Sewing on #3 zipper with sharp turns

Before you commit yourself to this design, I thought I’d pass on my own research into zipper reliability.

The great majority of reported zipper failures in the field seem to involve curved zippers. The curves seem to put greater strain on the teeth. Many people reporting failures claim that they are careful with their gear and weren’t abusing the zippers – you’ll have to make your own judgement about whether this is credible.

Personally I prefer two zippers in an inverted V, from the top to either side of the bottom. This does leave your door on the floor, but it can be tidied away with a couple of ties. I’ve used this arrangement for decades and never found it a problem.

The other straight-zipper design is the inverted T. This involves a third zipper and is a bit more hassle to open, but does keep your door off the floor.

Either of these will be easier to sew than a curved zipper, and will be less likely to let you down in the field.

Oh – and there’s a third straight zipper door design that can work for smaller doors – a sideways V with a zip along the bottom and one side. This keeps your door off the floor.

The advantage of the inverted V is mainly for double doors with a bug net and solid draught excluder. With the inverted V you can close the bug net fully and have the draught excluder at any level you choose.

A good video on what Samsung are up to in this field – their research results were published in Nature which suggests they are on to something big. But they’re still a year away from  commercial release:

https://www.youtube.com/watch?v=Go2g_BNpG_Y

I’m trying to envision how 2 zippers can leave an opening where they come together. I know that question may not make sense. Explain please.

So maybe cut ends of zippers at a 45 degree angle?

When I’ve done curved zippers for a door, I start at the top, sewing the straight piece first, and then use a lot of pins for the curve. I’ll only sew a couple inches at a time before adding in more pins. This works okay. What have you tried that was a disaster in the past?

I think I’ll go for an L-shaped zipper next time with two separate zipper tracks. Saves weight over a whole inverted-T. And I agree with Geoff on curved zipper strain – the curve is always where my zippers end up having the most trouble.

You can do a sharp 90 degree corner and treat it like two separate zippers, with a slider from each end meeting at the corner, but never actually going around the corner.  This is easier to sew than two, separate straight zippers, but leaves the little hole where the sliders meet at ground level, closer to creepy crawlers.

If you want to be able to use a single slider, ask yourself how far in to the corner do you really need the opening to go, and keep the radius of the curve as large as possible.  Cutting the panel with the zipper so it has a lower tensions will reduce zipper wear.  If you’re careful with your panel design, you can keep low tension on just the area with the curved zip in it.

Oops – I’ve posted above on the wrong thread – please ignore. Removal of the edit option is a real pain…