design questions for a new pack
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Jeff Cadorin
(JeffCadorin) - F

Locale: paper beats rock
design questions for a new pack on 10/06/2011 20:30:49 MDT Print View

Hello all. I am going to make my first pack. I have a few questions about some aspects of my pack idea.

1. Has anyone used linelocs and rope in place of buckles and webbing for shoulder strap tensions? Whats the weight compacity, pack load wise for this kind of setup? Any durability issues for the linelocks?

2. I am using silnylon, heavy duty mesh and dyneema x. What is the correct method for sewing all three together? Im sure one way or another is better for the longevity of the 1.1sil.

Im sure ill have more questions. Thanks in advance for any advice

Daniel Sandström
(sandstrom.dj)
Re: design questions for a new pack on 10/07/2011 04:08:42 MDT Print View

I've made a
pack with linelock - cord compression system. I don't recommend makin a continuous zig-zag compression like mine or the ULA Ohm. Done this way the tension will change as the load bounces, in the end you'll have more cord in the lower part of the compression system. The right way to make a zig-zag compression is to have two (or more) V's. Remember that you'll probably also need a D-ring to fasten the cord at the oter end/middle point.

Ultimately. Are cords, linelocks and D-rings really lighter than webbing and ladderlocks, say 10 or 15mm ones. The webbing is easier to sew and also lies flat onto the pack.

Some thoughts. Personally I really like the linelock - cord system, think it's a Beutiful solution. But. I'll probably choose webbing - ladderlock next time, because it scores higher in Function.

Happy sewing.

ps. don't have any exp. with sewing the materials you mentioned, sorry. ds

Samuel C. Farrington
(scfhome) - M

Locale: Chocorua NH, USA
design questions for a new pack on 10/07/2011 23:44:46 MDT Print View

1. Has anyone used linelocs and rope in place of buckles and webbing for shoulder strap tensions? Whats the weight compacity, pack load wise for this kind of setup? Any durability issues for the linelocks?

Using cord instead of webbing increases the chances of its getting tangled on any number of things it comes in contact with. The webbing also will be much less abrasive if it rubs against you or your clothing, and is better at keeping the straps from twisting. When you are putting on and taking off the pack, resting your hand below the pack straps, wrestling with the pack when fording a steam, falling, sliding in the snow, or any other situation where you end up grabbing the pack by the cords, they could become quite painful and/or annoying compared to webbing.

But if you are shaving grams, a lineloc setup would be much lighter as you imply, and spectra cord is plenty strong. Don't know if it is as durable as quality nylon webbing that lasts many decades. As for the linelocs, however, just looking at and comparing the sizes of the components of a 3/4" acetal plastic ladderlock buckle vs. an acetal lineloc, the buckle has to be quite a bit stronger, and spreads the force of the web under tension over a wider area. But if you are making an ultralight pack for carrying only in the under 20 lb. range, maybe that would not be important.

I carry in the 20-25 lb. range when loaded with a full week's food and my camp chair; so want something dependable like buckles, and prefer the webbing for the reasons mentioned above.


2. I am using silnylon, heavy duty mesh and dyneema x. What is the correct method for sewing all three together? Im sure one way or another is better for the longevity of the 1.1sil.

The 1.1 oz nylon with a sil coating will weigh 1.3-1.5 oz per sq yd.
While the coating adds some resistance from unravelling to the fabric edges, the silicone does less well at this than PU. Consider using GE silicone glue (not sealant) to fold over and bond the edges of the fabric before sewing. This will greatly decrease the chances of unravelling, and also allow you to use greater thread tension, tightening the seam without puckering the fabric. I use a small hand roller, and first crease the folded edges with an iron, a risky process because it can greatly weaken the fabric, especially if the iron touches more than just the crease, or is too hot. But for me it beats having to clamp and dry the entire length of each edge.

Not sure about "dynema x," but many of the meshes, like the one called "leno" by some of the vendors, easily unravel. (There is a heavier, coated leno also, but if you are shaving grams, doubt you are using that.) The mesh probably can't be bonded at the edges like sil, but you can still fold the edges over and hem it with a row of light stitching. The dyneema will probably bond with Elmer's or Lepage's urethane glue, but haven't tried it. Buy urethane glue only in small quantities, because it cures rapidly in the container.

True lap felled seams are nice, but very difficult for a nonprofessional. There is the faux lap fell seam, which is just two pieces sewn together near their edges, with one wider edge folded over the other, laid against the material, and resewn with a second seam. This also traps the raw edges inside the seam, but is not as water resistant as the true lap fell seam, because the needle holes in one of the seams are not backed up by additional layers of fabric.

Consider one-fold hems on all the fabric edges, bonding the hem where possible and stitching where not, then pinning the edges together so that the raw edges face each other with maybe a 3/8" overlap. Then stitch with two rows of stitching as you would a lap fell seam. The raw edges will be concealed, and the bonding will reduce possible unravelling. Pin only between where the two rows of stitching will be, and seal the pinholes and seam after completion.

Sometimes the above seam is not possible, in which case consider the classic seam we see on all the cheaper tents: Sew the edges together, and cover the joined edges with binding that is wrapped and sewn over the stitched edges. Look in the shops for binding that has a woven, rather than a raw, cut edge as found on the binding on the cheap tents that is made of strips cut out of the tent fabric. Even this type of seam will hold up fairly well if the edges of the fabric have been hemmed and bonded first, before they are joined, but it does not look as good as a the first seam described above.

Hope this is helpful.

Edited by scfhome on 10/08/2011 00:11:55 MDT.

Terry Trimble
(socal-nomad) - F

Locale: North San Diego county
design questions for a new pack on 10/08/2011 00:09:13 MDT Print View

I made a small day pack about 18 to 25 liter I used line Sterling 1.75mm cordage for the straps line loc 3 ladderlocs for the shoulder straps, hip belt wings I used 1.75mm cordage a WSR line loc3 buckle,The sternum strap I used 1.75mm cordage the WSR line loc 3 buckle.
LineLoc3 and cord management cord guides and sterling 1.75mm cordage for compression on the pack.

It was study to see if I could make a really ultralite pack with hardware that weighed only a few grams. I loaded about 10 lbs. in to the pack went for a couple mile walk around my town and what I experienced was the pack swayed back and fourth at the shoulder straps. So I scraped the design I deemed the experiment a failure and went with 5/8" webbing and straps and Itw nexus jet series of buckle and ladderlocs.

I know ULA used Line loc 3 ladderlocs on one of their commercial pack for shoulder straps the sold for awhile then discontinued use for webbing and ladderlocs .
Terry

Jeff Cadorin
(JeffCadorin) - F

Locale: paper beats rock
design questions for a new pack on 10/08/2011 19:01:38 MDT Print View

Thanks for all the great info all. I am not necessarily making a super lite pack. I am watching weight of course but not obbsessed with every gram. Durability is more of a concern. I was kicking around the lineloc idea but figured it would be more widely used already if it was reliable. I also did not realize unraveling was such an issue. I have made a synthetic quilt using 1.1 uncoated nylon and a bivy using 1.1 and have not noticed any signs of the material unraveling. I will have to keep an eye out for that.

I am still undecided on the pack closer. I have grown to love the roll down and snap style packs( like an mld newt) but like the extra volume of the draw string style packs. I have been throwing around the idea of using the snap top with a hidden extension coller out of 1.1 to use when needed for extra food or layer of clothing for Colder weather.

Over the last several years i have paired down my gear to suit my style and expectations of my trip. I consider my kit very minimal and no matter what time of year i go only slight volume changes occure. I know my needs will change in the future but for now i am trying to make a rugged do all go anywhere pack and the coller would help me extend its use. I will probably drop the roll closer option even though it would really help stabalize and shrink the pack with a lighter load. I am still at the drawing board with this.

Luke Schmidt
(Cameron) - MLife

Locale: The WOODS
Hipbelt on 10/08/2011 22:17:43 MDT Print View

Are you putting a hipbelt on? If so measure your torso carefully and if in doubt add a bit because it will compress a bit under a load.
I made one pack with a thin webbing hipbelt. The belt was comfortable but there was only ONE spot on my hips where it fit okay. On my last pack I made the hipbelt about 3 inches wide. What this means is that I can adjust it up and down a bit on my hips to get a better fit.
As far as sewing goes remember the 1.1 sil is going to be your weak point so sew it to the heavier stuff in a way that distributes the stress around.

Terry Trimble
(socal-nomad) - F

Locale: North San Diego county
design questions for a new pack on 10/09/2011 10:36:51 MDT Print View

Jeff said:
"I know my needs will change in the future but for now I am trying to make a rugged do all go anywhere pack and the coller would help me extend its use."

What I gather from your post is you want a tuff pack that will last throw out idea of 1.1 fabric except if going to be used for small sewn in internal pocket.

Build it a little heavier use thru hiker Dyneema X Gridstop for the whole pac and the pop out extension. Or all Xpac from rocky woods using Vx 21 in a darker color for the pack body and the ugly lime green VX07 they have fot the pop up extension.
If you are set on using a lighter fabric for pop out extension use 1.9 coated rip stop nylon instead of 1.1 ripstop.

It better to over build and carry a ounce or two extra than have a gear fabric failure on the trail.
Terry

Jeff Cadorin
(JeffCadorin) - F

Locale: paper beats rock
pack design? ?? on 10/09/2011 13:10:02 MDT Print View

Terry. I am using the 1.1 as the panel behind the front mesh pocket. It will be fully protected and save some weight. I am going to use it as the back panel as well just behind the pad sleeves to hold my neo in place. Whatever coller i make will have some 1.1 used if it makes sense. I will not use it like you mentioned to save just an ounce or two.

I am making the pack with no hip belt. Weight carried in the pack wont call for it. I am however thinking of sewing a loop or d-ring in where the shoulder strap webbing meets the pack at the bottom. This way if i am ever doing anything with technical difficulty or want to run i can atleast use a guy out rope to keep the pack from bouncing.

I do have another question in general. Does anyone have any experience with making lightweight shoulder straps. I am thinking of making mine with just spacer mesh and the xgrid on top. I will never plan to carry more then 15-20 lbs max fully loaded. I was even thinking of just using two layers of the spacer mesh back to back and then bind it with the xgrid fabric. I thought i had seen something like that done on here before but cant find it. This i would expect to breath very well and cut down on the sweating under the straps?