This post is about PN numbers -another layer of complexity in pattern room management and I hope I can explain this well. PN stands for Piece Number so when we say PN numbers -and we usually do- we’re being redundant. Regardless, that’s what we call them. PN numbers are unique numbers that are assigned to individual pattern pieces. No two differing pieces can have the same PN number. We use PN numbers to manage block patterns which permits piece interchangeability between styles. You could consider PN numbers as parts numbers to distinguish pieces that are interchangeable between several (or many) different styles.
Regarding interchangeability; as you know, any given style has any number of differing pattern pieces. The pattern pieces for style 2117 were detailed in a cutter’s must and the pieces for style 21201 were illustrated in a cutter’s must pt 2. In the post What is Kaizen, I explained how the block system -style 21117- was the parent of styles 21201, 22712, 21234, 22540 and 22808. In the post How blocks work, I diagrammed how the linings of the parent pattern fit into all of those styles. With me so far?
Off to the left, you can see another diagram of how blocks work (download and print a copy here 387kb). For example, you’ll see that the pockets, lower side fronts, sleeve portions are all shared in common, with styles 21117 and 21201 branching off to be listed underneath each other. Now, if you look at the front yoke, you’ll notice the 21201 is listed off to the right of 21117. This means that the yoke belonging to 21201 is a child of the yoke of 21117 and was made from it but these pieces are not interchangeable.
Now, back to PN numbers. Below you’ll see the cutter’s musts for 21117 and 21201 sans the sketches (you can download and print a copy from here -703kb). You’ll notice that 21201 uses many of the same pieces from the parent style 21117. In addition, 21201 has PN numbers for pieces that are unique to it.
Now, to the right, I’m going to diagram the PN numbers along with the styles.
Hopefully you can see how all these pieces feed into each other (download a copy here 480kb). Now what this means -other than adding another layer of complexity- is money. Lots of money. If you can recycle pattern pieces from one style into another in an organized fashion, you can save lots of time, trouble and money.
Now, tracking PN numbers is pretty simple and you must do 2 things.
1. You’ll need a notebook with sheets of paper with columns. In the far left column, list PN numbers incrementally. Next to that -on the same line- write the piece name. Next to that you can write the style number of the parent pattern. That is just in case you can’t find this particular pattern piece when you’re looking for it and need to find it. It may be hung with the original parent pattern.
2. The next way to track PN numbers is by writing the style numbers of all the affected styles on the pattern piece itself. Here is an under collar pattern piece as a sample of that.
You’ll see that this under collar is used on 37 different styles. In fact, this undercollar is used so frequently that its PN number is not even recorded on the piece, only the affected styles using it are shown. How much time and money do you think this little trick has saved? In fact, once you have a library of interchangeable styles, it is entirely possible to “create” new styles entirely comprised of recombining existing pattern pieces in new combinations. This is the beauty of using a pattern block system. Using PN numbers will allow you to manage this interchangeability.
Now I want to make two additional but unrelated comments here.
1. You’ll note that some of the style numbers are written in green. You should know what that convention means by now. Make a practice of following standard practices. If you don’t, you need the book.
2. (beating a dead horse now) If you’re one of those people who still persist in naming your styles, how will you ever fit writing in all of those names? Again, you need to read the book. Can you begin to understand just how much of a problem this is for the pattern maker and production people? If this hasn’t convinced you, then please read this. Using names or letters is a pain in the butt for the rest of us. Pick your battles, this is not one of them. Sometimes, conformity is good.
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