Thread: Anything possible with a 300mm (11.8 inch) Wheel?

I would shoot for 60-ish or a hair less with O1

Thanks a lot Spazola (Charlie) and the rest of the guys.

I'll get down to it and see what I can turn out.

One last question for now, if I may?

What belt grades and speeds should I go for initially.

I have:

60 Grit - Roughing out/shaping - with that big 12 inch wheel I have?
100 Grit - further Roughing?
240 Grit - Post heat treatment - finish grinding (900 RPM)?
400 Grit - polishing?
and a few Cork belts - presumably for final polishing?

Small wheel attachment for shaping the tang etc = Slower speeds so as not to overheat bearings?

My sander speed control displays in Hz and it looks like 1Hz = 60 RPM

Originally Posted by spazola

I would shoot for 60-ish or a hair less with O1

After HT I use about 900 SFM at the cutting edge

the Bohler O1 is good steel mate stick with the temps etc on the sticker and will work well with Canola oil as the quench medium if you don't have anything else
you can leave the edge at about 1mm on the O1 and it hold up fine
do a couple of thermal cycles post grinding then 2 to 3 quenches at 800°c in warm (60°c ) oil, due to the thinness of steel razors only needs to get to temp and soak for like a minute or 2 each time then temper at 200°c for 1 hour & good to go

I go to 240 grit on the hollows for the my blades & take the tang & spine etc to 1000 grit preheat treat then only need a clean up of the flats & work the hollows to desired finish

I also have a 800 grit cork belt which gives a nice satin finish used with WD40 on the belt

the 11.5" will do you well for the 7/8" plus blades with the 3.5" for smaller & hollows

I recently got a 36" radius platen to play with when I next do some grinding for a full wedge finish hopefully

Wow, thanks Substance,

Looks like you are just over the ditch from me (I'm a Pom in Auckland :-)

When you write 'thermal cycles' what's done here exactly?

Seems like I'll need a Kiln soon too :-)

Originally Posted by Substance

the Bohler O1 is good steel mate stick with the temps etc on the sticker and will work well with Canola oil as the quench medium if you don't have anything else
you can leave the edge at about 1mm on the O1 and it hold up fine
do a couple of thermal cycles post grinding then 2 to 3 quenches at 800°c in warm (60°c ) oil, due to the thinness of steel razors only needs to get to temp and soak for like a minute or 2 each time then temper at 200°c for 1 hour & good to go

I go to 240 grit on the hollows for the my blades & take the tang & spine etc to 1000 grit preheat treat then only need a clean up of the flats & work the hollows to desired finish

I also have a 800 grit cork belt which gives a nice satin finish used with WD40 on the belt

the 11.5" will do you well for the 7/8" plus blades with the 3.5" for smaller & hollows

I recently got a 36" radius platen to play with when I next do some grinding for a full wedge finish hopefully

I use an 8" wheel only for doing a primary hollowing on forge blanks. That could also be a 10 or 11 " wheel.
And most of my work is done on the 4" wheel. 3.5" is close enough. I think 72" and variable speed are most important and you have those so you're all set!