Straight Stitch

[Morgoroth]

When making a gathered end hammock where the weight will be supported by the sewing for the channel (for use with a spreader bar etc.) is there a certain stitch that works better than another?

Or is it just about running multiple passes of a straight stitch?

[Ramblinrev]

I am confused as to the seemingly pervasive sense that the straight stitch is some how an inferior stitch for weight bearing applications. In fact, I would argue the straight stitch is the strongest stitch for these applications you can get. The straight stitch, when sewn on grain is allowing the fabric itself to handle the stress of the load. The fibers of the weave are being held together by the stitch but the weave is bearing the load force. Contrary to the zigzag which is a bias directional stitch and stretches as the load changes dynamically. That stretch is born by the stitch, not by the weave. Other stitches, mostly designed for stretch and knitted fabrics are obviously not intended for these applications.

Do not be afraid of the straight stitch. It is your friend. The multiple passes add nothing to the strength of the seam line. Rather they serve as a redundancy line so if one line should happen to break other lines will hold. This gives the opportunity for visual inspection to catch the failure before it becomes catastrophic. Embrace the straight stitch. It is your friend.`

[Hiknhanger]

I knew Ramblinrev would come to the rescue on this topic! I kept silent in deference to the master!

I am a big guy, and I made my DIY hammock end channel with three rows of straight stitching. It works great. I have done whipping knots with Whoopieslings larksheaded around that on my prior ones out of fear the stitching would give, but there is no problem.

[Morgoroth]

That makes a lot of sense, and its good to hear, considering that my machine only does straight stitches.

It was my grandmother's wedding present in the 40s.

As a followup questions, what about the number of stitches per inch?
Will more stitches per inch make the seem stronger?

In one of my designs (a prototype using bed sheets) I may have to put a seem in the middle of the hammock somewhere, to sew two sheets together.
Will all the same theory apply there as the channel stitches?

Thanks!

[Ramblinrev]

As a followup questions, what about the number of stitches per inch?
Will more stitches per inch make the seem stronger?

In one of my designs (a prototype using bed sheets) I may have to put a seem in the middle of the hammock somewhere, to sew two sheets together.
Will all the same theory apply there as the channel stitches?

Thanks!

Shorter stitch length makes a more stable and therefore stronger stitch _to a point_. It is possible to reach a point of diminishing returns. Too short a stitch can pierce the fabric too many times. Kind of like driving too many nails into a piece of wood. This weakens the structure of the fabric. Mid range stitch length is usually a good baseline. Shorter stitches for curves. Longer stitches for speed. Very long stitches for basting. (temporary seams) Very short stitch length is useful for decorative purposes when a satin like look is desired. That is especially true for things like zig zags in button holes or around the edges of an applique. But those are not structural application.

7-9 stitches/inch or 3-4 mm length seems to be popular stitch lengths. But that is one of the mysteries which are not written in stone.

For joining panels in weight bearing applications I suggest a flat felled seam or its closely related cousin the sewn over french seam.

[Morgoroth]

Cool thanks for the reply!
I'll have to look those up.

[Morgoroth]

Last question--until I think of another one--is there a certain type of thread that works better than another?

Is plain old 100% poly thread good?

[Hiknhanger]

Last question--until I think of another one--is there a certain type of thread that works better than another?

Is plain old 100% poly thread good?

Plain polyester is fine. Just don't get the Coats & Clark junk that is everywhere. DIYGearsupply and others sell good quality thread. Gutterman is very popular among DIYers here. I bought mine at the local sewing shop per recommendation of my friend the owner. It isn't Gutterman, but is good quality. Better thread has less loose lint that flies off and cakes up the mechanism of your thread injector and is just manufactured more consistently. Ramblinrev makes a point that high strength thread is not necessary. If there is going to be a failure of a seam from overloading or something, better the thread give than the fabric. Cheaper to re-sew than have to buy more fabric.

How'd I do Ramblinrev?

[Ramblinrev]

A note about cheap thread.... Thread is only as strong as its "staple" length. The staple is the raw material used for spinning the thread. The longer the staple the stronger and smoother the thread. The longer the staple the fewer ends there are to separate and poke out of the thread twist. That makes for a better quality thread. While staple is usually associated with natural fibers, all fibers have a staple length. High quality thread uses long staple lengths to spin the twist. Cheap threads may use industrial waste to spin as it is a cheap resource.
Those staples are going to be shorter. The thread is more brittle and easier to break. It has more fuzzies to clog the machine. There fore... use the best thread you can get. 100% polyester is preferred for outdoor use since it does not rot like natural fibers are prone to do. Coats and Clark makes a variety of qualities of thread. Some seem to be sold to the big box discount stores (cheap and nasty) while others are sold to fabric stores and sewing centers. To denigrate all Coats and Clark is to do the company a disservice. But in general I think there are better threads out there. Gutterman's being one but here again I've heard of different qualities from that company.

Unfortunately I know of no labeling that will guide you to the "best" thread. So avoid the cheapo stuff. Buy from good vendors who take pride in their stock.

[Morgoroth]

Cool thanks!