some polyurethane, and is therefore weaker.  After researching RBTR’s website, I also found that the sil/PU is a “blend” (their word) of silicone and polyurethane, and even their silnylon is coated with such a blend (but not the “mountain” silnylon, which is only silicone coated.)

I’ve wondered how silicone and polyurethane coats can be blended, because the coatings do not appear to be compatible in normal uses, such as seam-sealing.  But suspect this may be a proprietary matter for RBTR, so would be interested in any information showing that the use of the polyurethane in their blend weakens either the fabric or the coatings.

The only advantage of pure silicone coatings I’ve observed is that they allow the fabric to remain more flexible, a real advantage in maintaining a taut, and therefore more wind resistant canopy.  Unfortunately, with sil-coated nylon, the nylon fabric can bring with it other weaknesses, like the inability to maintain its shape in wet weather.  And going back a decade to two, there were a number of silnylons on the fabric market that exhibited poor waterproofness.  So do not believe that a silicone coating alone is necessarily superior to polyurethane.

At any rate, not sure that a small amount of polyurethane in RBTR’s sil/poly is any reason to make the fabric weaker.  Granted, pure PU coats on a thin 10 denier PU nylon, and heavy coats (“PU 4000”) on RBTR’s polyester, can seriously weaken the fabric, especially over time.  I’ve observed this effect a number of times.  But am wondering what evidence we have that this is so with RBTR’s “blend.”  Dutchware also has sil-coated polyesters, but they seem  even more mum about specifics.  I did learn from several tests that Stephen Seeber was kind enough to do that the RBTR 20D silpoly maintains a significantly higher HH after simulated aging than the Dutchware.  And after purchasing some silpoly from a couple European firms, found that they were the RBTR product, but this does not include the 30D, 45 gm sil/poly sold be Extrem Textil.

So the question you raise about the “blend” is a concern, but am not ready to discount RBTR’s 20 D sil-poly at this point.  Any information you could provide about this would be greatly appreciated.  Thanks.

interested in any information showing that the use of the polyurethane in their blend weakens either the fabric or the coatings.
A good question.
I suspect the answer may be that even in a blend the PU is a bit ‘harder’ than a silicone, so it focuses the tear force onto a single thread.

The only advantage of pure silicone coatings I’ve observed is that they allow the fabric to remain more flexible, a real advantage in maintaining a taut, and therefore more wind resistant canopy.
Utterly so.

Unfortunately, with sil-coated nylon, the nylon fabric can bring with it other weaknesses, like the inability to maintain its shape in wet weather.
Ah – not so fast. It depends a bit on the quality of the silicone. If the threads are properly encapsulated by the silicone not much water can get in. (‘not much ‘ is NOT ‘none’)

> And going back a decade to two, there were a number of silnylons on the fabric market that exhibited poor waterproofness.
Yeah, the coating companies went a bit too far. The consumer paid.

Mind you, a PU-coated fabric might make a good groundsheet: it would be more waterproof.

Cheers

I know several people who have purchased ZPacks Duplex tents to use solo, because they wanted both the space to spread out their gear AND the weight savings of DCF.  While a bit more fiddly, I could see a tent like this fulfilling a similar niche at less than a third the price.  If I didn’t already own a Durston XMid-1 I’d be very tempted to acquire one.  Heck, at $199, I’m going to have to try really hard to resist my Gear Acquisition Syndrome just to get one and play with it.

I also am doing some trips with my 10 year old grandson where I’m obviously the pack mule, and I can see this being a lightweight and budget friendly option.

The lack of a floor doesn’t bother me.  Lots of pyramid tarps are sold by MLD and others without a floor, so why is it suddenly a problem for the Preamble?

C’mon Jeff.  Go for it.  You know ya want to.  Pull the trigger.

Am I helping ?    ~RL

You’re killing me, Regis!  lol

Roger, I know you have a professional background with fabrics, but I have stuck numerous silnylons in embroidery loops and subjected them to foul weather until blue in the face.  Even built a prototype canopy and put it outside in nasty weather, although under a deck.  It did not collapse, but became flaccid and unsteady, and probably would have collapsed up on the ridges.  They all expand, wrinkle, and become unreliable to hold a tent taut and steady in a serious blow.  So that’s why I’m finally looking for alternatives despite the fact that ‘polyester’ can mean anything and is a total crapshoot.  I have had some luck with boosting the waterproofness on paraglider nylon which weighs in at under one ounce, but supports paragliders high up in the air.  Interestingly, the gliders are very tightly woven nylon and are lightly coated with the dreaded polyurethane.

I think your tunnels, because they are tensioned and shockcorded at the downwind end are the best way to stabilize silnylon tents; but they are not the type of tent I want to build that is self-supporting and thus lowers tension on stakes whose primary function is to anchor the tent, but not so needed to hold it up.  Am content to agree to disagree, though.  Especially because you are spot on about most everything else.

I think the advantage of polyester is that it doesn’t stretch as much as nylon when it gets wet and/or cold

If I set up my nylon tent taut, in the morning it will be loose.  A polyester tent will remain more taut.

But, all you have to do is re-tighten tent stake guys and your nylon tent is tight again.  Not a huge deal.

I’m happy with my RSBTR polyester mid.  Next time, I might just use silnylon because it would be a couple ounces lighter.

How interesting.  If you type RSBTR it get’s replaced by a link to RSBTR.  Not so if you type RBTR.

RSBTR

silnylon is 0.77 oz/yd2, silpoly is 0.93 oz/yd2.

maybe I need 12 yd2 for a mid

so I’d save 1.9 ounces to do it in silnylon.  Not a lot, but something…

Has anyone weighed their silnylon fly after a good rain?  Perhaps the ~2oz initial penalty from silpoly is a moot point.  I’m in NorCal.  Rain?  What’s that?  ~RL

Hi Sam

I have to agree with you: that what fabric you can use will depend a lot on what tent design your are building. No argument.

I don’t see any slack after rain on my tunnels, but that is obviously a feature of the strong bungee cords at the lee end.

Cheers

I weighed my silpoly tent after it got wet in the rain.  It weighed quite a few ounces more.  I forget now.

I think silnylon would have about the same additional weight as silpoly.  It’s a property of the silicone and how many drops stay on the surface.

Copy.  Noted.  My layman novice approach as a weekday warrior who spends more time fighting off ticks, scratching from poison oak and throwing rocks at the sun, is to have silpoly on hand if only for shade and the UV factor, as I’m told.  Dunno.  My hang up.  ~RL

Hi Roger,

Re:  “I have to agree with you …”  On reading your reply post, I was stunned.  In addition to your being “spot on,” I should also have mentioned the help you have given me over the years.

BPL’s slip seems to be showing a bit with the blitheness of some posts lately.  Could this be symptomatic of the mis and dis info that floods mainstream social media?   So I also appreciate your setting us straight from time to time.

Should you perchance come across a silnylon that remains relatively stable in stormy weather, please send me a 12″ square, or some sourcing info if you’re willing, and I’ll test a square in my embroidery loops exposed to the next storm.  We get some really good ones, being located between the White Mountains and the ocean off the Maine coast.  If I’m wrong, I’ll eat my hat.  But only the summer hat, not the winter hat that is heavy and would be hard to chomp on.

And thanks for posting the links on the other current thread to your articles on sleeping mats/pads.  I’ll bookmark and save them for future reference.