DIY Roll-top Framebag

[pilotintraining]

Background

So I’d only recently been struck by the backpacking bug, but a bout of spring-like weather here in southwest montana got me dreaming of riding buff singletrack into the sunset. This winter I picked up a sewing habit, so I figured, hey, why not make a framebag? After mulling it over for a while (talking with friends and reading lots of forum/blog posts), I set my heart on a zipperless roll-top bag, and that’s where this story starts.

Why not buy a perfectly good pre-made framebag from a reputable builder? I chose to build my own partly because I have much more free time on my hands than I do disposable income (read: unemployed) but even more so because there’s really only one option. I’m also stubborn and obsessive about small details.

The Orbiter (pic below courtesy of Fatcycling), while certainly nice, isn’t exactly what I was looking for. My main gripes are that that the roll system and strap harness look a little clunky and overbuilt, and that the 2-buckle closure leaves room for the roll to splay outward thus increasing the likelihood of hitting your knee as your pedal. The flaps where the webbing attaches seem like needlessly good places for dirt to accumulate, and the stiffening rod on the roll flap seems unnecessary. Please take this all with a grain of salt, because this is only my armchair-bikepacking conjecture, and many people love their PR bags. 12 weeks is also a long time to wait...

Revelate Designs has also, it appears, been prototyping some zipperless framebags, but Nicholas Carman and Joe Cruz are the only two internet-bike-celebrities (that I’ve seen) who have posted pictures (see below). RD’s closure system is enigmatic, possibly a wedge-shaped rolling closure? Possibly elastic? The one buckle/stiffening plate design looks interesting, but you can already see evidence of the fabric tearing around the buckle on Nicholas’ bag. I particularly liked the behind the seat-tube buckle to keep things tight. Unfortunately my queries went unanswered, so speculation (and internet pictures) were my only friends.

One holy grail example of roll-top design and function is Hyperlite Mountain Gear’s backpack. I’ve had mine (made with the heavier black hybrid cuben fabric) for 4 years, abused it in every way imaginable, and it’s still going strong. Their roll-top design served as my main inspiration, and I also modeled many small details (webbing attachment points, buckles) after theirs. I would have loved to make a cuben bag, but it seemed too difficult to work with and expensive for my first frame bag, maybe next time.

I began with lots of sketches, a cardboard template, and a prototype bag made of old pants (see fourth pic below). This was a hugely important step for me in terms of figuring out the layout, sizing, and construction. I chose to use a 8” roll top closure with three buckles plus the behind the seat-tube buckle. At this stage I also decided on three 2” velcro closures for the seat tube and down tube, and 4 on the top tube.

There’s a vast body of internet knowledge about fabrics, sewing details, and diy bikepacking bags, all of which are readily googleable, so I won’t waste your time linking to every single post I referenced. I will say that I was surprised not to find any other DIY or MYOG folks who’ve done a roll top frame bag yet… maybe I didn’t look hard enough.

[pilotintraining]

Materials and Construction:

Necchi BU Sewing Machine and various hand-me-down sewing trinkets (thread clipper a must! scissors worked just fine for cutting when used carefully with a good straight edge and a flat work surface. A lighter was handy for burning off loose thread/webbing ends.)
Schmetz Microtex 90/14 needles
Coats and Clarks heavy duty 100% polyester outdoor thread

from www.rockywoods.com :
- Dimension Polyvalent X-Pac VX21
- Cordura 1000D nylon
- ¾” nylon webbing
- buckles
- 2” velcro

The construction was fairly straightforward, my only advice would be to take one’s time. The only errors I made were when I was rushing or not paying close attention. None of these ended up impacting the functionality of the final product, but they are noticeable if you look closely. The interior cordura panel on the seat tube is inside out, and I sewed over the hook velcro tabs into the opposite seam on the seat tube.

[pilotintraining]

Finished bag:

Overall I am very pleased with the results. Other than a few wonky stitches (the corners were quite tricky) and the items noted above, I think it turned out pretty good for my first attempt. The behind-the-seat-tube buckle could use a bit of refinement, and I might make the roll slightly longer next time, but it seems trail ready. I opted not to use any sort of liner fabric, seam tape, or seam sealant, time will tell if that was a wise decision or not. I'd be happy to answer any questions about the build/design, and sorry for the abundance of crappy iphone pictures.

Now to wait for the rest of the snow to melt. Thanks for reading!

[Adam Alphabet]

Nice Work! and nice lookin' Sklar.

[pilotintraining]

Nice Work! and nice lookin' Sklar.

Thanks! That's Sklar frame #4, much like the bag it has it's fair share of quirks. Great to see how much his frames have improved!

[Adam Alphabet]

Thanks! That's Sklar frame #4, much like the bag it has it's fair share of quirks. Great to see how much his frames have improved!

Awesome! just like anything handcrafted...we get better with practice. Can't wait to see all the NAHBS stuff coming soon.
Cheers.

[drwelby]

I will say that I was surprised not to find any other DIY or MYOG folks who’ve done a roll top frame bag yet… maybe I didn’t look hard enough.

I've done some tyvek roll-tops:

This one rolls over the top tube. There's another small bagmaker who does this where i got the idea.



This one opens on the side like most other bags.

[pilotintraining]

I've done some tyvek roll-tops:

This one rolls over the top tube. There's another small bagmaker who does this where i got the idea.

Thanks for proving me otherwise! I knew there'd be some folks out there who'd tried it.

How is the tyvek working? I've used it as a ground cloth/tarp for a few years, and other than the noise its an amazingly burly material. How did you attach/ reinforce the shock cord mounting points? Also a sweet looking frame, the fillets are nice!

[drwelby]

The tyvek is working fine. It's meant to be more of prototype material to try out some designs as well as test some ultralight concepts. I salvage it from construction site dumpsters so it's free, and I bond it together with different tapes so it's very fast to build bags and modify them. Without  sewn seams it's more or less waterproof - i.e rainproof but not submersible. Good enough for messing around. Main main concern would be tearing, though it's easily repaired with tape. I don't think I trust a long, burly trip to it, but I don't have enough time on the bags yet to tell.

I've heard of people laminating it, and you could cover it with heavy duty duct tape or hexamid tape, or armor it with thin plastic sheet or something like avalanche fencing. Or you could use it just as an inner dry bag and have plastic side panels that lace, like Rick Hunter has been doing.

Since I'm not sewing these that means no zippers hence the roll tops.

The cordage mounting points are reinforced with strapping tape. You can see them in the first picture, they're actually just strapping tape looped over the edge of sheet and captured on the inside seam. On the second photo they tape is on the inside and the side sheet has extended tabs that loop to the inside seam. This locks the strapping tape in the seam, and protects it from UV.

[DanimusPrime]

Great work!  Do You have any patterns drawn from these that you are willing to share?  Interested in making my own!

[n8]

I am in the process of designing a frame bag too. I have been thinking about a roll-top. However, Im not sure why? I can't really think why it is better than a zipper. What are the benefits? Why did you guys choose a roll-top construction over a zippered?

[pilotintraining]

Great work!  Do You have any patterns drawn from these that you are willing to share?  Interested in making my own!

I've attached a couple of sketches showing the setup (see below). Note: Strap configuration is fully customizable, this setup works well for me. Rib width is also customizable, I opted for about 3" on all edges, but if you want to get fancier, you could make it wider near the front and narrower towards the back/bottom. All fabrics used in this project have a front and a back face, so take care when laying out your cuts/seams to ensure that the 'right' side will be facing where you want it.

The length of the Roll (height of the roll panel) is up to you, I keep it around 8-9". This seems to work well for 3 rolls on an empty bag. I line the anchor webbing up parallel with the TT, and ~5-6" below it. Closure webbing length is tricky to get exactly right before bag construction. I got lucky on my first version of the bag, but to save some headache on later versions I opted to include a couple extra inches of webbing, and then finalize the length after the bag was complete. I keep a lighter close by when I'm sewing for burning raw webbing edges and loose thread ends.

When making your template, round the edges! Rather than making 90* corners, I've found that it works better to make a 30* turn, sew 5 stitches, make another 30* turn, etc. This results in a curve with about a 1" radius, but works better for heavy fabrics than a 90* turn. It also helps to make a couple of short cuts to the fabric perpendicular to, and on the outside of your prospective corner seam. I now use a 0.25" allowance for all seams, but you might go bigger than that on your first bag (to accommodate user error). I would suggest measuring very carefully and using your template on a flat surface, mark the top face of the side panels (you can get marking chalk from Jo-Anns, but a sharp #2 or white colored pencil works just as well) for webbing and velcro location. Depending on how good you are at spatial visualization, you might find it helpful to clearly mark the front/back/top/bottom of pieces. Measure twice, cut once!

Build process is as follows:

1. Cordura patches to bottom of x-pac panels. I sewed these front-to-front, then top-stitched the seam again.

2. Closure webbing to anchor straps, making sure to get spacing and angle appropriate. You could bar-tack or box x stitch, but I just do a couple passes of zig-zag stitch and I've had zero separation.

3. Anchor webbing to side panels, stitching on both the top and bottom edge of anchor webbing. Ensure that closure webbing is underneath the anchor webbing. Also I use rubber bands to keep the webbing rolled up and out of harms way from here on out.

4. Hem top edge of drive side panel and roll panel.

5. Attach all velcro tabs to side panels. This is somewhat tricky to explain, I wish I had pictures - but, line the short edge of the strap up with the edge of the fabric so that the strap points in towards the center of the panel. Construction of bags always happens inside out, so your straps should face the right direction once the bag is flipped right-side-out. On the non drive side, I do the loop facing down (panel fabric facing up, or back-to-front), and on the outer drive side, the hook facing up (front-to-front, only on the DT and ST straps). For the roll panel (TT straps) the hook faces up (back-to-front).
 
6. Assemble the ribs. A great time to practice straight sewing. In later versions of this bag that I've made, I've used thin  (1/16" or 3/32") closed cell foam and a lightweight nylon ripstop fabric as a liner. I've found it works best to sandwich all layers right away rather than try to stuff the padding in later. Also, the length of the rib segments is somewhat arbitrary, as long as you end up with the total perimeter of your bag. I've done a rib segment for each side of the bag (not advised, as the seams in the bag corners are a huge pain) and 1 rib segment for the entire perimeter (simple, but unwieldy) I would say shoot for two segments and have the seams between them on straight edges of the bag.

7. Rib to roll panel

8. Drive side panel to roll panel, including the rib at the bottom of the roll panel (panels are front-to-front here).

9. Finish attaching rib to drive side panel

10. Non drive side panel to the other side of the bag.

11. Flip bag right-side-out. Ensure that straps line up, orientation is correct, etc.

12. Attach velcro to roll closure. You can do this early on, but it's easier to make sure they line up if you do it at the end.

13. Reenforce stitches where necessary. I usually double sew all seams and add a little extra on any corners that seem iffy. If you are super pro, you could also use seam binding ribbon here.

14. Finalize webbing lengths and attach buckles. For feeding the strap between the TT and bag, the female buckle should fall ~1.5" past the top of the bag. Play with the length of the male straps so you have room to get the buckles nice and loose (to accommodate an over-stuffed bag, or if you want to strap tent poles or a fishing rod to the outside), but keep excess to a minimum. Pro details here include making sure that raw edges of webbing fold to the inside, and folding the loose end of the webbing back on itself to prevent it from slipping through the buckle.

15. Round off the sharp edges of the velcro straps with scissors.

Voila! You've got yourself a framebag. I've made several iterations, and things have stayed largely the same. I found the rear buckle wrapping around the ST to be totally useless, so that got the axe, but overall I think the design works quite well. The major improvement that I am scheming on for next summer's bags is a way to manage the extra webbing that dangles out of the male buckle ends. Perhaps a loop of elastic, a velcro tab, or a button even? Hopefully that helps!

[pilotintraining]

I am in the process of designing a frame bag too. I have been thinking about a roll-top. However, Im not sure why? I can't really think why it is better than a zipper. What are the benefits? Why did you guys choose a roll-top construction over a zippered?

Good question n8. Zippers are an excellent closure choice for lots of sewing applications: they are low profile, flexible, they can be *mostly* waterproof, and they are fast, but, there are several aspects of framebags that makes zippers a poor choice (in my opinion). Lots of these reasons are outlined in blog posts and gear reviews elsewhere, but in brief:

Zippers do not have high crosswise chain strength and they are prone to damage when opened or closed under force – situations that are all too common when trying to pack a few extra calories/laters/etc. into your bag. Furthermore, the fabrics often used in framebags are extremely strong, but non-compliant (not stretchy) which translates all the force of a heavy load onto the weak point (the zipper). Zippers also do not handle dirt well. Bike packing gear should be able to withstand a thorough dousing of mud, but even the heaviest duty zippers will wear out over time, and the dirt and grime of offroad miles exacerbates this. Lastly, if you are out on the trail and experience a failure, zippers are extremely difficult to field repair. Roll top closure systems are much more resilient to wear and tear, and they are much more readily repairable in the field.

I have made a couple of frame bags with zippers (pic below) and while they work well enough(even stuffed with a 6 pack of tall boys), I do not have the same confidence in them to last the lifetime of a bike the same way I do with zipperless bags. Good luck with your project and let us know how it goes!

[mmeiser]

I've done some tyvek roll-tops:

This one rolls over the top tube. There's another small bagmaker who does this where i got the idea.



This one opens on the side like most other bags.

Any chance you can repost / upload your photos to this thread again!?  I recently purchased a tyvek for a winter hot tent and have an extra 9x100 feet or so. I love that I can tape it with white gorilla tape since I have no sewing skills. Even though I already have revelate frame bags, none of them have roll tops. The idea of making a custom one in white for my fatbike has me jazzed. Also thinking about making waterproof stuff sacks, rain skirt, snow mitts... The sky is the limit. I heard once their was a guy whom hiked the AT with nothing but tyvek. The grandma gatewood of tyvek, lol. So much fun as a protype material.... and yet may be something more then just fun.

[VermontGal]

For those wanting pics of the tyvek framebag, they are still available as of Feb. 2019 if you look at google image results for the search "DIY tyvek bikepacking.net frame bag."  Not the top hit, but maybe 7-8 images down.

[steel_wheel]

good day dear pilotintraining
good day dear all,


YOUR BAG LOOKS really AMAAAAZING! Thanks for sharing!


well - i hav to say: Ever since I saw this I?ve been planning to make my own?

 thank you very much buddy, for the inspiration! I?m ordering my fabrics right now actually! The only segment I?m having a hard time thinking of how to do is the triangular shaped piece at the bottom of the ?bra? strap..
 
 
 BTW: saw a simmilar bag here: https://flamingbike.com/2015/06/23/roll-top-framebag/
 
 But - yes:  Awesome - your framebag drives me nuts  - i love it  do you have some plans how to create it - love to hear from you