The skill of Pattern Grading involves using a master pattern and moving it according to a set of grading rules and measurments that are predetermined by industry and other bodies to increase or decrease the size but to retain the proportion of the original master pattern.
As a grader you must prepare a grading plan to allow for proportional distribution of measurements, according to the style or design of the master pattern.
This grading plan is then followed by the Pattern Grader who moves the master pattern, marking in all the grading points. All pattern movements are of 90deg to either the Centre Front, Centre Back or Straight Grain of all pattern pieces. A circular path (either clockwise or anticlockwise) is followed when marking grading points. Then finally these points are blended together to produce a pattern piece/s of the required size.
A pattern may be graded with all sizes showing on the one sheet. This is called a "Nest" and finished pattern pieces will be taken from this at a later stage. Some of the commercial patterns are sold in this manner with sizes grouped together in a nest.
Another method of grading allows for the pattern to be graded one size at a time, the new pattern piece cut out and then used to make the next size etc. This is the method that I use all the time, I find that it works the best for me.
There is also another way to grade and that is using the master pattern to make all the sizes without cutting each one out first. So you would use for example the master pattern size 10 to make 8,12, 14, 16, without cutting out the previous size always using the master pattern.
Before begining to grade it is important to check the accuracy of the pattern, the amount of pieces and the pattern markings of the master pattern.
In Australia grading is used within the clothing industry and patterns are altered by size according to Australian standard measurements, to purchase Australian standard measurements click on the following link: http://www.saiglobal.com/shop/Script/ICSDocBrowse.asp?Code=61.020&StdType=AS
This technique of grading can also be adapted to grade patterns to an individual's measurements, for example private dressmakers may use this technique or something similar to adapt a pattern to fit her customers measurements. Other industry people such as boutiques and designers may use this technique to adust patterns.
Advances in technology has over the years made grading more efficient and quicker resulting in faster production . However, it is important that the operator of the computer must have the knowledge, skills and experience in both the principles and practices of Pattern Grading.
I will be offering in the near future 17 lessons on "How to Grade". If you would like to take the lessons please email me and I will put you on a waiting list and as soon as I release the lessons I will contact you. The cost will be approximately AUS$200.00. The lessons will be by correspondence.
By the end of the lessons you will have the knowledge and skills to be able to grade any garment using the grading measurements and rules.
Contact me at firstname.lastname@example.org if you wish to take the lessons.
If you're a business and need some professional grading done then please contact me for pricing.