MYOG 50l pack with adjustable frame

[Milan H]

<span lang=”EN-GB”>Hi all,</span>

<span lang=”EN-GB”>I would like to post my new pack design, maybe others will find some information here. The suspension system was inspired by Exped Lightning, even though shoulder harness was modified a bit. Other inspiration was taken from David Chenault articles, thanks a lot for such a wealth of information. The pack is intended to carry 14-18 kg (30-40 lb) on longer, more isolated treks. The intention was to create water resistant, reasonably durable and also reasonably light pack capable of carrying intended loads comfortably. The 50l volume comprises main compartment only, all additional pockets are extra.</span>

<span lang=”EN-GB”>I actually considered buying Exped lightning, being quite close to my requirements, but due to multiple reservations to pack itself (absence of large front pocket, questionable lashing possibilities, not durable pocket material, etc.) decided to make my own.</span>

<span lang=”EN-GB”>The biggest issue was the hip belt. It took several iterations to make it functional, comfortable and not bulging. Finding right load carrying foam was main challenge, but I finally came across local industrial foam producer and was able to acquire samples, select right foam and buy large sheet for reasonable price. The belt shape was copied from older Osprey pack.</span>

<span lang=”EN-GB”>Features:</span>
<ul type=”disc”>

[Milan H]

Apologies for all the  <span lang=”EN-GB”>.. These were bullet points, new lines, etc.It was not visible like this when I prepared a post (copy pasted from different source). Once posted it seems I cannot edit the post any more.

[Jerry Adams]

nice job!

you have encountered both the html code bug and can’t edit first post of a thread bug : )

[Jerry Adams]

plus a new bug I haven’t seen before

your first post html code puts it into a weird mode where the rest of the posts look different

[Iago Vazquez]

Pack looks fantastic! Thank you for sharing :)

[Alex H]

Looks like you hit on a bunch of great details.  How is it carrying and what was the final weight?

[Geoff Caplan]

Your sewing skills look awesome!

How are you finding the 330d Cordura? Is that from Shelby Outdoor or did you find another source?

I’m thinking of using it myself for a pack project.

 

[Sam Farrington]

Is the adjustable frame a matter of a single ALU bar of lower temper that can be molded to the wearer’s back shape. Or is there more to it. Thanks.

[Lester Moore]

Nice job on the pack Milan, especially the adjustable frame.

How easy is the 3×20 mm aluminum stay to bend or conform to the desired shape? Are the stays 6061 aluminum? I’m considering using 3/32″ x 12″ (2.4mm x 12.7mm) or 1/8″ x 1/2″ (3.2mm x 12.7mm) stays for a prototype LW framed pack, with two stays per pack instead of one.

How easy it was to sew through the thick 0.4″ (10mm) eva foam plus fabric, and what sewing machine you used to do so.

And what material is the “AP 100” that you mentioned using for the hip belt stiffening?

[Milan H]

@AlexH: the carry is good. I tested a prototype pack with the same suspension last year in Tajikistan on 10 day trek through Pamir, no complaints. The only part which was not tested yet at full load is a hip belt. It performs good at about 12 kg. I hope it will perform satisfactorily at upper limit also. The final weight is 1080g (38oz). There are other small details not mentioned, for example small webbing loops enabling shockords to be replaceable, lash tabs at front to enable lashing snowshoes, contoured back panel according to Dave Chenault article, etc.

@Geoff Caplan: I like Cordura 330D a lot. At 185g/m2 this material is soft, yet seems durable. Nice for shoulder straps, pockets, etc. I would probably prefer it over other material for pack body also, if the pack waterproofness is not required and some durability is. In my view, such fabric will serve well with reasonable care, but will probably suffer if dragged or bushwhacked.  Also, it is less costly than X-Pack or Dyneema grid material. I plan on using it for other pack projects in the future. I sourced it from Extremtextil (DE) like all my materials.

@Sam Farrington: Probably a poor choice of words, I should have said:

• adjustable back length by shoulder harness position adjustment
• adjustable frame shape by aluminium bar bending.

Both features inspired by Exped Lightning, no ground-breaking innovation on my side. The frame itself is a single AlMgSi0,5 bar. Very cheap – about 1USD/main stay. It is hand-bent over empty gas canister to my back shape. 3x30mm performed well at upper mentioned trek in TJ with 18 kg (40 lb). I bought several dimensions of both stays for testing. I assume that 3x20mm might be OK as well – to be tested. Shoulder harness slides along the back stay and is held in position by a flat buckle located under lumbar pad. A couple of pictures added.

@Lester Moore: answer about aluminum stay above. Sewing trough 10 mm EVA is not such a problem, worse is feeding and actually getting the stuff under pressure foot. Not every machine will take 10-12 mm of material height. I used an ancient german Veritas which can just about handle it. Sometimes I had to manually help feeding. My newer machine would not take so much material under presser foot. My hipbelt design was intended to minimize sewing trough, not sure how others approach this if making more substantial belt. For shoulder straps, I used “rolled sock” technique rather than hemming around with  gross grain ribbon.

[Graham F]

Milan, top work.

I had a pack with a similar harness system to yours which was heavier overall than yours (1.7kgs) but was excellent at carrying 12ks+. You have solved the problem. Excellent system and good weight. You could sell these I reckon.

Might I ask how well the 330D integrated into ‘the sewing’ with the VX21. I would imagine that it would be kind to your machine, but what I am wondering is it do you think much kinder and worth it compared to say 500D?

I am considering making a VX21 pack with 500D cordura. But it would be on a domestic machine. I know KS uses a VX21 and 500D combo and combines 330D with the other (I believe less stiff/lighter) xpac 210c. I like the look of the 330D and if it would get through my machine that bit easier and ‘combines’ well in the manufacturing process with the VX21 I think I would like to try it. Can you share some thoughts on the 500D compared to the 330D other than the weight if it’s not too much trouble? Well done again.

Thanks.

[Milan H]

@GrahamF: it integrated well, not problem. As I said above, I have and ancient all powerful Veritas machine for packs. It handles several layers of tough materials. I was advised to use leather needles for it – thicker and different point shape, it worked. I have actually made other 40l pack from combination of 330D and 500D Cordura and some city pack from 1000D Cordura remnants. 330D Cordura I used is only AC coated (thinner coating, not that waterproof) so it is softer, easier to sew. PU coated 500D was stiffer due to both stiffer coating and more robust fabric.

Regarding sewing, I do not think there is a huge difference between 330D and 500D in multiple layers in combination with VX21. It will be a bit easier, but if your machine can handle multiple layers in general, possibly with webbing in between, then it should not matter which Cordura it is too much. May be try some tough fabric you have at home with webbing, or get some samples for test and you will see. If webbing would be a concern, it can be avoided in seam, but it is more work.

Regarding the combination, I would say that even though VX21 has good structural stability due to X pattern, the face fabric is only 210D nylon. I believe that abrasion vise Cordura 330D will handle more abuse. Using 500D with VX21 in one pack can be combining materials quite apart from durability perspective. Unless use of very robust material for high wear areas is an intention (pack bottom, etc). I would probably made my choose based on what durability I want to achieve.

[Graham F]

Děkuji mnohokrát Milan. I shall take your advice. I plan to use the VX21 on the body
for its waterproofness as it sounds you also did, and the C330 or C500 for
the pockets and straps. It is good to know that it works and sews well.
As I would be using a domestic machine sewing might be a concern.
I have 500D Cordura on another ‘bought’ rucksack but no-one seems to be using
the 330D, or at least not writing about it, so it’s great to learn something new.
Thanks again.
Cheers.

[Milan H]

Yes, that was my reasoning, waterproof body and reasonably durable and pliable straps, pockets, etc. If you want to use Cordura on pockets and straps only, I would go for 330D. In case you want to have a shock cord at pockets tops, you will have to use some other, thinner material for shock-cord tunnel. Neither of Corduras will “wrinkle” willingly. I was using some 80D nylon I had left over for that purpose.

In my view, much less durable materials (higher grade Lycra, mesh, etc.) are used in commercial packs for side pockets. Compared to Cordura 330D, these can be abraded or ripped much easier. I am more worried about puncturing or abrading VX21 pack bottom than any Cordura 330D part.

[Geoff Caplan]

Milan

If you’re looking for a more waterproof 330d Cordura PU, you’ll find it here:

https://www.shelbyoutdoor.com/product_info.php?cPath=402_22_161&products_id=3224

[Author]

Posts