Lay flat or flat-felled seams for pyramid tents
My ultralight tents that are a pyramid or tip design have many adjoining tall triangular panels. I join my tent panels with a simple version of ‘lay flat’ seams. They have features that make the seam construction easier and the tent seams strong, stable and versatile for attaching lightweight guy attachment tabs.
My Mum (who was a skilled professional seamstress) taught me this sewing method which; is simple, does not require a second cutting. “I never knew otherwise until I did a google search”.
The seam is started by wrapping and pining the edge of the next panel to be added to the tent canopy within a ‘sandwich’ of the edge of the fabric of the previous panel that has already been joined to the canopy. “When pinned it is the best time to have a good ‘stand back’ examination the joint before committing to sewing because, in my experience, unpicking takes a lot longer than sewing!”
The first line of stitches is sewn as shown in the photo below. This method is good for a mug sewer like me. However, I was surprised that this method is at odds with all the methods that I have seen described on Youtube eg flat felled seam.
The next line of stitching sews the seam down flat and covers the last remaining raw edge.
Correct seam naming. Even when I thought I had the correct name for my lay flat or flat felled seam I was in for another surprise. The true flat felled seam is done with a machine with two needles and the machine rolls and sews both lines of stitching passing through from the top to the underside of the seam. “That’s not what my little machine can do.” The seam that I do is more correctly named a Mock Felled Seam. It even has an ISO 4916 2.04.06 number. This number comes from this wonderful link that describes in detail most seams that seemingly one could dream up or have nightmares about.
Lay flat seams with one bias cut edge
When making my pyramid or tipi tents, they have many adjoining tall triangular panels. These are specifically designed to have straight grain on one side and the bias grain on the other. The panels are arranged this way so that each radial seam is a composite of panels with a straight and bias grain.
This makes the ‘cut’ a little less efficient and the project may seem a bit more complex. However, it means that the seam stretch is both limited and even for all seams. Consequently, no seam needs to have stretch limiting tape applied. The one resulting unsupported bias edge, that eventuates at the doorway, has the webbing of the full-length door zipper to limit stretching.
“I construct my tents like a giant cape, simply adding each extra panel by its; bias grain edge to the only available straight grain edge on the steadily growing canopy. During the first critical line of stitching, there is no clutter of fabric under the bridge of the sewing machine (As in step 1.). Then for the second line of stitches, only the newly added panel needs to pass under the bridge(As in step 2.). “When I sort out my system, the complex becomes simple, but it is still tedious. My first tent (The 12 sided orange one) had 60m*2 of such stitching!”
It is also interesting to think that symmetrical pyramid tens such as mine, only have one pattern shape for all panels. It just needs to be flipped over from ‘A’ to ‘B’ sides to mark out for cutting.
[Photo of tent seam with ripstop revealing the bias component]
Summing up
The lay flat or mock flat felled seam for straight/bias seams for tents according to my Mums method has the following features:
- No cutting of bias grain fabric after the first line of stitching
- Makes bias seaming easier,
- Makes every seam have a double width of straight grain in it for good strength,
- Makes all seams have a uniform and limited stretch,
- Makes an excellent place to connect small tent guy tabs,
- Conceals and hold all cut edges that may tend to fray.
Tim
