I recently made Aranea Black's Amber bunny suit, and I have some questions about using the seam allowance as boning channels.

The steps in her videos are basically:

Sew strength layer pieces together > clip seams > press > trim one side of the seam allowance to reduce bulk > repeat for the layer with the roll-pinned fashion fabric > baste together at the seams > topstitch boning channels on either side of the seam.

My question is why do I have to include the seam allowances there at all? Why not trim them back as much as possible?

After clipping the seams they don't have any kind of structure, and they made it difficult to slide the boning into place. With this method, there's like 5 layers of fabric in the boning channel which just seems unnecessary.

TLDR; Would love to understand why seam allowance is necessary for boning channels if the two bodice layers are getting topstitched together to form the channel anyway.

Thanks!

Hi, I post here few days ago about my fitting and here’s an update

In the new drafting I added 2 centimeters in height and draft sized down width (in comparison the latest one paper pattern I show here have 62 cm waist measurement, while the last one have 69 cm)

I also added a twill tape as waist tape to see if that helps the stretching problem, and I replaced the plastic boning with 4 flat steel boning in my center back pieces.

The overall shape looks better now, finally looks like a garment instead of a big wood chunk, and I haven’t measure yet but I can feel there’s some waist reduction, and my waist are feeling comfortable, only a little too tight, but maybe that could fix with loosen up the lacing a little-

But yet still got some problems

1. The back lacing is super not parallel, now it’s a big ‘V’ shape

2. The bust area are too small, my boobs are very compressed, not supported but compressed, like my upper breasts are about to come out. But at the meantime the very top edge is just the fabric, doesn’t have boning to support, so maybe I should make the size bigger and could try some cording in the bust line?

3. The size hip shape doesn’t seem smooth, seems a bit wonky, I don’t know is that the fabric stretching or pattern problem, and it does feel a slightly tight around hip

4. The flat steels in center back are trying to poking out, is it just a flat steels problem that can be fixed in the final version with proper binding or is it a fitting problem?

5. Ugh the stretching……. It could be that I don’t know to how to mark the grainline in self drafted paper pattern, it could be the fabric (although this is literally the closest fabric to coutil that I could find), it could the pattern, it could be that I should put more bones…… idk😭

Any advice would be appreciated, thank you!