I just picked up an stanley no3. I am trying to flatter the back of the blade and it is going slow.
Here you can see the high spot in the middle if that was a hollow it would of been a easy job.
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how should I go about getting this thing flat? Is there a short cut or is ti just going to be a long time at the diamond stone.
I have a coarse diamond stone, 1000 and 8000 shapton stones.