Ecopak EPL/EPX Ultraweave

Apologies for the further thread drift. This is still on the construction question and has little to do with the ultraweave fabrics that are the topic oat hand.

This video shows the external binding construction of the Zoro well. It doesn’t look weird. I’m surprised more pack manufacturers don’t use this strategy. This link jumps to the relevant portion of the video, as does the embedded video below.

As for testing .. we sent out about 20 tester packs. They ranged from pure backpacking packs, to packs used on packraft stone sheep hunts, archery Dall sheep hunts in the chugach .. elk hunting , etc you name it. No issues of note. The EPLX400 is very nice as well. Frankly, I am surprised by how much Ultra is winning in the sales because excluding Ultra, I feel the EPLX400 packs are the nicest / best looking packs we have ever offered .. but the Ultra is a step above.

As for binding … I hate it .. but our packs can be very high stress,  and we have to be able to standardize stuff pretty well for all sewers . Extra thinking takes extra time and means less gear. Never had any sort of failure .. and honestly , while seam sealing is a PITA ( I really never do it .. and sometimes get a smidge of water but never anything that changes a trip or is more than a minor minor inconvenience) .. we will err on the side of not letting you down on reliability.

Taping .. we tried a couple … due to curves .. we would have to add a lot of time to each pack for it to be taped. I mean a lot.

At the end of the day, I feel we frustrate many of you , because we don’t relentlessly attack the last couple ounces and perhaps trade the last couple ounces for long term, top end, reliability. Remember many of our customers hop on bush planes and get dropped off .. on a many, many days walk from anywhere. We err on the reliability side. I know customers that have been stuck in the bush for 10 days longer than planned due to weather. In that case, your tent and pack .. you should be very confident in.

Guessing you are from Seek Outside Kevin – I definitely have never worried about reliability issues with any of your packs ( did a 9 day solo trip with one in Denali NP – they don’t believe in making trails there ). Overall the pack was great but my main issue was that once water got in ( which it did since it rained for the first 4 days straight ) it was of course difficult to get out given that the fabric is waterproof. I ended up dumping water out at sundown each evening ( sundown being 9pm in September ) which was relatively easy but it was a pain to have every single item double bagged with either trashbags or doggy bags just to make sure it didn’t get soaked. And of course by the end of the day the pack was taking on extra weight due to the water at the bottom.

Realistically I don’t personally care if the last couple ounces are eliminated since I am already carrying a big load hauling pack – it’s just more about the reliability / usability factor.  I know for example you guys moved on for the side pouches and top pouches to using a water resistant YKK zip vs the normal ones so obviously there’s demand from your customers for better waterproofing. Adding on flaps over those zippers would for sure add even more weight but be a good way to improve that even further ( similar to how most tents do ). And on the small stuff like that I can’t imagine seam binding with webbing is nearly as important given that they’re just small accessory pouches.

Anyways in summary it might be interesting if you gave the option to have customized packs skip the seam binding in places where its doable – that would still allow you to have the majority of your staff doing things the way they are used to and keep production at high capacity. The website also does market the packs as waterproof (it even says you do NOT need to separately bag your items inside) which you might want to amend or update – if someone had to spend 10 extra days in the bush and ended up with their down items getting soaked through that could be a pretty significant safety hazard. On the above trip I knew I would be crossing some pretty major rivers so I had everything extra double bagged just in case I had to dump the pack but if I did not do that and packed my sleeping materials at the bottom of the pack like I normally do then it could have really ruined my entire trip. Alaska can get pretty chilly at night – even in September.

You could of course just use a DCF pack liner from Zpacks or nyloflume pack liner to stuff everything in – which you probably are doing anyways. Sure you will still have to empty the bag when water gets in. But, how much water did you get inside the pack? tablespoon or more or less? Just curious.

I swam across a tidal lagoon once, pushing my HMG 3400 ahead of me as I went. I was probably in the water about 8 minutes is my guess. The HMG packs are factory taped inside, but the effect is not 100% sealing. I ended up with about a 1/4 cup of water in the pack, so not enough to worry about.

The way the inside of my pack gets wet is from packing in the rain and putting wet items inside. That is nearly impossible to avoid.

MLD updated their Fabric Mojo page.

Enjoyed reading every word of the MLD Fabric Mojo page.  If you can’t trust MLD, who can you trust?

MLD states that the Ultra 200 body with  ULTRA 400 back panel is their solution to lightest possible pack with full integrity. Mentioning Ultra 100 requiring reinforcements.

Anyone have any thoughts to this? Ultra400 seems extremely robust for a back panel. I would hope the Ultra200 would be suitable for the entire pack. Is there a certain reasoning? Maybe to add extra strength for the shoulder strap attachment points? This area often sees additional reinforcement patches from other manufacturers.

I recall Ron mentioning the shoulder strap attachment point as a reason they are using Ultra400 for the back panel. Also the weight difference for a piece of fabric that small is negligible. I’m under the impression that MLD errs on the side of durability versus weight in most cases.

Cam “Swami” Honan says that each of his two DX210d MLD Burn’s lasted 8000 miles. Each one lasted 8000 miles that is. The problem he saw was the shoulder strap foam becoming thin after around 6000 miles.

While I think all these newer materials (Ultra 400/200 and what not) may last much longer in terms of fabric itself, the shoulder strap foam is going to give up sooner:-) And 6000 to 8000 miles is something no one has on their backpacks….usually you change the backpack much sooner because you saw something shinier or it didn’t fit you or whatever reason one uses to change their backpacks.

That said – I do have a Ultra 400/200 MLD Prophet and DX210d Wasabi Prophet and Burn:-)

The Ultra 400 forms  the one piece back and bottom with no seam at the bottom.   All around the shoudler straps  is all 400. We think the 400/200  pack body/pockets will last a very long time and because of the super strong 400 back we can easily cut off old shoulder straps and replace them farily easy when the foam finally loses support.

Good to know Ron! I would love to own an backpack for 8000 miles! That will be an awesome accomplishment!

Ron, that makes even more sense now that I remember your packs use one piece back/bottom. I used a dx210d wasabi Burn for many miles with little to no sign of wear.

Still hope we can connect in the future!

Hopefully taping the seams protects against delamination.  It seems once the lamination comes off the weave starts separating.  The 400 does not have as tight of a weave compared to the 200 and I would think is more prone to separating apart.

I’m giving it one more try with a  pack with taped seams. Hopefully it doesn’t turn into another delamination disaster. Challenge has specific requirements for construction that need to be followed.

Palante is using other material in the high stress areas with packs that incorporate Ultra fabrics.

Looking at the specs for the Ultra100 is making me wonder again if it is possible to do some sort of woven laminated fabric for tent walls – to be worth it the tradeoff might be going 100% UHMWPE for the face (thinking more of something like an Ultra75). Seems like that could get it down to similar weights to burlier fabrics used on mountaineering / 4 season shelters. I have never liked DCF purely because it has such an odd disparity between puncture resistance and abrasion.

I think what helps more than taping is folded seams. It’s hard to explain, but when you fold a seam and lay it flat, the stress is pulling all along that folded edge instead of just on the specific stitch points. That makes it less likely to delam because the stress is not focused on specific spots. Taped seams are also folded seams, so when we see these delaminating less it’s hard to say the cause but my experience is that the folding is the main thing that’s helping.

It actually makes sense that folding would help since it distributes stress, whereas it doesn’t make sense that taping helps because the tape is just slapped on top of the interior plastic layer where it seemingly doesn’t do anything to help that plastic layer stay adhered to the woven face fabric. I can’t think of how it would possibly work, whereas folding has an obvious way that it works.

I would think that taping over the seams would add back strength to the holes that the needle is making into the laminate and prevent the holes in the laminate from migrating or increasing. The needle hole is nothing more than a small tear in the lamination. A combination of both folding and taping seams can’t hurt. I had a pack with 400 that had a number of delaminations. The seams were not folded nor taped. The locations with the highest areas of stress delaminated, the weave of the fabric became elongated. The lamination appears to be a necessary ingredient to maintain the weave, but I don’t sew things so just my uneducated guess. I would not want it as a tent material either. I don’t know that it could stand up to the constant stress of stretching and then folding or rolling it up.

Me thinks its a lot of hype, a bunch of pack makers jumped on the band wagon (have to offer it if someone else is) and because its the new new everyone wants it.

How does Ultra 200 compare with Ultra 400?  There is a marginal savings in weight.  What is the tradeoff with that particular fabric for getting something a hair lighter?

Regarding taping the seams, I did a simple test with Ultra 400. I sewed scraps together with a normal straight stitch, a flat felled seam, and a top stitched straight seam (faux felled) that I then taped. Pulling on the opposing sides of the seam as hard as I could produced noticeable stitch elongation in the straight seam, less but still some in the felled seam, and essentially none in the taped seam.

I know this isn’t totally representative of what’s happening in a pack seam, but it seemed clear that the tape was taking some of the seam stress. I also understand that some complex pack designs can’t be taped.

@BPLwiia – I’m also curious about Ultra 200 vs 400, but maybe from the opposite direction. I’m mostly interested in the context of larger packs (for packrafting, etc). SWD and Seek Outside both use Ultra 400. While I appreciate a burly fabric, is the 400 overkill? According to Challenge’s own numbers, the 200 has better abrasion resistance than their (non-ultra) EPLX400 – which I’ve used, and feels pretty darn burly to me. But maybe the numbers don’t tell the whole story?

I’m looking at getting a SO 6,300 bag only in the Ultra 400 so we may have a similar context.  It would helpful to get someone’s thoughts about how the Ultra 400 and 200 compare who has had experience with both of them.

It is an interesting question whether the Ultra 400 is an overkill.

I doubt there is a huge difference between them – packs do not use a ton of fabric anyways so I bet there is not a huge weight difference. In a small frameless pack I would worry more about minimizing fabric weight but with a load hauler like Seek Outside the difference in comfort is probably fairly minimal.

I was talking to Challenge today and they said the delam issues that some people have seen are a combo of seam design (e.g. the Palante packs with delam issues were straight stitched) and the density of the weave in their fabric. They said Ultra 400 and 800 were a looser weave that was more prone to movement and delam, so they are going to be increasing that density (e.g. higher threadcount). Ultra 100 and 200 have always been higher threadcount so performance has been better there. Until the issues with 400 and 800 are sorted out, opting for 200 seems like a safer better. You still have off-the-charts durability in a tighter weave.

Good to know Dan!

Stuff like this is why I am glad I usually wait a bit before adopting the cutting edge…..as much as I would love a pack in Ultra right now X-Pac is still holding up great for me.

Does anybody know of a source that sells small quantities of Ultra? I have been meaning to add some crampon patches to a pair of rain pants and while some other fabric is probably lighter I would like to get some practice sewing this stuff.

RBTR has most variants of Ultra: https://ripstopbytheroll.com/pages/challenge-sailcloth-ultra-lineup