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Abrasion in back of Pilot

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  • bb93fo57
    replied
    Originally posted by Darcy View Post
    Interestingly, we have found that sun exposure, high humidity and air pollution can speed up the process of the urethane coating wearing off.
    Thanks for the info, Darcy.

    I have a feeling that rubbing against sharp-edged contents of a bag can contribute to it, too.

    I have been using using a Q-kit to stash my keys, and found that taking the keys in and out multiple times/day caused big chunks o' the urethane coating to peel off pretty quickly.

    Fortunately, haven't had that happen to any of the travel or EDC bags. I stopped carrying spiral notebooks in my Pilot in hopes that eliminating the metal spiral rubbing against the Dyneema would prevent decay of the urethane coating in that area.

    YMMV, as always. :-)

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  • PandaOps
    replied
    For those with this issue, how long have you owned the Pilot for? I'm considering a Pilot for my work carry.

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  • Darcy
    replied
    As tpnl noted, it looks like the urethane coating is wearing off. To add to the great answers/information already posted here:

    Most of the fabrics we use are coated with a thin layer of urethane plastic on the reverse side of the fabric (typically, the inside of the bag). This coating, combined with the DWR (durable water repellant) treatment on the face (exterior) of the fabric helps keep the worst of the weather away from the contents of your bag.

    Relative to the longevity of the fabric itself, as well as the other components of the bag, both the urethane coating and the DWR treatment might fail earlier than we'd prefer. Over time and use, the DWR wears off of the surface of the fabric: it's invisible, so you can't tell that it's gone until you start seeing surface water soak into the cloth itself. We sell Nikwax® Tent & Gear SolarProof® as an after-market, applied-at-home treatment that allows you to more or less renew the original water repellency of the fabric (you can find Nikwax® at most outdoors stores so if you're not already buying something else from us you may just want to pick it up locally.)

    The interior urethane coating, however, is more problematic, in that there isn't (so far) any good way to renew or treat areas where the coating has worn away. We work closely with our fabric mills, and when we show them bags that have had their interior coatings wear away, they shake their head and say "yep, that happens sometimes". They offer no help or recourse for us, and so far we have found no acceptable alternatives.

    It's worth noting that fabrics made in countries without many environmental regulations may be coated with more durable coatings than the fabrics we use that are fabricated in the U.S. or Japan; we choose a slightly less durable coating over something that could be considerably more toxic to our planet and us humans.

    That all said, we have had an occasional roll of fabric that seemed to have had particularly not-so-good coating, in which either the thickness of the coating or its adhesion to the base fabric was less than optimal.

    If anyone has a bag that has had the coating substantially fail within the bag's first year of use, we might be able to replace the bag entirely if it's adversely effecting your use of the bag -- [email protected] if that's the case and we'll work the details out.

    P.S. Interestingly, we have found that sun exposure, high humidity and air pollution can speed up the process of the urethane coating wearing off.
    Last edited by Darcy; 09-08-2015, 10:15 AM.

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  • DeBru
    replied
    Is it possible that it is heat damage to the coating, perhaps from a hot battery on a laptop or tablet? FWIW, I definitely would not use an iron on patch, the temp needed to fuse the glue would very likely melt the nylon. Maybe try using a small craft paint brush and apply a clear, strong glue? something like Liquid Stitch that adalangdon mentioned.

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  • saikyo
    replied
    I have the same problem and posted about it in another thread.

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  • tpnl
    replied
    Based on what I understand:

    Essentially, to make a bag waterproof, there is usually a multi-layer protection approach used. You need to protect the bag fabric from getting wet (and shrinking), protect the inside contents and make sure water does not get throught seams and zippers.

    The urethane is only one part. It is a permanent part that is used to protect the inside of the bag. However, it cannot cover seams, zippers or the outside fabric itself
    So, to answer your question, the urethane provides most of the waterproofing between the outside fabric and the inside of the bag but misses the seams and zippers.

    The nikwax waterproofing spray is another part and is the first barrier that keeps water from soaking the fabric and getting though the seams. However, it is temporary as it wears off and needs to be replenished.
    So, to answer your question, a bag without the urethane layer can still be waterproofed via the waterproofing spray. However, this is temporary and needs to be reapplied as you brush the waterproofing off the bag in normal use.

    The YKK zippers esnsure the zipper part does not allow water in.

    Bag design is important for waterproofing - ie - physically designing no places where water can pool (e.g. the fabric zipper covers on the Brain Bag, how the connection points between zippers and bag fabric are sewn, no open top pocket sections of the bag, streamlining bag so water flows off when sitting normally). This is where the years of experience that Tom Bihn and his crew have really shines.

    Finally, material choice is important too. Ballistic Nylon / Cordura are a good balance of strengh and quick drying. For example, Polyester is better for drying faster when wet but is not nearly as durable or strong - Cotton - takes a long time to dry. Dyneema is fairly well waterproof because of the way it is designed.

    I may have missed other factors so others, please add in.

    Hope this helps
    Cheers!
    Last edited by tpnl; 10-02-2014, 09:50 AM.

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  • icebeng
    replied
    Quick question: how much of the waterproofing is provided by the urethane layer?
    Would a bag without the urethane layer be totally susceptible to rain?

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  • tpnl
    replied
    Don't laugh ... what about duct tape? There are ones that are black in color and it will keep water out pretty well. Cutting a small round patch would work.
    Also, getting a tent patch kit should work...after-all, the Nikwax is for tents and gear.

    Hope this helps!

    Cheers!

    Leave a comment:


  • adalangdon
    replied
    Originally posted by icebeng View Post
    Is there such a thing as safe fabric glue? That might work better.
    There's Liquid Stitch, which came to me highly recommended but doesn't help iron-on patches stick better, or so I found. The problem lies with the iron-on backing-- it's smooth and will not let something as wimpy as fabric glue bond to it. That's why when I try to stick decorative patches onto cordura, I first attempt to strip off the backing (sometimes you just can't), then glue + sew.

    I'd be very interested to know if there are stronger fabric glues out there!
    Last edited by adalangdon; 09-29-2014, 08:10 PM.

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  • icebeng
    replied
    Is there such a thing as safe fabric glue? That might work better.

    Leave a comment:


  • adalangdon
    replied
    Originally posted by bchaplin View Post
    Oh, I see. Thanks. I misunderstood.
    Maybe I could get an iron-on patch (like the kind you use for jeans; I don't even know if they are sold anymore), to prevent further fraying.
    I would be extremely careful with iron-on patches! Maybe the ones I've worked with sucked, but you need to whack those things with an iron at the max (i.e. cotton, linen) setting to get them to stick. That would only be really okay if you were ironing onto cotton fabrics. I think. Someone with more experience will know better.

    Leave a comment:


  • bchaplin
    replied
    Oh, I see. Thanks. I misunderstood.
    Maybe I could get an iron-on patch (like the kind you use for jeans; I don't even know if they are sold anymore), to prevent further fraying.

    Originally posted by tpnl View Post
    Just to clarify - the issue in your pictures is is not the Nikwax waterproofer IMHO. In each TB bag (that I know of), there are 2 things done for waterproofing.
    On the exterior, the Nikwax is sprayed on so the fabric does not get wet and needs to be recoated every so often. The urethane is something different. It is permanent and acts as a second waterproof barrier between the fabric and the inner contents (as opposed to a barrier between the rain and the fabric which is the job of the Nikwax).

    See this part of the TB Faq on waterproofing: TOM BIHN: FAQs

    Essentially, there is no good (read permanent) way to recoat the urethane - you can buy some urethane spray I think and recoat it but it tends to flake off after a while (this is what I have been told).

    Hope this explains things a bit better.

    Cheers!

    Leave a comment:


  • tpnl
    replied
    Just to clarify - the issue in your pictures is is not the Nikwax waterproofer IMHO. In each TB bag (that I know of), there are 2 things done for waterproofing.
    On the exterior, the Nikwax is sprayed on so the fabric does not get wet and needs to be recoated every so often. The urethane is something different. It is permanent and acts as a second waterproof barrier between the fabric and the inner contents (as opposed to a barrier between the rain and the fabric which is the job of the Nikwax).

    See this part of the TB Faq on waterproofing: TOM BIHN: FAQs

    Essentially, there is no good (read permanent) way to recoat the urethane - you can buy some urethane spray I think and recoat it but it tends to flake off after a while (this is what I have been told).

    Hope this explains things a bit better.

    Cheers!

    Leave a comment:


  • bchaplin
    replied
    If it works, I will.


    Sent from my iPhone using Tapatalk

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  • GoStanford
    replied
    Originally posted by bchaplin View Post
    If it is just the coating and not the fabric I don't mind. I can respray it, since I have Nikwax. It is unlikely to have come into contact with the chemicals you mention, but who knows?
    Can you post a Nikwax tutorial for those of us who have never used it? I have never gotten a bottle but I can see needing it down the road for maintenance.

    Leave a comment:

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