Lining

[cpau]

I've had a lot of trouble with urethane inner coating/lining flaking off when bags get old (as in 7-10+ years). I have a LowePro camerabag, a Tatonka daypack and a large travelpack all with the same problem. The travelpack is by far the worst (and the oldest, at 17 years now). I have kept all my bags in top condition otherwise and really don't want to part with items that are in all other respects really well designed and in excellent nick. I'm particularly sad about the travelpack because larger backpacks are just not made in such a perfect shape for me (short, wide) these days, and it was supremely comfortable to carry.

I've never washed or abused my bags in any way. Perhaps I'm unrealistic to expect that bags should last so long, but I don't think so.

I've recently become a fan of travelling light, so I'm considering getting an Aeronaut, but due to the problems I just mentioned, am wondering about longevity. I'm not talking 3-5 years, but much longer. If/when the lining starts flaking, what can be done?

[pretzelb]

I haven't owned a TB bag for 7-10 years so I can't say if it will hold up that long or not. I would expect it to but I'm not sure if it would meet your requirements (I would expect some wear after that long). I do own an Aeronaut and find it very high quality so far.

Someone like Darcy will probably chime in to make an official statement but below is a quote from the website on the guarantee. You may interpret this differently than I do but I'd say that "do not expect them to last forever" may be the key phrase.

Defects in materials or workmanship are uncommon and almost always evident while the product is still new. If something goes wrong and it's our fault, we'll fix it for free. Repairs due to normal wear and tear or otherwise not our fault will be done at a reasonable charge. Keep in mind that daypacks, messenger bags, and briefcases are often subject to extreme wear in everyday use: do not expect them to last forever. Only true-love lasts forever! You can expect a TOM BIHN product to give years of hard service.

[cpau]

Just to be clear: the problem bags are not Tom's. I have confidence that he uses the best materials he can find. Perhaps I am unlucky with a dodgy batch of material, and things have advanced over time. Tom has been making bags for 20+years, so I was interested to hear what his experience was with coated materials. I have found nothing at all about it on the net.

10 years is not "forever" and this is not extreme use nor would I even consider it normal wear and tear - it is a breakdown of materials after not very vigorous use. If it was a bit whitened overall and rubbed off in high stress areas I'd not be too concerned, but this is a wholesale flaking wherever it's even lightly touched. The whole lining can be scrubbed off with ease if water is added (I just cleaned the travelpack's daypack and will get on with the main bag later today).

Normal wear and tear is scuffing, perhaps some rubbing and fraying, discoloration, getting a bit out of shape, some stitching popping eventually, a zip going boing...

We also have another backpack that has been used more often but is the same age (16) and it is showing some whitening of the coating and showing signs it will lift off, but it's nowhere near the dandruff-fest that mine was after half its age. So I would say that some breakdown in the inner coating is to be expected. What have you found, Tom?

I would not expect a daypack, messenger bag or briefcase to last forever, but the travelpack was used at most once or twice a year, and it started seriously dying after about 8-10 years - that's fewer than 10 to 20 uses - but only in this lining; everything else is still perfect. I had to get a new bag since it was unusable after 10 years, but I was hoping to resurrect this one if possible.

My main question was, really, how long is considered normal and more importantly what could be done about it. I think I have a reasonable set of solutions. A gentle scrub with a nailbrush underwater seems to allow complete removal of the lining; I will then wash with nikwax techwash and then tent&gearproof it, and sew myself some sort of raincover. I'll also not use it "bare" but get some packing cubes or similar.

[TdeF]

I have seen references to this elsewhere in the argument for using natural materials, cotton, wool, etc., but they have their own set of problems too.

[Foggy Morn]

We have two of the small cafe bags from the early 90s (when Tom was in Santa Cruz) and they are both in great shape. They don't seem to have any coatings on them, though, just the fabric they are made of (not sure what it is though I'd guess Cordura).

[Tom Bihn]

I've always considered the urethane coating on the fabrics we use to be the weakest part of all our materials. This is why I tend to design a lining into a product whenever practical, and to assemble the linings into the bags coated side-to-coated side. The Cafe Bags are an example of how well that can work: still going strong for ten years or more or use!
The urethane coating does wear off, but also simply decays over time, the so the very old travel bag that was used only a few times loosing its coating does not surprise me at all. In fact, if the bag was stored in a even slightly damp place, somewhere without much air circulation, the coating seems to go even faster - and smells pretty bad too. (Don't store your packs in a basement!)
The good news is that the coatings have improved over time, and I see less and less coatings-gone-bad.
Regarding the plan to remove the coating and use a rain cover and Nikwax, sounds like it may work OK. When it comes down to it, the coatings are really the second line of defense: hopefully some sort of durable water repellent makes the water bead up and run off so it doesn't puddle on the surface and leak through.
Further notes:
Back in the day, when Dick Kelty made Kelty packs in his garage in Glendale, California, he used uncoated nylon. Why? #1 so that your gear could dry out and wouldn't get moldy, and #2 because the coating actually weakens the fabric (ever so slightly with the newer coating processes) - he could use lighter fabric and still achieve a durable bag. He made coated nylon rain covers for his packs, which indeed makes a pretty waterproof affair, covering the zippers and seams as they did. A pretty cool arrangement but too kludge for most people's taste.
Also interesting: the other, less obvious but still very important function of the urethane coating on nylon fabric is to stabilize the cut edge of the fabric, to keep it from fraying apart. When we tape or otherwise finish all the internal seams on our bags, we do it to cover the cut edge of the fabric so it looks nice but also so it doesn't fray apart, and one aspect of that is to keep the coating on the seam allowance of the fabric for as long as possible, hidden under the binding tape or zipper tape or what-have-you. Kelty (and in the very early days, me too) would hot-cut the nylon to create a fused edge that kept the cut edge together. However, the fused edge would eventually break off and then the fabric would fray: binding the cut edge with a self-edged material (such as grossgrain ribbon or zipper tape) is a far longer-lasting solution to fabric fraying, IMHO.

[LWarren]

Hi cpau,
The Man Has Spoken, and I've got nothing like his expertise on linings and coatings, but I can tell you this: Your definition of long use poses no challenge to Tom Binh bags, in my experience. A decade ago TB sold a padded version of what's now called the Large Cafe Bag as a laptop bag. I bought one (plum and kiwi), and it has outlived three laptops and survived a tornado, and for the past six years it has been in the custody of a commuting niece of mine who carries her mac laptop everywhere, every day. I swear to you, it looks (and works) EXACTLY as it did when it first came out of the box. Nothing has peeled, frayed, popped, or broken. Seams, straps, zippers, all the parts, are still in MINT condition.
I have a ten-year-old North Face pack that's gotten a lot of use from Alaska to New Zealand, and the urethane coating has entirely flaked away, just as you describe. It's still a fine size and design, and the fabric, zippers, straps, pockets, etc., have lots of wear left, but it's not even water resistant anymore, and that limits its utility.
I'm 47, and it has recently occurred to me that my Tom Bihn bags are VERY LIKELY TO OUTLIVE ME. I can just imagine my heirs at the reading of the will, frantic to find out: Who gets the Tom Binh bags?????
I propose a toast: To eternity with cool pockets, and a strap!
Cheers,
Lynne

[backpack]

That is an amazing post Tom, the science of sewing and TB bags making.

Amazing!

[Patrick]

That is an amazing post Tom, the science of sewing and TB bags making.

Amazing!

yeah, inspires me to sew my own back pack some time ;p

[Alex Merz]

The durability of Tom's bags is no joke. Every bag of Tom's that we (Steff and I) have bought sees regular use. None has been discarded or retired. Our history, in reverse chronological order:

- Swift. A month old. Three projects done.

- Aeronaut. Almost a year, ~ 35k miles to date. So far, so good. Still looks new. Greatly facilitates my contribution to carbon emissions 8-(.

- Smart Alec daypack. ~4 years. Wonderful. No significant signs of wear.

- Cafe bag. 10 years? Good as new.

- Black courier bag. >12 years. Still used regularly and looks better than most bags do when new.

- Green courier bag. >15 years. Ditto.

- Twisted Limpet daypack. The Champion of Daypacks. The gigantic YKK nylon coil zippers are finally wearing out after some 22 years of continuous heavy use through college, on many climbing trips (think serious abrasion) and overnight hikes, though grad school and ever since. I've never subjected a bag to as much abuse (for a long time it was the only pack that I owned besides amuch bigger Osprey), and I probably never will again. This is the only bag in the bunch that has unbacked, coated cordura, on one panel. In torrential downpours it does leak through that panel. In typical Seattle rain it does not leak enough that we even think about it. We do not own an umbrella.

[PM4HIRE]

Given the high quality of workmanship, functional design, and materials used
in the production of Tom Bihn gear, you'll long get sick of looking at your bag
before it shows any significant sign of wear.

At 63 years old, I'm putting a statement in my will to gift my TB bags.

[cpau]

Thanks for all the great replies. Your stories of long-term experience with Tom's bags really helps. Thankyou also for your (long!) reply, Tom. It's never been stored in a damp place - always a well-aired cupboard (no basements here in Australia, either!) and smells fine. The lack of such drastic deterioration in another bag of the same age subjected to exactly the same storage conditions and even more use makes me suspect that material differences are the key. I'm glad things are improving over time.

I seem to have resurrected the travelpack by scrubbing fairly gently with a nail brush while submerging the bag, etc, as I described above - all the coating is gone and it looks beautiful. It took... a while. Now to waterproof it!

I noticed the anti-fray property of the coating, as you described, Tom, as I was removing it; the edges became significantly more frayable, and I had to be careful to scrub gently. The area near the zips seems to be the only place where significant fraying might occur in my travelpack because that's the only place where the true edge of the fabric is visible. As is probably common with most bags, the other inner seams (eg back joining sides, etc) are sewn over with a strip of doubly-selvedged tape about 2cm wide with a sort of diagonal-looking weave.

Thanks again; happy travelling!