Need Help Grommet placement into reinforced stitching

[Jake - Advantage Signs]

Good afternoon Signs101 - long time, no see!

Since the shop is...a bit slow right now, I've been working on SOPs for production and finishing and I've come across one of those subjects that is apparently a controversy here in our shop - where to place grommets in relationship to the webbing in reinforced stitched hem.

We use a 1" nylon webbing, and the person who does our stitching uses just a single line of stitching about 1/4" from the inside edge of the hem. The standard I train people on is to weight the grommet slightly towards the middle of the banner, so there is more webbing outside the grommet than inside, but the grommet is still fully within the webbing. Here's my SOP diagram:

Speaking with a couple of the production staff made me realize that they either forgot how they had been trained or that maybe someone that wasn't me trained them, and they will put the grommet centered in the webbing.

Do you have a standard? Where would place the grommet in 1" webbing?

(On a side note: the whole reason I even started talking with anyone about it was that I realized that I usually put the grommet in the MIDDLE of a taped hem - a hem made with 1" double sided banner tape. No idea why I have two personal standards, but I guess this is why it's good to revisit this stuff occasionally!)

 

[Boudica]

When we finish banners in house, we tape hem them. That said, I put the grommet relatively centered in the hem.
Sometimes we send banners out to be finished and then they get stitched. I've never noticed where they are putting the grommets though. Next time it comes up I should take a closer look.

 

[WYLDGFI]

IF we use webbing for our clients, we put it in the center of the webbing so not to cut through one edge or the other and keep it more intact. If our hems are just welded, the hole goes thru both layers of vinyl with the grommet top just off of center.

 

[JPR-5690]

I would think that the grommet should go as close to the middle of the webbing as possible.

The whole concept behind any sort of hemming/reinforcement - not to mention the scrim in the banner itself - is to distribute the amount of force being applied to the banner material so that the force isn’t strong enough to damage the integrity of the banner.

If you place the grommet unevenly within the webbing you’re actually creating a (relatively) weak spot in the banner because your webbing isn’t going to be able to evenly spread out the tension from the tether.

Im trying to think of a good analogy but my brain is still asleep...the best I have tight now is that it’s kind of like those little white doughnut stickers that you out on 3-hole drilled paper so that it’s not as likely to tear out from a binder. If the sticker was thicker on one side of the doughnut than the paper would still be likely to rip wherever the sticker is thinnest.

 

[Eforcer]

We hem edges with tape. But aside from just grommets in the center of hem, we also reinforce the area with another piece of banner for strengthening where the grommets are.

 

[unclebun]

Center of hem, center of webbing.

 

[tulsagraphics]

I've tried a variety of methods over the past 12 years. These days I change the grommet position depending on the size of the banner and how it will be installed. There's a good chance that if I'm going to put webbing into a banner, I'm probably also using 18oz smooth face. (Ultraflexx 1k/1.2k denier 13oz/18oz is awesome -- my banners seem to last "forever".)

For a customer that wants that wants extra grommets (to fit inside a metal frame, for example) -- I'll place grommets dead center in between the stitch lines (which, in my case is .5625" from the edge b/c my folds are 1.125" wide, so technically there's a tiny bit more webbing on the outside edge). But if the customer plans on using zip ties and T-posts with 4 corner grommets (long term use, or just a general assumption that the customer isn't going to install properly), then I'll place the grommets inside the inner row of stitches -- where the grommet neck is about 1/16" away from the inner seam so the washer can "grab" without actually cutting "through" the seam/webbing. About the only time I actually punch "through" my stitches is when the customer requests banner-up tabs (just because of the banner-up hole placement).

Many years ago when Fellers was offering hem services, they used to just put everything dead center of the webbing. Eventually they moved the grommet placement to the inside of the inner seam because their customers were reporting better durability -- so I adopted that method, for the most part, when I started sewing. That being said... they were also using polyweb at that time (which also shrinks too much after weathering -- yek!), so maybe the thicker polyweb was just too much to deal with anyway (possibly too much "scrunching" from the grommet press).