new zpacks pack: the arc blast

See the post above for the specific changes I had them make. Don't really know what I think of the side top closure attaching directly to the pack (kind of assumed there would be extra strap to adjust it…maybe it won't matter – don't know).

and here is a close-up of the side buckle that I had they do (instead of the top dry-bag closure).

Here is a close-up of the Zimmerbuilt shoulder pockets that I added to the pack.

Bag looking from the side, showing proper shoulder strap alignment (they moved the attachment point down 1.5 inches and it fits me very well).

and here is a front view, with me not really ready for the photo to be taken…oh well.

Just back from my first proper trip with the Arc Blast. Loved it.
For those interested I walked the Mt Solitary, Kedumba River loop in the Blue Mt's, Australia. This track had plenty of sandstone rock scrabbles and a lot of abrasive scrub on the track sides. 34km's, 2800m elevation gain and I was on the track around 10.5hrs (Notes have it as a 3 day loop)
At first I was sceptical of the durability of the pack with the bumps and scraps of the track. I shouldn't have worried. The packs just as clean looking as when I left. Same cannot be said for my sunglasses which have a nice deep 1.5" scar right across left eye lens. The glasses were hanging from the from left shoulder pouch. If the scrub could do that and not even phase the pack that's good enough for me. There was plenty of wizzing noises as the pack (and me) pushed through the spiky dry scrub slightly overgrowing the trail.
The frame works great transfering weight to the hips and the ventalation is very similar to my Exos 46.
I had a baseweight of 4.1kgs (9 lbs) and carried 600g of food + 3 litres of water for the dry camp on the Mt. In no way did I push the weight limit of the pack but it felt great to wear and my back definately wasn't as sweaty as a regular non vented pack. I has heaps and heaps of space left for more food and gear. The side clinch straps were half way in and the rolltop was right down to the top of the frame. Plenty of room for more food/gear for sure.
All in all I'm completely sold that zpacks is onto a winner with this design.

Does anyone know if the volumes quoted are for the main pouch only or does it include all the pouches as well? If its for everything anyone know what the volume is for the main pouch only? The max load is rated as 30 pounds, is that really pushing this pack or can it really take that weight? Thanks for any info . . .

I used my Arc on a recent week long trip in Desolation Wilderness, part of three days off trail. I had only 22-25 lbs. if that much. I adjusted the stays and they did a good job of stopping gear poking my back, but I still had a sweaty back. I had to readjust the waist belt alot, but my shoulders were still ok. That's all I can offer.
Duane

I recently completed the Sierra High Route using the Arc Blast. Here are my impressions of the pack.

This was the updated pack with 2 horizontal stays & taped seams. I added 2 hip pockets and the total weight came in just under 18oz. My starting pack weight was about 24lbs without water – I generally carry very little water in the Sierra since there is good water readily available everywhere. This was with 6 days of food to make it to the resupply at Reds Meadow. I tend to be pretty weak in the core and upper body, so wanted to distribute as much weight as possible to the hips/legs. The pack did this extremely well, and I had no problems with the weight, even on the 6000' climb the first day with the heavy pack. As pack weight dropped it became so comfortable that I barely noticed it. This was extremely important for efficient travel on the SHR where there is TONS of rock hopping. You want a light pack that carries exceptionally well and doesn't throw off your balance, and the Arc Blast was just that.

The "arc" feature never worked for me. Tensioning the arc with those tiny cords is hard, and once I got it tensioned as per spec the cord locks would invariably pop loose after a short time. Also, I noticed that when it was in "arc" mode there were uncomfortable pressure points where the stays pressed into my hips. Fortunately, I found that the arc was entirely unnecessary and the pack was completely comfortable without it. I added a thin, 0.5oz piece of foam between my bear can and my back to ensure a comfortable carry, but I'm not sure if this was really needed.

Hip and shoulder belts are very comfortable. I'd prefer if Joe used a wider (2") webbing to connect the shoulder strap to the pack, as the thinner (1.5") webbing would invariable twist when pulling on the second should strap. Not a big deal, but I think easily fixed without adding hardly any weight. With my old pack I would always get some chafing on top of my shoulders in the first couple days of a long hike, but that didn't happen with this pack, thankfully.

The hip pockets are huge, which I like. I carried all food for the day in one pocket, and my camera & other ditties in the other pocket. The closures are a bit awkward and hard to close with one hand, which constantly annoyed me, but isn't really a big deal.

I love that the pack is completely waterproof (with taped seams). Means that I don't have to mess with a pack cover or liner. It didn't rain on the SHR, but I did use the pack in rain in Colo prior to this trip.

The material seems quite durable. The SHR is brutal on gear (and skin), but I had no problems there.

That's pretty much it. I love this pack & hope to get many trips with it. It is so much more comfortable (and lighter) than my old, frameless Jam2. If anyone has questions I'd be happy to try to answer from my experience. I hope to put up an SHR TR later this month.

The arc cord locks popping lose happened to me as well and is actually a defect according to Joe that has since been fixed. They've reconfigured the way the back piece ties into the cord locks with a nifty little couple of loops so that they there is less pressure and they don't pop. I've had the Exos (predecessor to Arc that did not have arc) and I've used the Arc Blast and the Arc is superior in my opinion …. glad it worked for you, but I would not go back to using the pack without the "arc" after using it with the "arc" …. :)

Interesting about those cord locks. That's been fixed since when? I got my Arc Blast in the beginning of June. I don't see any need for 2" of arc, but a slight arc might well be a bit more comfortable.

Fixed in last month or so …. Yeah, I think that even if you just give it a teeny bit of arc, that little bit of space might work out nicely, give it a shot! :)

Just to add my $.02, I have a new (received in September) Arc Blast and I have had no issue with the linelocks slipping and the arc not staying arced.

Got a cuben Arc Zip now too, it's really nice – however, what I don't get is why those cuben packs always feature shoulder straps in cuben, making them very stiff.

Personally I'd like to see this in a softer combination of foam and netting like the Nigor Moyo or Osprey backpacks have..

chbla: Got a cuben Arc Zip now too, it’s really nice – however, what I don’t get is why those cuben packs always feature shoulder straps in cuben, making them very stiff. Personally I’d like to see this in a softer combination of foam and netting like the Nigor Moyo or Osprey backpacks have..

At the time that I was developing the Arc Zip ZPacks only offered backpacks made with cuben fiber, so I had no other option then to go with cuben fiber shoulder straps.

I do agree that they are stiff and not all that comfy, but just have to remember that the Arc Blast generation is only designed for lighter loads. Much over 20 pounds and most folks find the backpack to be maxed out.

The new arc haul zip dyneema has significantly more comfortable shoulder straps and an amazingly comfortable hip belt.

Later this year I am going to be submitting some recommendations to Joe for the next generation of the ZIP and one of the things I am going to push for is the 3d mesh padding on the non-haul ZIP. Will also be trying to make some changes to the zipper, compression straps and such. Some of it is feedback I have gotten and some of it is just necessary changes for the next generation.

One of the nice things about the current generation of the non-haul arc blast is that the shoulder straps are very very easy to switch out with other shoulder straps – because of how they are attached to the backpack. If you can find yourself a pair of shoulder straps from the previous generation of SMD backpacks, score them and swap them out with the zpacks cf straps.

Anyway, hope that gives some insight/response to your issue Chris. And, nice to know somebody out there is buying the ZIP!

Thanks for the detailed answer John!

Although I'm hiking lightweight, I'm carrying a rather heavy DSLR plus Tripod (it's worth it in my opinion :). So I was looking for a UL backpack with frame. I've got the camera in a bag attached to the hip belt and the tripod at the side of the bag.

One more reason to chose the ZIP is that I am used to Fstopgear photography backpacks. They have a large opening at the inner side of the backpack (at the back). And being able to open a backpack full length instead of top only is for me one of the most comfortable things existing.
Unfortunately there are not too many companies making these kinds of bags :)

A further great point is the net and adjustable distance on the back, much better in hot conditions. I'd like to have a smaller pack with this system for mountainbiking (20-30L) to not sweat so much on the back.

Anyways, I agree that the dyneema version would probably better on the straps, it's way softer than cuben.. but you can't have it all I guess :)

Which SMD shoulder straps did you mean to use on the Arc Zip? Do you have a link?
I was referring to osprey straps like these: http://sectionhiker.com/wp-content/uploads/thumbskeep/P1020967.JPG and the Moyo seems to have something similar: http://images.ultralightoutdoorgear.co.uk/images/products/1400855068-48628000.jpg

It would really be nice if Zpacks would offer alternative straps as an option like the other features.

I think of the zip as a big failure point. It probably wouldn't give you problems soon, but over time if something were to go wrong it would be that zipper first.

It wouldn't be life or death, you could tie it shut with some cord to finish the hike etc. But a roll top is expandable and won't fail ever.

Hey Michael,

I noticed that ZPacks have recently added some supplemental padding for the straps. See this link:
http://www.zpacks.com/accessories/strap_pads.shtml
It looks like for the pair of pads they add just under one ounce to the pack.