I've been meaning to write this for a while but didn't quite get around to it. Then Seamstress Erin and I discussed it at length during our fabric shopping in Chiang Mai and I still didn't write about it. And then yesterday I saw a post by someone who discovered that the finished garment measurements on her McCalls jacket pattern were completely inaccurate. Unfortunately, I now can't find this post so if you know who this is, please let me know so that I can credit the author.
I had first read this very interesting thesis a while ago but didn't pay enough attention to the details. It was written by Debra Lee McLendon at North Carolina State University as part of her Master of Science (Textiles). We'll come back to this shortly.
When I was making M6702 I was looking at finished garment measurements, one of which was Hips 142 cm or 56.5". However, 142 cm does not equal 56.5" so one of them has to be wrong. 56.5" is actually 143.5 cm, so if you were to go by the metric measure you are already 1.5 cm out. Then I measured the flat pattern and the finished garment size at the hips is actually 145 cm.
So this prompted me to go back to the thesis. Basically, the author made test garments from fitting shells (Vogue and Butterick) and semi-fitted dresses in both size 10 and size 18. The semi-fitted patterns were from Burda, Butterick (size 10 only), McCalls and New Look.
These garments were then compared to both the pattern companies' stated ease charts and finished garment measurements. This is what it found;
Do finished garment measurements in key areas printed on patterns conform to the
company ease specifications for each fit category? Generally, no.
- None of the three fitting shells met ease requirements in all three areas. The size 10 Vogue came closest to meeting the required amount in the bust, whereas both brands of the size 18 had too much ease in the bust. All three patterns had too little ease in the waist and hip.
- The only brand to meet ease specifications for the semi-fitted category of the size 10 patterns under evaluation was Butterick #5746.
- None of the brands of the size 18 patterns met the ease specifications for the semi-fitted category.
- None of the brands evaluated met their finished garment specifications when compared to the tissue measurements.
I know that you are all thinking "Well, yes, we know they have too much ease."
However, I had always thought of that in relation to what it seems most of us find acceptable. I hadn't really thought about the fact that they do not have the ease they claim to have or should have according to the companies' own specifications. It is also very easy to dismiss what seem to be small differences. After all, half an inch isn't very much. But when a fitting shell has half an inch too much ease in the bust, this is at least a 20% difference.
Do pattern companies really think that give or take 20% here or there is ok?
Now just have a quick look at the last point from the thesis above. That's right, the one that says
None of the brands evaluated met their finished garment specifications when compared to the tissue measurements.
We can argue about ease amounts, after all desirable ease and the fit it provides is subjective. But now we are talking about accuracy. As the author states, the tissue pattern measurements on all brands failed to match the finished garment specs for both the bust and hip.
That's right, not one of the patterns researched had accurate finished garment measurements.
The author concluded with this, Based on the data, it would not be possible to produce a garment from any of the patterns that matched the expected finished garment specs provided on the patterns.
How is this considered acceptable? How have we come to accept that patterns just are inaccurate?
I must admit that I fear an avalanche of "that is why you need to make a muslin" responses. But surely a muslin should be to tweak a pattern to our unique bodies not to compensate for the fact that the initial pattern is just plain wrong?
I'd love to know what you think.