# I Built a Machine that Tests Every Flap Disc **URL:** \ **Category:** Abrasives\ **Created:** [December 14, 2024, 3:07pm UTC](https://fireball.discourse.group/t/i-built-a-machine-that-tests-every-flap-disc/3027 "2024-12-14T15:07:13Z")\ **Posts on this page:** 5\ **Page:** 1
**Author:** ![Fireball\_Jason](https://yyz2.discourse-cdn.com/flex036/user_avatar/fireball.discourse.group/fireball_jason/32/52_2.png) [@Fireball\_Jason](https://fireball.discourse.group/u/Fireball_Jason)\ **Post date:** [December 14, 2024, 3:07pm UTC](https://fireball.discourse.group/t/i-built-a-machine-that-tests-every-flap-disc/3027/1 "2024-12-14T15:07:13Z")
Hey guys, As some of you know, I recently tested a bunch of grinding discs. Well I just came out with a new video you should check out here: [![](https://canada1.discourse-cdn.com/flex036/uploads/fireball/original/2X/b/be3ee17624a2eb1d2e712a8f32ef777745580213.jpeg "I Tested Grinding Discs with a Custom Machine – Who Will Survive the Ultimate Challenge? PART 1.") ](https://www.youtube.com/watch?v=RhItq6IQQJo) As an inventor, I’m always looking for ways to improve the tools I use, and my latest project was no different. A problem I’ve faced is seeing many different takes online as to which flap disc is the best; I’ve read countless reviews and seen many videos people have done, but wasn’t convinced those testing methods actually matched real-world conditions. ![Some of the discs tested in the Fireball Flap Disc experiment](https://canada1.discourse-cdn.com/flex036/uploads/fireball/original/2X/a/a8218167499eb97b9e6871ec6caf2d8c65d62418.jpeg) So I set out to finally answer the question “which flap disc actually is the best?” and build a custom test rig for grinding discs, one that could test their performance, durability, and efficiency under these real-world conditions. The goal wasn’t just to run tests, but to create a rig that would provide reliable, consistent results to help me figure out which discs actually perform the best and under which conditions. ![The full test rig in action for testing every single grinding disc](https://canada1.discourse-cdn.com/flex036/uploads/fireball/original/2X/7/7b93f26b4bc6c8c20d10d849c3d4313a27b27f94.jpeg) The first step was designing a rig that could handle different variables like weight, angle, and pressure. I decided on a setup with two grinders, each mounted on adjustable platforms. This setup would let me control how the discs were tested and make precise modifications, like if the disc was shaped in a way that needed to be placed at an angle. ![I had to invent a way to manually set the grinder at a selected angle](https://canada1.discourse-cdn.com/flex036/uploads/fireball/original/2X/e/e0e0e3ab01d97f033e7373ef0972617f58f9a7a6.jpeg) One of the key features of the rig is the oscillation system I built. This system moves the test platform back and forth, mimicking the actual grinding motion you’d see in a real workshop. (You can see how I used the Monster squares and fixture table to align the rails in the image below) To track how much material was being removed, I added measurement markings to the test bars, so I could see exactly how much was ground off during each test. ![Using the Monster Square and Dragon Wagon helped me fixture and weld these parts incredibly fast](https://canada1.discourse-cdn.com/flex036/uploads/fireball/original/2X/9/9184ddfb8a1f67e0615338b26f1f4807b59cd207.jpeg) ![The oscillating base with the motor mounted to it](https://canada1.discourse-cdn.com/flex036/uploads/fireball/original/2X/6/68313dac9e2da1ead9133bd015df85010d8efb84.jpeg) ![I added hash marks to the test coupons to make data collection easier](https://canada1.discourse-cdn.com/flex036/uploads/fireball/original/2X/6/617511cd0de84770c03144d888a3bda6738f3a99.jpeg) The test setup included multiple cameras, positioned to capture everything from the contact point between the disc and the test bar to the amperage being drawn by the grinders. But managing the sparks created by the grinders was another challenge. Originally I didn’t have any guard on, and it made it very difficult to see what was going on in the captured footage due to the sparks flying everywhere. So I designed spark diverters to direct the sparks away from the test area. Keeping everything safe and visible while the tests run was also key to getting reliable data. ![Overview of the testing setup to find the best grinding disc ever made](https://canada1.discourse-cdn.com/flex036/uploads/fireball/original/2X/c/c39139169ae90fd11b13b077e36a4108691ae9d6.jpeg) ![Custom spark diverters made for the grinders](https://canada1.discourse-cdn.com/flex036/uploads/fireball/original/2X/2/2f1193b46eca234804dbc631fac2f9be4811c749.jpeg) _BEFORE_ ![BEFORE spark diverter addition](https://canada1.discourse-cdn.com/flex036/uploads/fireball/original/2X/4/4ad4273ee398053053ed19a9c51fb2c3e9801d74.jpeg) _AFTER_ ![AFTER spark diverter addition](https://canada1.discourse-cdn.com/flex036/uploads/fireball/original/2X/e/e855d406162ac43b8a6dc13029851fb57d8a35cb.jpeg) The data that was captured measured multiple variables: 4 & 8 pounds of pressure, and room temperature steel and hot “freshly welded” steel. It wasn’t until after 134 tests were conducted, that I realized we needed another variable: slower disc speed. The problem was some of the high end discs weren’t performing well, so I figured turning the disc speed down would set them up to give better results. So I tested every single disc again with a slower speed, but only at the 4 pound pressure. ![A single disc originally underwent four tests until I added variable speed to this experiment](https://canada1.discourse-cdn.com/flex036/uploads/fireball/original/2X/4/43a654ad6bd46c6cd32cf87e84c03476f15899b0.jpeg) ![This is the variable speed grinder I added](https://canada1.discourse-cdn.com/flex036/uploads/fireball/original/2X/5/5c4abbf7120c1c22e946c0c132d02e4200372866.jpeg) The results are being analyzed, and I’ll be posting all the data here on the Fireball forum. If you’re curious about how these flap discs performed, be sure to check back here! Ultimately, this was a lot of work, but it was also a great dive in shop science and data collection. Let me know what you think. Jason ---
**Author:** ![larry0196](https://yyz2.discourse-cdn.com/flex036/user_avatar/fireball.discourse.group/larry0196/32/522_2.png) [@larry0196](https://fireball.discourse.group/u/larry0196)\ **Post date:** [December 14, 2024, 3:14pm UTC](https://fireball.discourse.group/t/i-built-a-machine-that-tests-every-flap-disc/3027/2 "2024-12-14T15:14:03Z")
Great video Jason, I watched the video on Youtube and find your tests interesting. In a unrelated thought when you were said you were collecting data. If you have your members add their YT account to their FireBall forum profile you could see who, what, where, and why of your video views and know if you customers are watching your website or YT more, where they are coming from in search, see interaction time, and comments left. ---
**Author:** ![ADAM\_Poston](https://yyz2.discourse-cdn.com/flex036/user_avatar/fireball.discourse.group/adam_poston/32/2451_2.png) [@ADAM\_Poston](https://fireball.discourse.group/u/ADAM_Poston)\ **Post date:** [December 15, 2024, 2:39am UTC](https://fireball.discourse.group/t/i-built-a-machine-that-tests-every-flap-disc/3027/3 "2024-12-15T02:39:40Z")
Enjoyed the video but find myself constantly checking for updates of when the first results video comes out in the forms. I think your design, testing methods and data collection should reveal some vaule add when purchasing these products. Just spent a little extra on upgraded flap disc yesterday, very interested to see how they stack up to the competition. ---
**Author:** ![Siemen](https://yyz2.discourse-cdn.com/flex036/user_avatar/fireball.discourse.group/siemen/32/2701_2.png) [@Siemen](https://fireball.discourse.group/u/Siemen)\ **Post date:** [December 15, 2024, 12:23pm UTC](https://fireball.discourse.group/t/i-built-a-machine-that-tests-every-flap-disc/3027/4 "2024-12-15T12:23:16Z")
Great testing setup! Super curious for the results and conclusions. Crazy amount of work. ---
**Author:** ![Jeff\_Brymer-Bashore](https://yyz2.discourse-cdn.com/flex036/user_avatar/fireball.discourse.group/jeff_brymer-bashore/32/3013_2.png) [@Jeff\_Brymer-Bashore](https://fireball.discourse.group/u/Jeff_Brymer-Bashore)\ **Post date:** [December 29, 2024, 1:19pm UTC](https://fireball.discourse.group/t/i-built-a-machine-that-tests-every-flap-disc/3027/5 "2024-12-29T13:19:32Z")
Hi Jason, Are you able to post the raw data to the forum in a CSV file format? Or excel file? Or a google sheet? Thanks!