Deconstructing a zippered pouch

Posted by Stuart Friedberg on Oct 8, 2008 at 5:00 am / Sewing, Tutorial / Trackback

I am doing a building project, and as I was sitting at my kitchen table with the construction manager, he asked me if I could replace the zipper on a tobacco pouch.

Tobacco pouch with a dead zipper

Tobacco pouch with a dead zipper

I accepted the challenge, mostly to generate a blog entry or two. In this entry, I will take the pouch apart, finding some surprises even in a simple sewn product like this one, and show some variations on this pattern. In a later blog entry, I will put the pouch back together, showing some tools and techniques for sewing difficult materials.

Items like this zippered pouch are constructed inside-out. Most or all of the seams are sewn with right sides together, then the whole thing is turned right side out at the end like a collar or pocket flap. As it turns out, the zipper was the very first thing sewn, so we have to take the pouch completely apart to replace the zipper.
Pouch turned inside out

Pouch turned inside out

Not being a smoker, my first surprise was that the pouch is lined in latex rubber. A nasty nicotine color after years of use, this rubber lining keeps the pipe tobacco from drying out, smelling up the place, and staining the leather exterior. The final seam, and the first one we will rip out, binds the two body halves together with a plastic strip. This plastic is not a woven material; it’s embossed with some sort of texture, but it’s a solid material. It is also dried out and cracked, and will have to be replaced.
First seam removed

First seam removed

After removing the stitching and old plastic binding, the edges of the body were still stuck together. I was afraid they had been glued with something I would not be able to remove. As it turned out, the leather right sides and latex linings were only sticking to themselves with natural adhesion, and they could be easily pulled apart. Two things became clear at this point.
Padding and latex layers lining the leather exterior

Padding and latex layers lining the leather exterior

First, the latex lining does an excellent job of keeping the staining and odor from exiting the pouch. The lining side adjacent to the leather is unstained, so nothing is getting through. Second, there was an additional layer of padding between the leather exterior and the lining. It is now totally worn out, but it looks like a thin layer of open cell foam.
Looking for the next seam

Looking for the next seam

Close examination of the remaining seams reveals that the body halves were sewn to the zipper as the second-to-last operation, so those will be the second seams we rip out. They were sewn on a double-needle machine, so there are actually four lines of stitching to remove to separate the body pieces from the zipper. These seams were glued before stitching, but fortunately the glue was something like rubber cement and easily peels away without damaging the leather. We also find that the leather exterior was cut longer than the lining, and the excess has been glued to the top edge of the lining as a clean finish hem. I will leave the leather and the lining attached along this edge.
Separating the second seam

Separating the second seam

Second seam removed

Second seam removed

The first seams to be sewn, and the last ones we rip out, attach the zipper tape to leather tabs that make up the rest of the open side of the pouch. The tabs are unlined, but like the body pieces they have been folded over and glued to the zipper tape before stitching. Only a single line of stitching attachs them to the tape.
Separating the third seam

Separating the third seam

Pouch completely taken apart

Pouch completely taken apart

Distortion of the zipper teeth

Distortion of the zipper teeth

We can now see the distortion of the zipper which caused it to fail. If you are doing seasonally-focused apparel, the long term durability of your garments may not be an issue. But for work clothing, equipment bags, tool cases, and similar items, examining the ways in which they wear out can suggest ways of improving the design for longer lifetimes. In this particular case, I have two observations. First, the edge of the body pieces that attach to the zipper take were almost certainly straight when first cut and sewn. Over the years, this edge has stretched so it is now longer and curved. Second, there was clearly a concentration of stress at the two ends of the zip travel, especially at the closing end where the zipper teeth are almost pulled out of the tape. A redesign that reduces this stress and accommodates the material stretching would be an improvement.

Before closing, I’d like to show some variations on this simple zippered pouch. They won’t win any prizes for style or finish, but these pouches were quickly cut and sewn to store specific contents.
Microphone pouches

Microphone pouches

The tobacco pouch was flat, like an envelope; the zipper was one creased edge. These pouches both have some depth, like a bag with four sides and a top and bottom, but they get it in different ways. They also have seams that, like hems, go all the way around. The tobacco pouch has no such seams, the upper microphone pouch has one, and the bottom microphone pouch has two. Both microphone pouches extend the width of the zipper tape to form one side of the pouch, then extend the length of the result. The top pouch wraps the “big zipper tape” around three sides of the pouch, with the remaining sides provided by a single pattern piece. The bottom pouch wraps the “big zipper tape” completely around the middle of the pouch, forming four sides of the pouch, with the remaining two sides provided by separate pattern pieces.

We had a number of microphone cable spools that needed storage.
Lavier microphone cable spools

Lavier microphone cable spools

Pouches containing cables and other gear

Pouches containing cables and other gear

The pattern for the one on the right was sized to hold two of the circular spools, while the pattern for the one on the left was sized to hold three oval spools and some loose adapter cables. Before I forget, these were “interfaced” with cardboard glued to the interior to give their sides some rigidity. Is there such a thing as bas couture?

This is definitely not to scale, but will show you the pattern and sewing differences among these three zippered pouches. Again, they are all sewn inside out, and turned rightside out as the last step.
Tobacco pouch sewing order

Tobacco pouch sewing order

Oval spool pouch sewing order

Oval spool pouch sewing order

Circular spool pouch sewing order

Circular spool pouch sewing order

A future post will cover replacement materials and putting everything back together again.

Related:
Process review: lapped zipper
Lapped zipper template
Lapped zipper construction
Lapped zipper specs
Centered zipper template
Centered zipper construction
Invisible zipper tutorial pt.1
Invisible zipper tutorial pt.2
Shorten a separating zipper
Zippered welt pocket tutorial
Deconstructing a zippered pouch
Zippered welt pockets

11 Responses to “Deconstructing a zippered pouch”

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Valerie Burner
October 8th, 2008
8:46 AM

Great article! I love seeing how things are put together- especially older things with unusual uses. The graphics are amazing as well. The cable pouches are really cool. Are those pouches your design? I wish I had a pouch for everything- think of how organized it would be!

kay
October 8th, 2008
9:26 AM

Stuart, thank you — the diagrams at the end are wonderful. I’ve got a beginning home sewer who is having trouble with standard home pattern instructions, but I think he’ll comprehend your diagrams instantly! Genius!

Vesta
October 8th, 2008
10:15 AM

Thanks so much, Stuart. I love this! One question: when/why does one glue seams before sewing? Does it have something to do with thick materials, like leather?

Dennis
October 8th, 2008
10:44 AM

This reminds me of a time at sewing class when some male classmate showed up with a deconstructed Beanie Baby. The pieces consisted of small white plastic beads and fabric printed on one side with the other being white. The SAs were 1/8″. Would be curious as to type of machine used. Don’t know if he ever reconstructed it back the way it was.

Stuart Friedberg
October 8th, 2008
11:13 AM

Valerie — Yes, the cable pouches were whipped up in an evening to fit the contents. We made the cardboard spools (which owe more to tinsmithing than sewn products) at the same time. The trickiest bit, and the part I would tweak if they were going into production, is getting the seamlines on the pattern pieces meeting at all-the-way-around seams exactly the same length as sewn. These quick and dirty pouches came out pretty close, but I had to do a little bit of cheating (easing, actually) to close the seams and that should be fixed in the pattern.

Vesta — A good question for which I have only a partial answer. Kathleen can probably tell us lots about glueing leather. Glue is usually inappropriate for pervious materials like cloth, so you would find it used on things like leather or plastic or plastic-coated materials. On the other hand, it’s not unusual to find strips of fusible web being used to baste or hem, even on very fabrics.

Glueing the seams (in the seam allowance only) is good for at least two things: basting and sealing. In part 2, when I put this pouch back together again, I will be using rubber cement for both reasons. Contact cement or some other permanent adhesive can also be used to “finish” seams by glueing the seam allowance to the wrong side of the shell, and in some cases (lap seams) could even be the primary means of creating the seam.

Shermane Fouche
October 9th, 2008
4:37 AM

Thank you, great article and great design for the pouches, cable holders. I travel alot and need to be able to have things organized rather than to just pitchfork my stuff into the suitcase.

Zaz
October 9th, 2008
8:29 AM

actually yours do look nice, it’s that offwhite fabric and the custom made sizes that take us away from the old “uggly” original.

Lisa B. in Portland
October 9th, 2008
9:54 PM

Very cool, Stu!

I made a zippered handbag for myself and some handbags with 1 zippered pocket, but all the other handbags and tote bags I’ve made don’t have zippers.

I don’t ever seem to be that excited about putting in zippers. Maybe I need someone to hold my hand during the process and tell me it’ll be ok. Heh heh. :-)

Marie-Christine
October 10th, 2008
1:09 PM

Oh, thank you, it makes so much sense to relieve stress at the ends of the zipper by not having those end at precisely an angle of the pouch. Definitely also good advice to observe the wear pattern in order to design around it for the next revs..

Michael M.
October 11th, 2008
6:48 AM

More, More, More, More!!!!!

Thank you, very, very much.

robbie
October 22nd, 2008
9:36 AM

who doesn’t like great, direct and point specific advice on how to reconstruct an item even better than before. can’t wait to try it out for myself. thanks, rob

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