Steve Voigt
Bill, perhaps you can share some links or sources…I've not found al ox in the sizes mentioned here. I can get a tin of the chromium for $10 and as William said it will probably last a lifetime. Is the same true of al ox?

Assuming it is readily available, two possible issues are grading and aggressiveness. Like I said I haven't used the chromium yet, but it's reputed to be very uniform and doesn't cut aggressively. I don't know how the al ox compares on those fronts but it does cut pretty aggressively. That's undesirable for the application I proposed, but it might be desirable for others.