Pack Fabric Selection

Dave C wrote a pretty good summary article to this material here:

http://bedrockandparadox.com/2014/01/26/pack-materials-rundown/

My first question would be, what is this pack intended for, just backpacking, or perhaps something a little more adventurous.

I made the mistake of making my first few packs out of the most bomber materials, and later learned the idea of more purpose built packs. Now I have a few different of various materials that I use for different applications, but I'm glad I figured out early enough that matching material to needs is the most aspect.

I like the X-Pac fabrics.

Cheers

I'll read through Dave C's blog article. I've already read his BPL articles.

Regarding use: it will only be used for backpacking. Probably 90% on trail with 10% off-trail.

What about a VX42 bottom with X21/VX21 body? Depending on the area where you're bushwhacking that should work fine. Seems like that's a fairly common combo on BPL over the years and it should have similar strength to Dyneema-X. If you need more abrasion resistance, step up to X33 or X51. Looking forward to pics!

Ryan

After reading the above, this is my current plan:

Extension collar: X21 RC (thought about TX07, but the weight savings would be 0.6 oz or less – seems worth it to go from 70D to 210D face fabric)

Side pockets/back pocket: X21 RC (I think it should be flexible enough to work okay – if not, I'll use 210D Dyneema)

Main body: VX21

Pack bottom: VX42

I estimate the main pack will require 1 square yard of fabric with the extension collar requiring less than 0.5 square yards.

Has anyone used VX21 for a pack bottom? By the time I use VX42 for the pack bottom, I will have only saved 1.5-2.0 oz over making the main body entirely from VX42.

Fwiw, I used VX21 for the bottom of 3 of my home made packs. So far no complaints! It was easy to work with and is durable enough for my needs. I do not baby my packs although I'm concious of the time it took to build them… My city pack sees daily use and my ice pack carries pointy gear and gets dropped often but mainly on snow and some rock. I will use this fabric again for my next packs.
Cheers

I will agree with others, in that case I'd recommend VX21. I had some ballistic nylon that I keep coming back to using on bottom of my packs underneath a layer of VW21. Overally the additional weight is 2-3oz extra, but that is well worth the weight of not working about tossing on ground.

You could also use D40 for a pack bottom. It's another Dimension-Polyant laminate, but it has a dyneema/polyester blend for the face fabric, and dyneema reinforcement. That stuff is incredibly burly and lighter than VX42. Cut it once with scissors and you'll understand.

It's pretty expensive stuff, although Cascade Craftworks sells it by the half yard. I think there was a pack maker who will sell MYOG folks a small piece to do pack bottoms, but I don't recall who it was. I would sell you a piece but I need what I have for some prototype packs at the moment.

John I think your plan sounds good. One layer of VX42 makes for a very sustainable pack bottom unless you're really beating on it. I'd not use VX-21 for a single layer bottom unless you're really trying to cut weight. The X21RC should be just fine for the extension collar and side pockets. The X series fabrics are a really nice, flexible, quiet option. TX07 is really loud and fairly fragile, not a fan.

Nick – I was actually looking through your pack thread the other night. At 6.9 oz/sq yd, D40 sounds like it would be a great in-between fabric (more durable than VX21, but not as heavy as VX42) for the main pack and bottom, but I cannot find any place that has it in stock.

I really like how my Exped Lightning 60 doesn't have a lot of seams, so in an effort to copy that, I am going to use VX21 for the main pack body and bottom. If I get the fabric in-hand and it feels "not durable enough", then I'll use VX42

Edit: Dave, why would you not recommend using a single layer of VX21 for the bottom? Have you seen it degrade quickly?

2nd Edit: just found out D40 will be back in stock soon, so I will go with D40 for the main pack + bottom. Cutting out the fabric sounds like it will be interesting

The face fabric of VX21 I've found to not be as durable as the denier would suggest. The common 210D gridstop is a tight weave and is significantly tougher, for example. The 300D face of X33 is also much better than VX21.

"Cutting out the fabric sounds like it will be interesting"

Try Kevlar shears.

Ryan

Simple, high-quality knife-edge shears work great for me. Make sure they've been sharpened recently ;)

Nathan, have you ever tried hot-cutting? I think that could work pretty well for D40 but I've never tried it.

No, I haven't bought a hot-cutter. Searing edges of webbing and cord with a lighter produces a smoke that irritates my eyes . Perhaps others have had different experience. I try to avoid noxious fumes, personally. I would imagine that it would work great, though.

I've used a soldering iron to cut nylon with good results. One project was untreated 1oz ripstop, the other something heavier, also untreated – maybe 70D. You do want good ventilation, and it's great that it keeps non-laminated material from fraying.

I use an old kitchen knive heated up on the stove to cut webbing and cord. Does a good job, nice and clean.

Well I am finished with my pack. My initial plan to use the frame, hipbelt, and shoulder straps from the Deuter Kid Comfort was a bust. Those 3 components were simply too heavy – I think around 28oz total.

So instead, I decided to copy the suspension design on my Exped Lightning 60 (which is currently the best pack I've ever used). I took the Deuter hipbelt and ripped out all the stitches. I then sewed in a thin piece of plastic into a layer of VX42 connected to the 3D mesh front:

From there, I sewed in horizontal and vertical straps to the hipbelt (to connect to the pack and stabilize the load). The top ladderloc is for the shoulder strap webbing to adjust the torso height. To hold the stay, I made a pocket out of 1.5'' webbing and VX42:

With the stay pocket made, I sewed all the components of the hipbelt back together. This required hand-turning my sewing machine, as the Deuter plastic on the hipbelt wings was very stiff:

With the hipbelt and shoulder straps done, I had the beginnings of a frame:

Here is how the center stay from the Exped Lightning 60 fits into the back pocket on the hipbelt:

I then sewed on all my compression straps and pockets etc onto the pack. For the main body, I used D40 (which actually cut very easily with an old titanium rotary cutting blade). For the extension collar and side pockets, I used X21RC (almost too stiff for the side pockets, IMO). D40 feels very tough, and I did not feel the need to reinforce any compression straps or daisy chains. For the top pocket of the stay, I used a layer of D40 folded over itself with some webbing inside. There is a small section of tent tube sewed in at the top to form the top horizontal bar (the load lifters connect just above this bar). The pack is roughly 39'' in circumference and 39'' tall – made big to handle my foam pad and lots of food or water. Somehow, one side pocket ended up an inch shorter than the other:

There's nothing on the inside of the pack, except for a little key pocket I made out of Argon Sil (weight = 4g):

I didn't have many seams to sew up the pack body. The D40 seemed prone to fraying, so I did a rolled hem after the main stitching line (also difficult for my machine to get through):

Here is the back of the completed pack:

And the front of the pack showing the hipbelt, stay, and shoulder straps (stay and shoulder straps are borrowed from my Exped Lightning 60):

This picture shows where the compression straps from the hipbelt connect to the pack. The horizontal ones are routed through/underneath the side pockets. The vertical ones go underneath the pack and connect to the bottom of the hipbelt:

At loads of 25lbs, the pack carries great. I would say it is equally comfortable, if not more so, than the Exped Lightning 60. At 33 lbs, the pack's comfort reaches a turning point and is perhaps only equal to the Lightning 60. Here is a picture of me wearing the pack with 33 lbs (yes, I have the torso length set too high here):

Unfortunately, with 37 lbs in the pack, the hipbelt begins to buckle and sag downwards. The Lightning 60 is definitely more comfortable at this weight. I think the plastic I used in the lumbar pad is simply too thin. Here it is with 37 lbs:

I experimented with the compression straps attached to the hipbelt. I first tried loosening them, thinking that maybe I had too much tension on them and they weren't letting the hipbelt get a good wrap. This made things much worse. I then tried tightening the bottom straps a lot. This helped things tremendously. It also shows how the hipbelt is deforming:

This then gave me the idea to try the pack without the stay anchored into the hipbelt. It actually worked very well. Here it is with the same 33 lbs:

No collapse or hipbelt buckling:

I think what is happening is that the CCF pad I have coiled inside creates a very rigid pack body. This rigid pack body then rests on the bottom compression straps, which transfer the load to my hipbelt. This makes me think the Paradox Unaweep's suspension concept is the way to go, since it acts in a somewhat similar manner (only with a frame to transfer the load to the bottom straps).

At this point, I am not certain what I will do with the pack. I could use the pack exclusively for sub-30lb loads, but I really don't want to be a multi-pack owner. I want one pack to handle all my backpacking needs.

I do not think I will continue pursuing the Exped Lightning 60's suspension design in MYOG packs. I will probably try to find some way to mirror the "hanging pack" design of the Paradox Unaweep, either by adding a new frame to my current pack and sewing or modifying a new hipbelt. Or by starting completely over with a new pack.

I think this pack does confirm that my problem with the Unaweep I used to own is that the straps on the hipbelt were sewn too far apart for my waist size (and that the frame is too big for smaller people).

Almost forgot. The finished pack weight with everything is 34.4 oz

mad sewing skills! nice work :)

I have an Exped 60 as well, wonderful pack- I wish it weighed a little less-mine weighs 40 oz on the button (like everything we pack), but there isn't much I'd change on it- carries like a dream.

Nice job! Thanks for the tip about the titanium rotary cutter blades – I didn't know they made those. I can confirm that D40 will dull a normal rotary cutter blade in just a couple of cuts. I just ordered a couple of the titanium ones for some D40 projects I have coming. :)