Thread: To what grit should chisel backs be polished?

I use 800, 1200, 6000 then a leather strop with honing compound.

Thanks for the input. Would using 400 grit sandpaper be roughly equivalent, or higher, than using a 1000 King? It's much less hassle than all that flattening.

I think the question I really want to ask is:

Why is the King 6000 giving me a cloudy finish, rather than a mirror finish? Is this normal?

EDIT: Since that's a rather different question, I might post it in a new thread.

If your going to perform open heart surgery then 6000+, but if you want to just do good basic woodwork then 1000 is all you need.

I polish all of my chisels and planes to 8000 grit. If it's a new blade then test it with 8000 to see how much it is out, then if necessary start from 325/400 diamond, 1000, 5000, 8000. I generally try to maintain a consistent surface across the whole back.

lignum has the right idea. Don't get sucked into the false idea that polish will replace skill.
As examples:
If you really need "polish" for some reason, why not get all your chisels hard chrome plated? Or silver plated?
I suppose you could go to 24,000 grit stones but for wood work, is that really necessary?

I can put a "good" edge on a new razor blade. 4,000 grit waterstone then a green cpd on a leather strop. If I have learned any tricks, it is this: don't push too hard = go easy.

When rehabbing tools, do the backs to the same point that you do your bevels.

Wasted effort otherwise.

The cutting edge consists of the intersection of the bevel and the back. No point in finessing one while the other is left relatively coarser.

After that, in use, you can do some touch-ups of the bevel but then will have to return to the back to remove the 'wear bevel'.

I have found that using the strop and some Veritas green on the backs, after the 6000, gives the sharpness I'm after.

I think the problems with sharpness I've been having aren't anything to do with the finish, but rather the flatness. I've been using an overly course WD abrasive, and have been too impatient, so I've dubbed the edges without actually getting a nice, consistent scratch pattern along the edge. It didn't really become clear until I put it on the strop, which really polished the high spots. That means I have to redo most of the chisels using waterstones instead, which isn't a prospect I relish. Then again, learning patience is part of the exercise, and it was my fault in the first place, so I can't complain.

How long do you ordinarily spend at the initial flattening stage, on course diamond or ceramic stones? Somebody mentioned roughly 1000 strokes on another thread.

Originally Posted by snafuspyramid

How long do you ordinarily spend at the initial flattening stage, on course diamond or ceramic stones? Somebody mentioned roughly 1000 strokes on another thread.

As long as it takes, seriously and not being smart about it. Diamond stones in my experience lose their initial ability to remove a lot of material very quickly and the whole process slows down. I must admit though that they are very impressive until that point but I have thrown three out now due to this problem.

I use a Worksharp these days followed by a bit of MDF with diamond paste from McJings on it. Very impressive results on some very ordinary chisels.

Eddie, here's some DIY and other powered means for flattening backs:

https://www.woodworkforums.com/f127/b...-power-142000/