My stone grader is getting pretty uneven. Has anyone ever used the Sharp Pebble dual grit flattening stone (https://sharppebble.com/products/dual-grit-flattening-stone) to flatten it or to use it in place of the stone grader to grade the SG250?
Well, it may work OK.
This is not what you asked but just in case it is useful...
Quite a few people here use diamond coated plates of different grades to grade the stone. It has been discussed here a lot.
I bought 80 grit and 400 grit diamond plates from Aliexpress very cheaply which work well.
Something like these... (https://fr.aliexpress.com/item/33033776989.html?spm=a2g0o.productlist.main.15.268aIlzMIlzMFo&algo_pvid=47d9d9a3-3c62-4065-85ef-ce3ad0ab879b&algo_exp_id=47d9d9a3-3c62-4065-85ef-ce3ad0ab879b-14&pdp_ext_f=%7B%22order%22%3A%22122%22%2C%22eval%22%3A%221%22%2C%22fromPage%22%3A%22search%22%7D&pdp_npi=6%40dis%21EUR%215.56%210.99%21%21%216.37%211.13%21%40210385bb17671727856474855efb1e%2112000032939810444%21sea%21FR%210%21ABX%211%210%21n_tag%3A-29910%3Bd%3Abcf8f2a5%3Bm03_new_user%3A-29895%3BpisId%3A5000000187633565&curPageLogUid=ckwGyKZCjfAb&utparam-url=scene%3Asearch%7Cquery_from%3A%7Cx_object_id%3A33033776989%7C_p_origin_prod%3A)
The ones I got are rigid enough to flatten the stone as well instead of using the Tormek truing tool. You may need some adaptation (or an imaginative idea) for keeping the stone round at the same time depending on the size of the diamond plate if you want to do this.
On Youtube Vadim (RIP) of Knifegrinders shows how to use the diamond plates:
https://youtu.be/141hD1d1zj0?si=rxdJOJUAxfsF2I4d
Hope this helps!
Drilon