pack fabric

[Jerry Adams]

I made a pack out of dyneema composite fabric, I think it was 2.92 oz

It has a 50 D polyester layer outside and waterproof dyneema inside

It’s been working okay, except after several years, maybe 100 days of hiking, the waterproof layer inside is delaminating a bit – I can see holes through the fabric and my packed gear gets wet, but not too bad.

Where the waste belt is sewn to the pack, the stitches have pulled through the fabric.  (Because I pick up the pack while standing on the waste belt)

My previous pack was 200 D nylon which didn’t have those problems, but it wasn’t real waterproof after a while.  I was thinking the dyneema lining would be better.  With 200 D threads, I think the gap between them is bigger so it’s hard to get the PU coating to be perfect.

Maybe 210 D Robic would be better?  It’s supposed to have a better waterproof coating. 4.4 oz/yd2.

Maybe 100 D Robic?  I wonder if it’s strong enough.  Weighs 3.7 oz/yd2, not that much lighter

Maybe if I just had a reinforcing strip inside so there’s two layers of fabric to rip out.  Or quit stepping on waste belt when I pick up pack : )

[Brook / MtGL]

you can tape (and tape again) on the inside of the pack. I think that’s a considerable advantage of DCF. But e.g. 210D robic could be more durable outside but less waterproofness.

[Sam Farrington]

If you’re looking for an alternative to DCF, or DP for that matter, there is the robic as you mention, and a number of others from the usual sources.  I think you would benefit from first selecting the material that at least appears tough enough to survive abrasion and punctures, and order a yard, and then look for someone on BPL to check it for HH AFTER simulated aging; the last being key, as packs seem to take the most abuse.

The fact that alternatives to DCF will be heavier is not so important for a pack, because much less yardage is used for a pack than for a tent, where a difference of an oz/sq/yd makes a huge difference.  Remember when “Newton” posted about a pack, and many were surprised at how light the pack was given the fabric weight.  So contrary to much opinion, I don’t see DCF as a solution for improving packs.

What is needed is a pack that removes weight from the back and places it on the hips, specifically the bones called the iliac crests.   You can get a knee replacement; but not a back replacement.  The constant weight of a loaded pack on the back over time will do a lot more damage than just having a slightly heavier pack fabric.  Learned that the hard way.  Weight-wise, it is not the pack material that is the problem, it’s the pack’s contents.

OK, many are happy with frameless packs, or ones with super light carbon frames, and feel that they take weight off the back.  Unfortunately, that has not been my experience, and I’ve found that an hour-glass shaped frame with side-arms is the only thing that really works to place nearly all the weight on the hips, especially after many hours and days of trekking.  This involves a fair amount of alloy tubing; so have experimented with using Easton tent pole tubing.  As has Roger Caffin for ladder frames.  Getting the 5/8″ dia. tubing completely out of the picture has been the biggest weight saver for me, and getting all the weight onto the hips has been the biggest back saver.

Bending the tempered tent tubing can be a challenge, but one that has been overcome with the use of sand packed in the capped tube, a better quality Ridgid high radius bender, and Roger’s invention of his “Rollng Jenny.”  Heat is avoided, because it destroys the temper of the tube.  The result can be an internal frame of much lighter tubing that is still super light despite the use of metal.

So what I’m saying is that the use of DCF to shave a little bit off the pack material is not nearly as helpful as a slightly heavier internal frame pack that keeps the weight on the hips, and a slightly heavier fabric that keeps the water out and resists wear and tear.

[Jerry Adams]

Yeah, good point, a slightly lighter fabric won’t make that much difference because the total area of a pack is small.

I think I’ll try the Robic next.

The only fabric I’ve used that wasn’t strong enough was a lightweight silnylon.  As I remember, it was 1.9 oz/yd2.  It worked for a while but then started ripping.  A good experiment though…

I did a 200D oxford from owfinc.  That was strong enough but it started leaking after a while.  200D fibers are bigger, so there’s a bigger gap between fibers, so more prone to leaking.  Especially after it’s been used for a while.  I think.  Maybe the robic would be better because they say it has a thicker PU coating.  The 100D has smaller fibers, so smaller gaps, so easier to get a good PU coating?  hmmm….

I haven’t had a problem with frameless packs, but I’ve read with interest all the articles and posts about frames.  With low weight (~22 pounds max) and a stiff pack, it seems like the weight is carried okay on my hips and I don’t have major back soreness.

[Bonzo]

Sam nailed it: I couldn’t agree more with everything said in that post.  Do whatever is necessary to successfully transfer weight onto the hips, and save both your back and total weight elsewhere!  The fabric weight in my pack is the least of my concern; what I want that fabric to do is be a bombproof shell for the much more fragile fabrics and materials that make up the things inside my pack.  I think the lightest fabric in my pack is X-Pac VX21; the main body is twice that heavy, and some of the removable accessory pockets have 500- and 1000D linings for sharp-looking things.  I don’t worry over the weight of any of it, because that pack carries like a dream…and most of that perfect carriage is because of proper fitment, not pack weight.

[Brad Rogers]

I was never impressed with the laminated DCF pack fabric and much prefer the X-pac options for “waterproof” packs.  I really still think 210 Dyneema Grid is a great pack fabric though.

[Sam Farrington]

Gerry,

I think sometimes it is the quality of the coating more than the size and weight of the fiber; but not when you get to 500D Cordura or the like.  I could never get heavy Cordura to stay waterproof.

If the Robic is from RBTR, it might be interesting to see how they rate the HH of the 200D vs the 100D.

I kicked myself, because altho I made it clear that keeping weight off the back was personal to me, I probably should have added that for those whose pack designs work well to shift the weight to the hips, there is no reason to go into the side-arms, or even the full internal frame, to keep the weight on the hips.  Plus side-arms only work well if there is a method to control the snugness of the sidearms and thus keep the belt tight over the hips.  When I get the latest pack in progress done, I’ll do an OP and go into that in more detail.

[Sam Farrington]

Is the 210 Dyneema grid pack material the same cuben pack fabric that Zpacks was selling when it was still selling fabrics?  That was a bit to stiff for me.  Am not into pack baskets, altho they have a certain appeal.

[Jerry Adams]

No need to “kick yourself” Sam, your points were well made, thanks

I think a thread with contradictory opinions is good because people can see the different possibilities and choose what works for them.  Arguing to a conclusion where one side “wins” is an exercise in futility.

RSBTR doesn’t give any HH spec for either Robic

I’m not sure what spec is good for a pack.  HH is good for a tent or rain jacket.  On a pack, the coating is on the inside, so abrasion would be from stuff inside my pack.  That is much worse than a tent or rain jacket.  That’s unique to me.  Abrasion on the outside has never been an issue with any fabric I’ve used – I guess I’m careful setting my pack down and don’t run into sharp sticks or rocks.

Since the 210D weighs just a bit more than the 100D, I’ll probably use it.

We could argue about pockets?  I’m in the no external pockets camp.  A fairly lonely camp?  I like the outside of the pack to just be a plain bag.  Sewing on pockets weakens the pack and provides opportunity for water to enter.  My “pockets” are bags inside the pack to contain small items.  Any critical items like down are in a waterproof bag – belt and suspenders – in case any water gets into the pack.

 

 

 

 

[Bonzo]

We could argue about pockets?  I’m in the no external pockets camp.  A fairly lonely camp?  I like the outside of the pack to just be a plain bag.  Sewing on pockets weakens the pack and provides opportunity for water to enter.  My “pockets” are bags inside the pack to contain small items.  Any critical items like down are in a waterproof bag – belt and suspenders – in case any water gets into the pack.

I’m not a pocket fan, either.  The only two built-in pockets on my bag are two wand pockets on the lower corners; they’re reasonably narrow, so they don’t get caught on anything.  I have storage both inside and out in the detachable lid, and there’s a secondary pocket/bag that I can strap through the daisy chains if I need extra storage for things that are dirty, sharp, etc.  No mesh, no big stuff sack pockets, nothing to get snagged; just your typical 50L alpine sack.  Like you, I carry the important, immediate-use stuff in a quick-to-grab space inside the bag; usually, that’s the lid.  If I’m not carrying the lid (stripped-down, lighter-weight mode) I’ll keep it all in a light sack right at the top of the roll closure, or near the side zip.

[Brad Rogers]

I like water bottle pockets and a front stuff pocket, though I could often do without that.  Where do you store water bottles?  A shoulder strap pocket?

On a side note, McHale’s water bottle pockets are excellent and they are not sewn on  to the pack so if you want the waterproofs of no sewn on pockets but still want some water bottle pockets, that might be a source of inspiration.

[Bonzo]

Where do you store water bottles?

Usually inside the pack.  I normally don’t drink on the go; I just stop when I’m thirsty, take a break, grab a quick sip and move on.  I’ll drink more at lunch when the pack is actually off my back for awhile.  I also might grab a quick drink if I stop for an especially good photo, or to look at wildlife, or for whatever reason.  I guess I take a lot of stops, so I’ve never really gotten to wanting a water bottle outside of my pack; it’s also usually a lot of weight right out on the perimeter, and usually in a location that I don’t want it to be.

[Jerry Adams]

Bonzo, it’s just you and me.  I saw a picture of Ryan with a pocketless pack once.

I keep my water bottle inside, at the top.  It’s better insulated so cooler in the summer, doesn’t freeze in the winter.  Next to some food.  It’s just as easy to open the top of my pack as it is to open a pocket.

My classic Kelty pack had many external pockets.  (and a frame).  I finally gave it to the Goodwill.

[Brad Rogers]

I guess I only (generally) take my pack off for lunch so I couldn’t having to stop and take my pack off to drink water, but I do otherwise see the advantages to a very streamlined pack.

 

[Bonzo]

Bonzo, it’s just you and me.  I saw a picture of Ryan with a pocketless pack once.

We’re alone in the world, Jerry, but it’s okay.  Here’s some self-acceptance coaching from the master:

I keep my water bottle inside, at the top.  It’s better insulated so cooler in the summer, doesn’t freeze in the winter.  Next to some food.  It’s just as easy to open the top of my pack as it is to open a pocket.

Yep.  A little bit of shade keeps my water from turning into a greenhouse in the summer, and in the winter I don’t care how cold it gets as long as 1) it’s still water, and 2) the lid isn’t frozen to the bottle.

My classic Kelty pack had many external pockets.  (and a frame).  I finally gave it to the Goodwill.

I loved my Super Tioga.  Still have it, although I don’t carry it.  These days it hangs on a wall, full of some other classy throwback gear that I just don’t want to part with; too many good memories.

Interestingly enough, that pack isn’t really very heavy once you strip the frame from it, and the fabric on it saw rough use and it still looks remarkably new.

I guess I only (generally) take my pack off for lunch so I couldn’t having to stop and take my pack off to drink water, but I do otherwise see the advantages to a very streamlined pack.

Once I get mine fitted to whatever clothing I have on that day, it’s a no-brainer to get it back up and riding correctly.  I used to have incessant problems with that, but getting a correctly-fitted pack solved all of that.  It’s as easy as taking off and putting on a hat, now.

Streamlining has been the order of the day for me, lately; too many tight trails and snags have taught me some expensive lessons.

[Michael B]

I really like my frameless pack I made from 420 Robic. It came in around 500g, has nice stretchy back and side pockets, and fits my BV450 well. I use a trash bag liner because it is super easy and adds little weight. It also doubles as a sleeping pad pump.

the thing I didn’t know about when I bought the fabric but have come to love about it is its stretchy/springy nature. It seems to act like a suspension even though there is no frame, and seems to conform pretty well, and ride pretty well even though the padding I used for the straps and belt is quite thin. It almost conforms to my whole back, which you’d think would be kind of sweaty and uncomfortable, but I’ve not experienced that. When I am stepping, it has a sort of sprung bounciness that I think actually helps with the comfort on my shoulders. The 420 is NOTABLY tougher than the 210 Robic. 420 was a bear to cut through compared to the 210 when I cut the pattern. This leads me to believe it will hold up better structurally in the long run for only a small weight penalty. The one thing I do not like about it though, is its lack of stiffness makes packing the bag a little more difficult since it lacks the ability to stand on its own like many of the stiffer fabrics.

Robic is significantly cheaper than the Dyneema or DP products, for what I perceive to be no functional differences. I thought I’d get over the pack and make a new one, but I’ve been happy enough with the fabric that my next pack will be the same fabric, with just some of the features modified based on my experience with this one.

[Bonzo]

I think that if you get the measurements correct, you have more latitude in being able to remove the frame from a pack (if possible due to the design) and still have it carry well.

[Diane “Piper” Soini]

Maybe to lengthen the life of your pack, don’t step on the waist belt when picking it up.

[Jerry Adams]

I am developing the muscle memory to avoid doing that, stepping on strap when I pick up pack

Another one is don’t let the buckle hang down so that it gets smashed when I close the car door.  I think maybe that was at the end of the trip so wasn’t a big deal.  Putting a new one on back home isn’t too difficult

[Sam Farrington]

For a long time, I used Jansport packs, and they all had side pockets that fit the Nalgene quart bottles perfectly, so went with it.  When I got into building packs, not just modifying them,  thought of the Mountain Club frames used to carry supplies up to mountain huts.  They had all the weight strapped to the very top of the frame.  Since water is the heaviest item,  switched from cylindrical to short boxy shaped quart bottles, and put two of them side-by-side and top dead center standing upright in inner pockets just under the pack top.  On the right and  left of the bottles were narrow inner pockets  for smaller stuff.

Of course this had to be at least a 2/3 panel loader to zip down and get at the water bottles and other stuff.  Had gotten to like the panel loaders with the Jansports.  With water resistant zips and flap covers, they did not leak as often believed, and MYOG made it possible to build the pockets inside at the top.

But I finally realized that even packs without frames and side-arms are much more comfortable if they can rotate up and down with the hip belt while walking.  But putting most of the weight up top made such packs top heavy and tippy when the hips rotated.  So the bottles went to lower side pockets where they lowered the center of gravity.  So with or without side-arms,, all the more recent packs have had the bottles on the sides.  Not zip pockets, just tight cylindrical pockets with only lacing on the bottom so they can drain with leakage or rain.

The schemes for allowing the belts to rotate have varied from just the common one of slipping the belt though an envelope and held with velcro, to a recessed bolt that allowed full rotation.  (I found that the belt only had to rotate a little bit, and chucked the hardware, which also wore out too often).  But like an airplane propeller, they all rotated much better with the lowered center of gravity, which could be accomplished only with lowering the bottles.  The rotation point worked best just above hip level at the small of the back.

I’ve often had to bushwhack on long trips due to huge rockslides and such, and the side bottles have not been a problem, or even noticed.  Could be that is because the packs are not terribly wide, just wide enough to fit stuff sacks on top of each other.  So the bottles don’t get in the way or bump into things.

So I’ve gone almost full circle back to conventional designs, except that the next pack is going to have the side arms back, but with a lowered center of gravity.

Given the moderator’s love for pictures, here are a bunch of older side-arm packs, posed for a photo:

[Bonzo]

Now that’s some old-school hotness, right there.  I have to admit that I like #2; very trim, from this angle.

[Adam Kilpatrick]

Its interesting that Palante and LiteAF have started building robic packs. I think it sounds like a good fabric, should be plenty durable. I don’t think they are expecting them to be waterproof, certainly not like their DCF and DP options. I’m eyeing off the Multiday pack from LiteAF at the moment, its 210D robic all over.

Its interesting hearing where DCF and DP fabrics seem to wear. Apart from the obvious pack bottom (which is always easily, lightly reinforced when its made with a heavier fabric fit for purpose…and this is the spot that is least an issue for waterproofness unless you deliberately place your pack in puddles…) seems to be the lower back area, and, rolltops. The laminates don’t seem to like these spots in particular. I think if you want superlative waterproofness and are worried about the roll top, a lightweight detachable, simple lid is a straightforward fix. I’m sure this could be MYOG for about an ounce out of silnylon…detachable, easy to replace if it ever tears badly. The lower back area, well, lots of pack manufacturers now also prioritise slightly heavier fabrics in the back panel anyway (eg KS Ultralight).

Another thought is why not use a decent 3 layer WPB fabric for the roll top area? I doubt it would ever delaminate from the rolling and unrolling. Or just the latest heavy weight Silnylon (stronger) or Silpoly (better for UV on a pack)  fabric from ripstopbytheroll. The newer fabrics are pretty tough and reliably waterproof.

[Bonzo]

Apart from the obvious pack bottom (which is always easily, lightly reinforced when its made with a heavier fabric fit for purpose…and this is the spot that is least an issue for waterproofness unless you deliberately place your pack in puddles…) seems to be the lower back area, and, rolltops.

Agreed.  The pack floor – or any other area, really – is easy to fix with a small amount of high-wear fabric.  My 50L (built for heavier use) has ballistic nylon layers in those areas, but it’s the same principle, regardless of fabric choice.

Another thought is why not use a decent 3 layer WPB fabric for the roll top area? I doubt it would ever delaminate from the rolling and unrolling.

That’s exactly what is on mine.  Technically, it’s a four-layer fabric if you count the diamond-grid, but yeah…it’s not going to be coming apart anytime soon, it’s as waterproof as a pack can be, and it’s quiet.

On pack rotation from Sam’s earlier post: I’ve kind of noticed the same thing…but it’s really more about how the entire pack carries, for me.  When I get the center of mass of the pack in the right spot for my body type and my movement, it slightly rotates and flexes in the lower back area (right at the top of the hip belt, for me) which makes movement much easier; the more obvious effect, however, is that the pack seems like it instantly becomes 50% lighter.  With that kind of carry improvement, I stopped worrying about how much the pack itself weighs; it’s easier and more comfortable to shave weight elsewhere.  I’m sure that doesn’t hold true for everyone, but it was an eye-opening moment for me.

[Jerry Adams]

I like those those thoughts

I try to put my heaviest stuff on the side of my pack closest to my back.  Evenly distributed top to bottom so center of mass is in the middle

[Sam Farrington]

Jerry,

Looked for some time but did not find anything much better than what you are looking at, a woven ripstop 200+ denier nylon fabric at 4.4 oz/sq/yd.   You said in your OP, “Maybe 210 D Robic would be better?  It’s supposed to have a better waterproof coating. 4.4 oz/yd2.”  If that is the case, I think it is about as good as it gets.

There is some brief info about Robic on the Exped site:  http://www.exped.com/usa/en/backpack-materials

My packs use a heavier 6 oz fabric for the pack bottom, which is slanted upward so the rear edge will be higher and less exposed to water.  Before sewing in the pack bottom, I bond some 30D PU coated nylon to the inside of it to be sure it is waterproof.  Since both fabrics are PU coated, a thin coat of  SeamGrip works.  That seems to help a lot with the heavier fabrics that are not so waterproof.

I use waterproof fabrics for the body of the pack, seal inside the seams, and have never had to use a pack cover to keep things dry.  Found a nice sand color 3.7 oz double ripstop pack material at Rockywoods years ago, but for years all they’ve had it in is black.  Not for me.

[Author]

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