Sharpening stone help needed

[yamato]

Hi

a stone that i have for quite a long time has developed a concave slope. is it still good? should i flatten it ( how to? ) or should i replace it.

I find that i can no longer sharpen using the entire length of the blade and i get by using parts of the stone.

is it a problem with my sharpening method that caused the stone to curve?

 

[richard j]

if you want to flatten your stone, rub it on a new flat concrete block with a small stream of running water and some liquid soap.

 

[ryan9977]

i use a dmt xxc plate to flatten my stones and also use it to thin out an edge.....i find it great for both purposes....i use waterstones so i just soak my stone and flatten on the plate.....a good way to tell if it is flat is to draw a grid of lines in pencil .....then rub the plate on top of the stone till the lines are gone.....i know alot of people use coarse sandpaper on a hard surface also......what kind of stone are you trying to flatten...ryan