Man, I’d love to hear from an abrasives engineer on these test results. Backing material, coating, abrasive type, how they all play into the performance of these flap discs.
Hey Fireball, great vids. But you know what we need. A ranking among brands with Inches from best results/dollar. Inch per dollar is useful ranking, inch per minute is also useful, inch per dollar per minute would work best. So you divide inches from best result, for the average price of the disc, and you divide that again for the time it took. Another metric would be "ease of use" and that value could be extracted based on the difference between the worst result and the best result (I mean from different tests). The wider the gap it means the disc is very specific on what it needs to be used effectively. That is not insignificant. Those of us that had to train dozens of guys to use a hand-grinder properly know. If a disc is too specific yielding terrible results unless it is used in a very specific way, that will not work with some guys, so it would be interesting to know what discs shows solid performance across the board. Now let me tell you something that would have been nice, but it would make your test too difficult: scale resistance. Most discs get completely dull if you skate them over medium to thick mill scale. Which does not make sense to me since hematite is supposed to be only 6.5 mohs hardness, thus softer than all abrasives used. However you skate your cubitron over mill scale one time and that's it, all the abrasives get that shiny head, and the disc is done cutting.
Man, I’d love to hear from an abrasives engineer on these test results. Backing material, coating, abrasive type, how they all play into the performance of these flap discs.
So with those results, it brings up a question about those turbo fan designs used on some flapper disk and the purpose for the innovation.
Hey Fireball, great vids. But you know what we need. A ranking among brands with Inches from best results/dollar. Inch per dollar is useful ranking, inch per minute is also useful, inch per dollar per minute would work best. So you divide inches from best result, for the average price of the disc, and you divide that again for the time it took.
Another metric would be "ease of use" and that value could be extracted based on the difference between the worst result and the best result (I mean from different tests). The wider the gap it means the disc is very specific on what it needs to be used effectively. That is not insignificant. Those of us that had to train dozens of guys to use a hand-grinder properly know. If a disc is too specific yielding terrible results unless it is used in a very specific way, that will not work with some guys, so it would be interesting to know what discs shows solid performance across the board.
Now let me tell you something that would have been nice, but it would make your test too difficult: scale resistance. Most discs get completely dull if you skate them over medium to thick mill scale. Which does not make sense to me since hematite is supposed to be only 6.5 mohs hardness, thus softer than all abrasives used. However you skate your cubitron over mill scale one time and that's it, all the abrasives get that shiny head, and the disc is done cutting.
its a nice colour ..