Sewing Cuben

[andrewa]

To date, I've used how tape for my simple cuben projects, such as stuff sacks and roll top bags, but I've not tried to sew it yet.

Has anyone some advice about sewing? Specifically interested in needle size and point type, and stitches per inch. I'm about to make a raincoat, which can mostly be glued, but I will to sew a few bits.

A

[Mark F]

I get the impression that you need a fine needle depending on the thread. The thread has to pass freely through the eye of the needle. No more an about 8 stitches per inch (3mm stitch length).

I am planning on taping the seam then using a coarse 3 stitch zigzag like the sail makers. (3 stitches on each zig and zag). Bgr - HTML gets rid of the extra spaces.
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[simonm]

Andrew - there is this link http://hikeitlikeit.com/2012/cuben-fiber-roundup/ which has this relevant info:

Just to provide some perspective on what it’s like to work with Cuben Fiber I asked Judy Gross of LightHeart Gear about it. She offers some insight that DIYers, or anyone really, may find interesting.

“Cuben fiber provides a number of different challenges when sewing due to the selection of many different weights of the fabric. The very lightest cuben, will crimp and crumple up, while the heavier cuben will be stiff and drag at the machine. Any mistakes in sewing will leave permanent holes in the fabric, though these can be covered with tape.

Cuben will quickly dull machine needles as well as any cutting tools used. When sewing tents, I use thread that is stronger then general sewing thread and a longer than usual stitch – the less holes poked in the fabric the better. But, the combination of strong thread and long stitch on lightweight fabric causes issues with tension and difficulty in getting a seam to lay nice and flat. To achieve this, you have to use a “taut sewing” technique by gently pulling the fabric from the back of the presser foot.

I use all industrial sewing equipment, my machines have ‘pullers’ (this is a highly technical term) to help achieve a flat seam. A puller is a roller that clamps onto the fabric as it comes out of the presser foot; it is geared to the stitch length and ‘pulls’ it out so the stitches lay flat.

I like to tape any cuben to cuben seam after sewing it. I find the needle holes will grow a little when tension is put on the seam, so I reinforce each seam after sewing with cuben tape. When sewing over seams that were taped or glued, the machine needles often get gunked up from the glue, this is easily remedied by cleaning the needles off with a little rubbing alcohol.”

[Son of a Beach]

Bgr - HTML gets rid of the extra spaces.
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Put it in 'code' tags ('code' button above the full editor text area) to get it treated as 'pre formatted' text. Like so:

Code: Select all

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[Orion]

HTML gets rid of the extra spaces...

Put it in 'code' tags ('code' button above the full editor text area) to get it treated as 'pre formatted' text.

Alternatively, you can use the "Font colour" button to produce characters that are essentially invisible as a way to pad.
For example:

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[Mark F]

Thanks for the tips.

[Orion]

Another approach is to use images, either of a drawing or an actual object.

Triple step zig-zags on a tent seam:


Triple step zig-zags on a Cuben sail (the white threads):


Here's what a sailmaker had to say on BPL (link):

This is an interesting topic but there are some broad strokes being painted about sewing vs bonding.

I am a sailmaker at North Sails and one of the only sail lofts in the world that builds Cuben spinnakers. They are 400 to 900 square meters in size and cost up to $180,000 each depending on size and cloth (cn 5 up to cn18) used.

We sew all Cuben spinnakers. The seems contain both 3m (9485) double sided tape and sewing. We have never had any failures yet, with our sails competing in the worlds most difficult offshore races. We have in the past seen failures when sails were constructed using Q-bond only.

My point is that if you use a small needle (size 90) and light thread (v32) and triple step stitch it shouldn't tear the cloth, and if it did the nature of Cuben would stop it from yielding. Ryan's picture at the top of the thread look like a larger needle was used and zig zag stitch creating nice holes to yield under load

So depending on application, I think there is merit for both methods of construction...

...Most/all tarp shelter manufactures don't use cuben properly as say sailmakers who design spinnakers around the load put on the warp direction of the cloth. Most tarp are constructed with the least amount of seems to save weight and cost in manufacturing (ie :less cloth and build time). They usually run the ridge line along the warp of the cloth and simply join 2 pieces together...

...But in fairness, we are talking about comparing how industrial/commercial construction techniques differ from say home building. Some techniques can be used and some can not. Clearly loads are not that great that in tarps that require techniques taken from sailmaking.

I had a look at my sewing machine. While it has a number of weird zig-zag and stretch stitches it can't do that one.

[simonm]

Hi Andrew not sure how far you have progressed with your sewing but recently I purchased a custom made Zpacks pack off another forum and it came with 2 cuben dry bags which are stitched and taped. The tape going over the stitching on the inside of the bag.

[andrewa]

Simon, haven't sewn anything yet...we've had a few things "on" at home. The taped dry bags appear fine. Sewing and taping would also work, but I'm happy with them just being taped, as there's not much load on the seams. Am planning to tape the seams on the jacket when I make it too...

A

[simonm]

Hi Andrew,

I am going to have a play with some cuben soon, so will try sewing and taping. Looking forward to seeing your jacket.

[ofuros]

Me too....Hopefully, while on R&R at home over the next 2 weeks, I''ll find some time to make up a cuben tarp.

Just got to replace the back stair treads, fix the rotted out guttering, spend some quality time with my wife & young'n,
fit in an overnighter @ Spicers Gap and go for a exploratory trout fishing trip in Nsw...I don't like my chances...but my fingers are crossed.

[simonm]

Me too....Hopefully, while on R&R at home over the next 2 weeks, I''ll find some time to make up a cuben tarp.

Just got to replace the back stair treads, fix the rotted out guttering, spend some quality time with my wife & young'n,
fit in an overnighter @ Spicers Gap and go for a exploratory trout fishing trip in Nsw...I don't like my chances...but my fingers are crossed.

Hey mate,

What's your plans with the tarp? Sew and tape, or just tape?

[ofuros]

A few tieout test pieces first, with just tape & titanium d rings...if the area doesn't handle the stresses too well,
I will just sew & add some staggerered layers of cuben around that area for piece mind.
Hope I dont run out of tape half way through the project !

.....via tapatalk.