A common question I find in my inbox is “how to I alter the size of a pattern?”. If you’ve read this blog for any length of time I’m sure you’ve seen me discuss the idea of pattern grading. But what is pattern grading, if you’ve never run across it before (or maybe you have and it’s still just a somewhat confusing concept)? Grading is a method of sizing a pattern up or down in size. This can be done manually using paper and rulers, or is now often done on computer programs (most often by the larger companies, since these systems can be pricy for the home sewist). Because you aren’t tied to the size on an envelope, this is an especially useful skill to have if you work with vintage patterns. But it’s a good tool to have in your sewer’s bag of tricks period, as it has many uses.

Throughout this series I’ll be going over both common and basic grading techniques, as well as breaking down how to grade some more complicated styles. We’ll be using the old fashioned, paper method, since that is most available to everyone. It is my hope that this series will be a clear overview of basic grading to get you started. I’d like to be upfront and say that this is not going to be hugely comprehensive (there are textbooks for that), nor do I know every grading technique. I have been grading using this method for the past 10 years, and have picked up some tips through study and developed my own ways of approaching it. But I feel that for the home sewist, this is perhaps the easiest method to grasp.

Please note this is not a sew along—it’s just a series. You do not have to follow along as I post these (though you are welcome to!), but can refer to them in the future when needed. These posts are rather spread out because they are time intensive to put together, and I want to give myself enough time to give them some polish and cover as comprehensively as I can (within reason) the topic.

• Paper – I use exam table paper, since it’s both transparent and cheap. This is the most important part of grading: having transparent paper. Because you’ll be tracing your original pattern, it makes life a lot easier. Another option is to use a non-fusible, lightweight interfacing (such as the gridded interfacing sold at JoAnns). Or you could use Swedish Tracing Paper. Though because of the cost I don’t recommend that for the actual grading, but perhaps tracing your final, master pattern on to. The bonus of using this is you can also pin it together to create a sort of fitting muslin (though it does not drape quite like fabric). In a pinch, large sheets of tracing paper can be used. From personal experience: don’t try tissue paper, it will only end in tears.
• Rulers – A variety of rulers and measuring tools is always handy for grading patterns. I generally rely on my gridded ruler (2” wide by 18” long with markings every 1/8”–commonly found in the quilting section of fabric stores) for the actual grading. A ruler that goes into even smaller increments (1/16”) would be handy too. I also keep a hip curve and yardstick on hand for tracing patterns.
• Pens, Pencils, Markers – Fairly self-explanatory. Sometimes I find having fine-tip markers in a few colors useful when differentiating between grading lines.
• Scotch Tape – A must for adding extra paper underneath when grading up, or overlapping when grading down. You’ll go through a lot of this, so be prepared! (I like clear tape only because you can see through it. You can use opaque tape, but it’s a personal preference.)
• Cutting Surface – I use my trusty cardboard cutting mat, but a self-healing mat will also work. I tend to pin the pieces I cut apart into my cutting surface in order to keep them from wandering/moving. So this isn’t a must, but makes it easier.
• Pins – Just regular, straight pins (as I referenced above, I pin the pieces into my cardboard mat).
• Your Measurements – Having a sense of what size category you fall into is very useful when grading for yourself. (Admittedly, I tend to “cheat” on this and just grade to the pattern size that I know I fit into, and then make my personal fitting alterations. Generally I’ll be assuming you are doing the same for the majority of the series, until I get into uneven grading in the July 6 post.)

I want to note here that while grading is a wonderful, highly useful skill, it does not take away for the need to further fit your pattern to your own body or making a muslin for some more complicated designs. As with anything that involves alteration, I always recommend double checking the fit before cutting into your garment fabric.

That sums up the supply list and next we’ll be moving on to actual grading! I plan on not only showing you through photographs, but a series of illustrations as well. Grading up a pattern size is perhaps the most common request I receive, so that will be first (with grading down following shortly behind—it’s a very similar technique though!). My hope is that by sharing this technique with you, it’ll open a whole new world of sewing skills and possibilities!

June 6, 2012 · 49 lovely thoughts
posted in sewing · tags: pattern grading, sewing workshop, tutorial