If you're a veteran pin buyer, you'll know there's a grading system that artists use when pricing their pins! If you're new to the collection / making game, pin grading is pretty much quality check. Since manufacturing pins are a handmade process, there will inevitably be some with flaws. The severity and quantity of flaws is a gauge of how good (or bad) your manufacturer is. Below are some flaws you may come across:
Dents: Found on the edges of pins due to the way pins are plated.
Scratches: Can occur on the enamel fill
Blemishes: Dirt can get trapped in the enamel fill leaving blemishes
Under Enamel Fill: When not enough enamel is filled into the metal, it leaves the surface uneven and casts a minor shadow
Over Enamel Fill: When too much enamel is filled into the metal, the lines of the design separating the enamel can become noticeably thinner. When overfilled, sometimes the enamel color will bleed over to other parts of the design.
Bubbles: Sometimes small air bubbles get trapped in the enamel and air bubbles are created when the pins are 'baked' leaving little light splotches of color on the enamel.
Chipped Enamel: Enamel pins are made of metal and coated with the colors you're familiar with, i.e. gold, silver, rose gold, nickel etc. Every once in awhile its possible for the color to chip.
There are no universal rules for pin grading that you have to follow. Just be fair and put yourself in your customer's shoes... if you saw a pin with a little scratch on it, would you want to pay full price? Each artist grades on their own scale. Many have two tiers: A Grade for little to no flaws and B Grade (or often times called 'seconds') for minor flaws. However, harsher critics who break down their grading even further into three or four tiers with a C/D Grade for pins they deem are so flawed that they're only acceptable at a heavy discount (or even free). I also have C Grade tier, but fortunately I haven't come across enough to feel like I need to sell them. My C Grade tier includes:
Holes: Caused by bubbles that get trapped during the enamel fill process. After the pin has been baked the surface is polished, a hole is what's left of a bubble that was trapped in the enamel.
Missing Enamel Fill: Sometimes somehow a part of the enamels is missing a section of fill. It may have fallen out due to getting loose after baking, but not too sure!
So once you've gone through grading all your pins as best as you can, now what do you do with the flawed pins? Well in the end they are just minor flaws and some customers don't mind something that's barely noticeable! Many artists typically put these flawed pins into a 'Seconds' Sale because it sounds better than B Grade Sale or B Sale... but call it whatever you want! By running flawed pins at a discounted price, you can reach an audience who loves your work but have a budget.
How many flawed pins should you expect per batch? In my experience, my acceptable rate is 15-20%. Once it starts ticking higher, I start ringing alarms to my rep who will typically request to have the flawed quantity remade. Why do I accept such a high rate of flaws? Seconds are pretty useful when it comes to pop-up shows. I enjoy using them as prizes in a small capsule machine that catches people's attention when they walk by. I also want to give customers a chance to purchase slightly discounted pins because some just don't have the budget or may want more designs than their wallet allows. For the really big pin makers, sometimes they use B grades as a promo freebie when customers purchase more than a certain dollar amount! In the end it's all up to your discretion.
Last of all, what about those noticeably flawed pins with missing enamel fill, incorrect color fill, etc.? Fortunately I've only had less than I can count on one hand and typically I just hold onto them and pin them right onto one of my travel bags without any fear of it getting damaged... because it kind of already is!
Again how 'flawed' a pin is up to you the maker! Grade fairly and find homes for all your pins!