Silpoly 20Dx50D floor material?

I would be interested. Most 30D silnylons I have bought recently for floors have weighed 1.5-1.6 oz/sq yd or more. Having a fabric option that is the same weight or lighter with a good HH would be nice. I think with one side PU-coated, it might make the floor less slippery too.

I thing the 1.5 or 1.6oz.yd material with a good HH would be interesting to the DIY crowd.

Silnylon always leaks out of the box, so to speak. Body weight is enough to do it on anything but loam/duff. I ended up recoating the whole floor with a 10:1 mix to get a decent floor, added about about .4-.5oz/yd.

Should work fine. Would need to be cheaper than $12.00/yd. I would be more interested in puncture resistance as opposed to abrasion resistance. Probably more a byproduct of weave density and fabric type(nylon, poly, etc).

Ryan

I definitely agree with what's been said. Poly on the inside would make slipperiness lessof an issue and the low stretch of polyester on a floor would be neither here nor there. I'm still more interested though in getting a waterproof nylon or polyester in the 1 oz range. The membrane nylone sounds pretty close, but waterproofness maybe leaves something to be desired. And color selection.

Right on. The current silnylon/silpoly is geared towards tarp/shelter walls where you don't need as high an HH. You could use it as-is for a floor, but it would pass some moisture under the pressure of bodyweight.

It would be in the neighborhood of $8 /yd I believe. That's one reason for going with the PU one side. It's much easier to process and brings the cost down. I would think the thicker coating can only help the puncture resistance.

Kyle, I am curious about the "20Dx50D" construction.

Does this mean you have 20D fibers in one direction and 50D fibers in the perpendicular direction?

What is the effect of this on things like puncture and abrasion resistance? How does it compare to your typical 30D silnylon?

Why would 20Dx50D be better than, for example, 30Dx30D?

Sorry, that's a lot of questions

No problem John. What I mean by 20Dx50D is that the base fabric yarn both warp and weft is 20D while the ripstop grid is a thicker 50D yarn. Your typical 20D or 30D ripstop fabric uses the same yarn throughout for both the base warp/weft threads and the ripstop grid.

The "cross-denier" or whatever you like to call it increases the abrasion resistance, strengthens the fabric, and reduces stretch for very little weight penalty. I'm inclined to say it doesn't do a whole lot to puncture resistance.

I've only tested the 20Dx50D on the silpoly and don't have a 30Dx30D from the same manufacturer to make an apples to apples comparison. However, I would estimate that the 20Dx50D would have similar strength and abrasion resistance but weigh a little less than the 30Dx30D. Certainly compared to the 20Dx20D silpoly it's significantly stronger and more abrasion resistant for minimal weight increase (+0.03 oz/sq yd).

Thanks for the reply, Kyle. I might be making another inner tent soon. I had assumed the SilPoly would be too thin, but it sounds like it might be fine. The higher HH would be nice though

We are having a floor version of the 20D silpoly that should be done in a couple weeks. Sil one side, PU coated other side. 3500 mm HH is the target.

On another note, would anyone consider using a higher denier floor for puncture and abrasion resistance, something like 100D, coated to around the same HH?

Kyle,

Wish I would have known about this! I have some HyperD 300 on the way I'm planning to use for a tent floor.

I'd prefer the 100D. Maybe even somewhere between 100 and 200. My philosophy is I'd rather have a thicker/stronger/heavier floor than have to carry a ground sheet. I think the lightweight 20×50 is a good idea, but probably still not thick enough to warrant upgrading from regular 20D ripstop. I'd still want a groudsheet for it.

I think it would depend on the weight for 100D. I personally do not see any reason to go above a good 30D silnylon for a floor (1.5 – 1.65 oz/sq yd); the material has worked well for me with no groundsheet, and I would not bother using something heavier.

Agree with John. Everyone thinks Tyvek is overkill at 1.8oz/yd and imagine the 100d would be well north of that. Digging that high HH silpoly though. Think I'm going to try it for shelters instead if you bring it to market.

If you're taking requests, some woven Dyneema in the 3oz range would be nice.

Ryan

Thanks for the feedback everyone I appreciate it. I'll have to sit down and weigh all the options.

@Ryan – On the high HH silpoly, we should have that in about 10 days. Would you plan on taping the PU side or using a sealant?

Kyle,

I would most likely use sealant. It's easy to use, cheap, and I can buy it locally.

Ryan

Actually, plain old SilNylon at 1.3oz/yd is stronger. I use a coating of mineral spirits and silicone caulk to achieve arond a 4000 – 5000 mm HH. It adds about .2-.3oz/yd for the same or better hydrostatic head and is basically a stronger material. Check it yourself. Poly is only cheap. If you tape off about 6" above the seams/floor all the way around, you end up with a watertight bathtub floor. Just remember to seal both sides of the floor and let it sit in a hot/dry area for a few days to cure thoroughly. The finished product is ~1.6oz/yd and VERY water resistant. The caulk is thin enough that it does NOT peel and it has the advantage of making a nice floor, ie, not slippery.

Basically, I see no use for poly at the same strength as nylon, because it will always be heavier. I am looking for LIGHT WEIGHT.

Maybe you've posted it before, James, but could you specify the proportions of silicon caulk and mineral spirits you use for floor coating?

Kyle,
The floor is one place where nylon is well suited because the sag is not the problem it is on the canopy. The higher strength, elasticity and abrasion resistance of nylon is also a plus on the floor. And with the floor not being very exposed to sunlight, the UV performance of polyester is not that much of a plus there. With the floor kept taut by the tent design, I find that the lubricity of the silnylon is much less of an annoyance.

A 15D poly with the lightest high HH coating would be ideal for canopies if closer to one oz/sq/yd. Eliminating the sag issue without need for a complex design to correct for sag would enable a permanently taut canopy with all the advantages of same and much easier tent design and building. And the bias stretch from the warp and weft should still allow some give when subjected to high wind forces. At least that is what I found when working with the heavier Epic Malibu formerly used by BD. A great fabric, but just too heavy for really light shelters. The water resistance has been known to fail badly above 1500mm also.

Until then, will be sticking with silnylon for the floors, and for the canopies with a design to address the sag. The Terra Nova 3000mm 1.16 osy seems a good choice for ultra light floors, but very expensive. The Extrem Textil 20D silnylon at about the same weight looks good for canopies, costs much less to use, and I hope to see some tests from Richard soon – will be sending him some samples this week.

But if you can beat either of them, with HH confirmed by Richard or other reliable source, that would certainly provide better choices for MYOGers, I think.

The idea with the 20Dx50D silpoly floor was to have something with about the same abrasion resistance and tear strength as 30D silnylon, but slightly less weight for the same HH. I think it's possible to hit 4000-5000mm HH south of 1.6 oz/sq yd with the 20Dx50D poly. How close the two would be in strength would remain to be seen. Would also depend on the specific silnylon you're comparing it to I'd think.

Thanks Sam. Agreed on poly vs nylon comments with regards to floor application. At present we only do the 20Dx50D in poly, so that was just default choice.

The next gen of the Membrane sil will most likely be a 15D poly or taffeta nylon. There are pros/cons to each. The 15D silpoly is attractive for less water absorption and lower stretch, but could be a bit scary as a shelter fabric given the lower strength of poly and general thinness of 15D. The reverse could be said for/against the nylon taffeta compared to poly. Nylon taffeta would be stronger, but it's going to have more stretch. The first Membrane sil we did was actually not bad on stretch for a 15D nylon, but could have been better on WP for use in tarps/shelters.

I noticed the new material is in:

http://ripstopbytheroll.com/collections/silpoly-pu4000

Listed specs:

1.4 oz/sq yd
4000mm HH

I bought some – figured I would try it out for a floor. We'll see how it works out.

Edit: fabric arrived already. Just going by the listed fabric width, the length I ordered, and the total weight, it weighs about 1.5 oz/sq yd. It actually seems a lot tougher than the normal SilPoly

"Everyone thinks Tyvek is overkill at 1.8oz/yd"

I don't bother carrying a puncture repair kit for the mattress any more since I've been using Tyvek for my tent floors. That represents a weight (& time/aggravation) saving over thin nylon + repair kit for a 3yd floor.

I've been using 30D silnylon floors for a few years now. I've never gotten a puncture in a sleeping pad when using a floor, until very recently, when I got multiple small punctures on the first night of a 4-night trip. I was only able to find and patch one pinhole, and pretty much slept on a slowly deflating pad for the rest of the trip (which actually was not that bad – I slept surprisingly well).

Since then, I've been wondering if a more durable floor material would have prevented the issue. And I'm not sure that it would have. These pinholes were made by some very small sharp things – I'm guessing needles that had broken off of a pine cone. The bottom of my sleeping pad is already 50D, so would the Tyvek have helped?

I am currently thinking only a small bit of foam under the sleeping pad would have prevented the pinholes, and that maybe a section of 1/8'' foam would be weight well spent (adding insulation, some padding, and puncture protection). A 30D floor + section of 1/8'' foam would probably weigh similar to a full Tyvek floor. And if I use a foam sleeping pad, then I can just leave the 1/8'' foam at home.

Let me know what you think John. The weight discrepancy could be because we give a few inches extra over what you order.