Tuesday, August 20, 2013

BC1 - POLISHING


POLISHING

Polishing is one of those time consuming tasks where patience pays off.  The process is to start with some 150 grit sand paper work the surface evenly until no scratches are visible. Then move up to 220, then to 320, then 400 and so on, each finer grit is taking out the previous grit's scratches.



Sandpaper sheets are cheap and effective abrasives for polishing a knife. I buy the bulk packs of commonly used sizes ranging from 80 grit to 600 grit. I cut the sheets into 6 pieces like shown. I then have a suitably sized block of wood to hold the paper flat while sanding.


It's not uncommon to use a whole sheet on a blade. You'll feel when the sandpaper stops "cutting"  or "dragging" like a new piece. Toss it out and grab another piece. A squirt bottle with water comes in handy as does a rag so you can check your work.


All of the sand papers use water to remove the debris and keep the metal surface cool. I clamp the blade to the bench and work longways over the blade, adding water periodically.

Note that I am not overly concerned with polishing the area that will be hidden by the handle slabs.



It's still not complete at 600 grit, but the satin finish looks pretty good and there are no noticeable scratches or scars.


Once we make it to 600 grit, we can start with the polishing compounds on the polishing wheel.



Although it sounds like an oxymoron, black rouge is an abrasive with emory particles. It is for course polishing. Follow this with either red rouge or green rouge for stainless steel. Since 154CM is considered a stainless steel, I will move to the green rouge on the buffing wheel.

Word is that Mother's Mag & Aluminum Polish works really well on stainless. I may try some and report back.



Before I get to the final buffing, I want to shape the cutting edge bevel. I used a Gatco honing system, which seems to be hit or miss as far as holding a good angle. It is supposed to hold the angle of the stones consistent, but there is sufficient play in the plastic to cause the stone to rock a degree or two. I may have to develop a proper, sturdy jig for this


I am going to test the etching process today. I will do it on the tang under the handles. I placed a scale on and marked with a pencil to tell me where the handle will start. Then I taped the blade end off on the pencil line.

Next is the mask and etching test.

UPDATE: The knife fell straight, tip down on to the concrete floor in my garage suffering a chip on the tip. I will have to re-grind to get it into shape. Much more work than expected. 

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