Training new sewing operator pt.3

This is part three in the new experiment of training a new sewing operator. It was first described here with pictures posted of the results. Part two consisted of commentary from the trainee. This entry describes our second experiment, again sewing the very same item, a fully lined zip front vest with welt pockets. The step by step process illustrated with photos is posted in the forum. For all intents and purposes, this one came out as well as the last one.

The decision to repeat the exercise with the same item was simple. You want an operator to gain confidence and competence as quickly as possible. This only happens with repetition and experience. Eric’s (the trainee) comments come first. Mine follow and include troubleshooting the cutting of slippery fabrics.


Eric:
This isn’t about sewing, it’s “pattern transfer and project management.” I think students will benefit from this shift in perception. (I’m told this is the same for welding: most of the work is in preparation, the actual application of heat is relatively minor.) The break down is:

  • Pattern transfer – 40%
  • Project/process management – 40%
  • Handling issues – 10%
  • Sewing – 10%

Kathleen constantly harps on pattern accuracy as the most critical factor and as an engineer, it I get it but it’s another thing to experience it directly. 1/16 of an inch error in the pattern, another 1/16th in transfer, another in cutting, pull a few fibers loose while handling the piece, and another in sewing the seam, and now you’re up to 5/16″, which is more than the 1/4″ seam allowance alloted for outside seams. Of course, they don’t all work in one direction; some shrink and others enlarge the piece, but it’s worth worrying about each 1/16″.

The whole thing is kept together by friction! There aren’t any chemicals (glue), we didn’t fuse the fibers together with heat, it’s just friction. Friction keeps the woven fibers together, and friction keeps the seam thread in place. Just loosen a few of those threads in the seam allowance and the whole thing can come apart. Protecting those edges inside the lining serves as more than just an aesthetic purpose. From an engineering standpoint, sewing (joining by friction) is unusual. Most products are joined by bonding (chemically etc). That explains why it’s both difficult and necessary to control variances in sewing.

I’m getting to the point where I can anticipate what is coming up. What’s more important, I can anticipate what is going to give me trouble in the next step. Here’s the outline of the process as I understand it.

  1. Transfer
  2. Cut out
  3. Fuse
  4. Pocket
    1. Use jig to create creases
    2. Mark (1″ from ends, 1/4″ from sides)
    3. Center over drilled holes
    4. Sew lines (one side at a time, over the outside of the front shell)
    5. Cut opening, end 3/4″ from ends, take to corners (not past!)
    6. Invert & press
    7. Sew tabs
    8. Sew pocket bags (1 to top welt, 1 to under welt, then together)
  5. Contrast to lining
  6. Shell shoulders and collar
  7. Lining shoulders and collar
  8. Zipper
  9. Collar and bottom hem edges
  10. Arm holes (part)
  11. Bottom (part)
  12. invert
  13. Finish other side
    1. Side seams
    2. Arm hole
    3. Bottom
  14. Near side
    1. Arm hole
    2. Bottom
  15. Top stitching -Complete

A complete success on the first attempt is a wasted opportunity. It’s only when you have a problem that you can learn something from it. You want to make all of your mistakes under the eyes of your teacher so that there aren’t any left to make on your own.
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A fully illustrated bagging a vest sewing tutorial is posted to the forum.
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Kathleen:
Eric didn’t mention a lot of things we talked about. He liked this project more than the first one. It was owing to more than confidence, I think he liked working with these materials better (55/45 Linen/Cotton). The lining was heavier, thus easier to work with. I think he also liked the colors better too. Overall, he was much more pleased with this vest than the first one.

I had the opposite reaction. I was less pleased with the results of this project over the first (one reason I didn’t post this right away). Not that I didn’t like the colors and materials but that doesn’t matter for our purposes.

Regardless of how this comes out, I’m not blaming Eric (and at least he knows that). I should have kept a closer eye on things. Because I kept a looser leash this time around, I didn’t monitor things I should have and I know better. I see problems the second time around as the trainer’s (my) failure.

We had a different problem with lining this time. Once the vest was bagged, the lining in the upper shoulder was too taut, restraining the shell in that area. Maybe not everyone would notice it but I didn’t sleep that night. In retrospect, the problem was in cutting the lining. There are several issues with cutting linings.

Lining is slippery and wants to run, slipping away from the blades. I noticed this too late. A partial solution was a pair of scissors with different blades.

Lining can be difficult to cut on grain. Normally I think people worry about grain inordinately but not so with slippery stuff. It is common that one portion is correct but as the goods skate around (perhaps with the pressure of tracing or pinning), a reciprocal side is shüeco [(pronounced “shwecko”). Sorry, I don’t know the word in English. Crudely, it means off-kilter, or crooked but incompetence or carelessness is also implied.] In this case, Eric had to cut around some holes in the fabric (bugs got to it but hey, I’ve got 15 yards of it!) and because I wasn’t watching as closely as I should have been, I don’t think the patterns were traced or cut as well as they should have been -much less on grain. A trainee couldn’t know when, why or how that matters. Like I said, I was overconfident in my trainee based on his increased enthusiasm, desire for independence (no micro-managing, that’s a confidence killer) and increased confidence. As a trainer, it’s hard to know where to draw the line. In the end, we decided it was good to have made this mistake at this juncture. Our next lesson will open with this.

An aside on cutting slippery things:
In the normal course of affairs in a production environment, you usually don’t have to worry about goods skating around because fabric plies are stacked. Either friction or weight keeps goods intact while you cut. Not so if cutting one layer or two. In my bias experimentation phase, I found the only way to reliably cut on the bias (remember, the fabric wants to slip away cutting off grain) was with weight. Now, if you’re cutting, you can’t always have a weight adjacent to the edge you’re cutting but I’ve found that firmly anchoring and stabilizing the nearby cross and straight of grains, goes a long way toward maintaining cutting stability. Eric was skeptical -like anyone would be- but was very surprised when he saw how well this worked. I put weights (use the longer pattern weights) off to the sides of the piece he was cutting, giving him plenty of room to cut and cutting was effortless. No more fabric slipping off into the nether lands. I’ll be sure to photograph how this is done next time. This is another reason quality tools are a must for professional results. Sure, in most cases you can get along with the little round weights but for things like this, the longer flat weights are irreplaceable. I have weights in many lengths, the longest being 60″. I really like the 12 inchers and wish I had more of those. These aren’t expensive but the weight of them increases shipping costs.

Machining difficulties:
Another problem we had was in top stitching. For some reason (I’ve been meaning to ask in the forum but I guess here is just as well), when Eric was top stitching along the zipper, the fabric wasn’t feeding evenly coming to such a point that a little tuck was sewn in. I had to take it all out. I don’t know why this is. It wasn’t Eric’s handling, I had to fight the same thing when I was top stitching the first project (I top stitched that one). I haven’t noticed this problem using my Mitsubishi and of course, I wouldn’t on the walking foot which is what I usually use for thick layers but this vest was lighter weight than the first and using the walking foot seemed like overkill. I’m baffled. Of course my first thought is that I have the perfect justification to acquire yet another machine, specifically a needle feed, -now I hear my not so inner child screeching “but I NEED it!” in the background- but it doesn’t sit well with me. You can’t build character by sating the whims of a four year old on demand, especially if you’re the four year old. (But I NEED it! I do I do I do!). This reminds me why I don’t do knits. Then I’d “need” a whole new set of machines like a coverstitch, flat lock etc.

The last thing I didn’t like with this vest is that because the shell was so lightweight (maybe a 7 oz), the extra large pocket bag was obvious. Well, obvious to me. There was some pooching going on in that front corner of the lower vest pocket area. This means I have to amend my previous advice on pocket bags to include the caveat that shell weight must be factored into the equation. So in the end, what I really didn’t like was having to admit I was wrong after that long spiel I wrote.
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Personal:
In the event I fail to mention it, Eric and I are taking off early tomorrow for Mexico City. We’ll be back on Tuesday. I suspect I won’t be able to log on in the interim so I can’t approve your comment if it is held for moderation. Please disregard any spam comments that may make it through the filters in my absence.

Related:
Training sewing machine operators pt 1
Training sewing machine operators pt 2
Training sewing machine operators pt 3
Training the green sewing operator
Comments from the sewing trainee
Training new sewing operator pt.3

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7 comments

  1. Todd Hudson says:

    When sample cutting, why not use underlay on bottom and/or marker paper on top for slippery fabrics? This has helped me a bunch for cutting linings and knits. It allows you to use your knife edge scissors too without slippage because the paper makes the slippery fabric stay in place. It’s either mechanical friction and/or static electricity. A sample sewer I hired encouraged me to cut like that because the first bundle of silk and polyester shirts I cut for her were cut so sloppy.

  2. Lisa Bloodgood in Portland says:

    My aunt told me to put an old sheet over chiffon when you’re cutting that, so would it work for other fabrics? Then you wouldn’t dull scissors by cutting thru paper.

    Have fun in Mexico City!

  3. Todd Hudson says:

    Cutting fabric can also dull scissors. I’d rather spend a few more dollars per year to have my scissors sharpened more often than to have my sewers resent me. The best piece of advice I got last year was to “find a good contractor and give them lots of love and they’ll give you good service in return.”

  4. Marie-Christine says:

    I agree about the small weights not being the thing all the time. But that’s when the library comes in handy :-). A good dictionary will stabilize quite a bit of fabric at once.. and there’s a lot more where that one came from, in my house :-).

  5. marie says:

    Hi Everyone,
    I am currentyl a trainee teacher here in th UK hopnig to teach pattern cutting here in the uk. I love the forum.

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