I have one that has the same cutting to it.
I think it is the pad backing that is doing the cutting and thought that maybe I'm running them at too high of speed, or me not keeping the pad flat like I'm edging it.
I do wish the foam was a little stiffer, but besides this one, these are awesome pads.
I'm using them with a Duetto.
https://uploads.tapatalk-cdn.com/201...a894495781.jpg
Like yours, the cutting is straight down, not from hitting something from the side.
Other pads show were used for the same detail.
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