Carborundum 108 Combination Sharpening Stone

[xtharosx]

Hey guys,

I am new to the forum and recently got into knife sharpening. I came across a few sharpening Carborundum combination sharpening stones in my parents' garage. I am trying to figure out which side is the coarse side and which side is the sharp side. They both feel the same to me.

One side is a dark grey that seems to sharpen fairly well. The other is a light grey that tends to form a powder all over the place when I am sharpening. This side doesn't seem to sharpen that well. Any thoughts?

Thanks in advance!

 

[spyken]

on the carborundum stones I have, light is coarser, dark is finer. but you should really be able to see and feel which is which, it's foolproof. if your stone isn't sharpening well, then maybe it's glazed up...just get scouring powder (with the abrasives) and scrub it well.

 

[xtharosx]

on the carborundum stones I have, light is coarser, dark is finer. but you should really be able to see and feel which is which, it's foolproof. if your stone isn't sharpening well, then maybe it's glazed up...just get scouring powder (with the abrasives) and scrub it well.

Spyken, thanks for the reply. Looking at the stone the dark grey side looks a lot coarser than the light grey side. The powder forming from the light grey side also leads me to believe that this side is also the fine side since it seems to be made from a softer stone. However, the dark grey gets the knife razor sharp, but when I switch to the light grey to finish the blade it gets dull again (This is for all 3 of the stones that I have). I guess it's my technique that is lacking and making the blade dull. I guess I have to practice more...

Thanks for your advice!

 

[spyken]

yes, it really depends on what carborundum stone it is...they are great for flattening waterstones so don't throw them away. I have just checked another stone, it's like yours...dark is coarse, light is finer. But I normally cannot get a shaving edge on my carborundums, they are quite rough. however they can produce a really aggressive meat cutting edge. If you don't have a strop, just use cardboard loaded with some polishing paste.

 

[HeavyHanded]

Since you have several, check them to see if they're still flat. You can rub them together under some running water to flatten them back out if they're not. Draw a grid on the stone with a pencil and see where how flat they are by checking where the marks are being ground off when rubbed against another (preferably more flat) stone. The fine side on these older stones is frequently dished out a little. With a nice lapped stone and good technique you can get a very nice edge from the fine side - more than good enough to shave arm hair. Beware, the coarse side will grind a very nice utility edge but can also raise a burr or wire edge that will feel like a wicked sharp cutter but fail almost immediately.

Use a Sharpie to see where you're grinding on the edge of your blade.

HH