Sunday, March 11, 2018

The "Bag" Part of the Hedeby Bag--Construction

Bag pattern
Over the last few days, I have been thinking about cutting my fabric for the wooden-framed Hedeby bag, and how the bag should go together.

A lot of the people who have made such bags simply cut a piece of fabric for the body of the bag that is twice as long as the intended depth of the bag, fold the piece in half, and then sew up the piece on both sides.  This type of construction has the advantage of not requiring any seam along the bottom of the bag, making the resulting bag stronger.

The downside of this construction is that the amount such a bag can contain is very limited relative to its depth.  It would be fairly simple to give the bag additional volume without making it deeper by adding bottom gores (thus making the bottom of the bag much wider), but doing so would create structural weakness by adding seams in areas that need to be weight-bearing. 

Outer layer with gores pinned in.
The Sami bag Kristine Risberg talks about in her post uses a somewhat different approach to increase volume.  It appears to have a circular or oval piece set in along the bottom of the bag.  This way, there is no bottom seam, just a seam that runs along the bottom edge of the bag, all around the sides at the bottom of the bag.    For a small bag that is unlikely to need to hold much, this much labor struck me as excessive for some reason.  And it also adds potential structural weakness.  Now, instead of having one piece of fabric for sides and bottom, there are three pieces; one for each side and one for the bottom.  That still seemed to create weakness.  On the other hand, the gores in the sides approach, though still involving three pieces, allows one large piece to be used for the wider sides and bottom, preserving much of the strength advantage of the fold-over design.

Then I started thinking about ways to add side gores.  The most attractive possibility that occurred to me was to add gores on the side that are narrow isosceles triangles.  This gives width to the bag without surrendering the strength and integrity of the folded bottom.  Though I'm no graphic artist, it is easier to explain what I mean with a diagram (see the graphic to the right of this post).  I've also included a photograph showing the gores pinned where they will be sewn.  Poor quality though it is, the photo gives a better idea of the finished bag's shape than the pattern sketch.

Under this plan, the lining will feature the same shapes as the exterior felt fabric, but since linen frays while felt does not, the lining pieces will have to be cut a bit larger than the main bag pieces--enough to allow for flat-felled seams.  That is desirable because linen, unlike wool felt, does fray, and the lining will suffer closer contact with the contents of the bag than the outer bag will.

I really like the bag shape the side-gore setup provides, so I'm going to use it.  After sewing the out and inner bags together, I will turn the outer bag right-side out, and stitch the frames to the bag using the tabs.  Once that is done I will insert the sewn linen lining (which will be a second bag, in effect), turn the top edge of the lining over, and whipstitch the lining and bag together along the top edge all around.    I have not yet decided whether I will apply the amber wool strip before, or after, stitching the frames on.  If I do so afterward, the top edge of the amber strip will lie against the bottom edge of the wool tabs holding the frame in place.

This approach will be different than that used on any of the bags I've seen pictured on line.  I'm excited to find out how (or whether) it will work.  

2 comments:

  1. I think your approach will work. It's logical and well thought out, and it's going to be really cool to see how it all comes together!

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    Replies
    1. Thanks! I've already cut the pieces for the outer bag--including the tabs. Progress!

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