This is a set of anti popcorn funnels and "spinners" for the DF83, originally designed to restrict the rate that beans enter the grind chamber. The design has 2 parts: funnels that operate as an anti-popcorn device. There are 2 funnels, the Anti Popcorn Insert, and the "Low Fines" version that more aggressively limits the rate that rate that beans can enter the grind chamber. a spinner that mounts on the burr carrier bolt and agitates the beans to keep them flowing into the grind chamber. The cup shaped portion slides over the top of the bolt and shaft at the center of the bottom burr, and with some wiggling, will slide down and settle snugly around the bolt head. The large disc then covers up the hole that the beans fall into and eliminates any beans from popping up out of the funnel. The spinner is optional for the normal funnel, but required for the low fines funnel in order to adequately restrict the rate that beans enter the grind chamber. In addition, I've heard that some DF83 users have a funnel shaped bellows that prevents the use of a funnel. I've designed an extra large mushroom shaped spinner which I'm calling the "Shroom", this is meant to operate standalone along with a bellows, and covers up the grind chamber opening very thoroughly, keeping any beans from popping out. Because it spins with the burr, it throws off any beans that rest on it, ensuring that they fall into the grind chamber. Based on some timings I made of grinding beans, if I pour all 15.5g of beans into the stock grind chamber and start the grinder, it finishes grinding in about 7-8 seconds and I get an extraction time of 32s. With the normal funnel and the spinner, the grind time seems to be about 8s from when I start pouring beans into the chamber and when it finishes. The extraction time is down to about 25s, indicating that there are fewer fines. I get the same timings using the Shroom and no funnel, pouring the beans into the open bellows. The resulting shot has a bump in clarity - though I haven't tried re-adjusting the grind settings to return to a 30s extraction. If I use the low fines funnel and the spinner, grind time goes to around 30s. Sometimes the last few beans linger around and have trouble falling through - if so, rotate the funnel so that the notch is on the bottom and wiggle it a little bit - the last beans will fall through quickly enough. The extraction time on the low fines setup drops to around 8s or so, and it sort of gushers out like a turboshot. This setup should work well for pourover, or if you adjust the grind settings and/or lower the extraction pressure, should give a very high clarity espresso shot (if that's your thing) by sychan. Important Notes: When mounting the spinner, wiggle it while pushing down to make sure it is mounted all the way. If it isn't pressed down all the way then the wider base of the spinner will prevent beans from passing through into the grinder chamber. Make sure you use a reasonably food safe filament for printing these designs. I personally use clear PETG which is basically what clear soda bottles are made of. Expanding your options for grinding perfection with DF83 Anti Popcorn Funnel. This advanced design utilizes 2 parts - funnels and spinners - to bring out the best in your beans. Deny those pesky airs, and keep beans flowing smoothly into the grind chamber with the anti-popcorn funnels. These handy funnels come in 2 versions - the Anti Popcorn Insert, and the "Low Fines" version that aggressively controls the rate of bean entry. The spinner, on the other hand, agitates the beans and works with the burr to make sure that every bean is accounted for. The spinner is optional for the normal funnel, but a must-have for the low fines funnel to guarantee adequate restriction of bean entry. And for those using a different bellows shaped funnel, the specially designed "Shroom" spinner is perfect for use with the bellows. But the DF83 Anti Popcorn Funnel doesn't just ensure a precise and smooth