Tiny grooves in a cocobolo blank

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Woodchipper

Woodchipper

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They are not noticeable unless you look real close. I know they are there. I used a spindle roughing gouge to turn the two pieces, running it back and forth to keep the blank even. However, I watched three videos by Mike Peace. He mentioned square edges on tool will catch on tiny scratches and dents on a tool rest. Possibly a "hesitation" in one place? I have filed the tool rest a couple of times but still see imperfections. OK, several of my tools have square edges so it looks like a session with the grinder in the near future. Any other tips or thoughts are appreciated.đź‘Ť
 
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As a temporary fix why not bind a length of drill rod or round hss to the top of the tool rest ? Keep the tape away from the area you are floating the tool along.
 
It is possible for scratches on the tool rest to transfer to the workpiece. And tool rests do gather scratches - especially tool rests made of mild steel. They are usually caused by catches, and unless you can find a way to completely avoid catches, you will have scratches. As Ian said, a tool rest with a tool steel rod brazed across the top is far less likely to have this problem, and in fact many high-end tool rests have a piece of 'drill rod' as the working edge. Otherwise, the best advice is to periodically file the working edge smooth (this is the kind of maintenance I tend to do about once a year, perhaps on a special day like New Year's Day).

The tool that is likely to most often encounter this problem is the skew. A simple solution is to round over (ariss) the square corners of the shank; a rounded edge will ride over them with minimum transfer to the work surface.

Fortunately, most of the time the scratches that are transferred to the workpiece get sanded away and aren't visible when the piece is finished.
 
Square edges catching remedy: Skew or radiused carbide insert. I have two HSS scrapers than have been shaped and sharpened in a radiused insert shape. (I did that before I ever heard of radiused inserts.)
 
The spindle gouge has a round bottom which shouldn't create anything like that unless your rest is very rough. Might be something else.
 
The skews are my main concern. My son is an engineer and has access to the machine shop at work. Finish and polish the tool rest and get a free lunch at the local Mexican restaurant. Also, I plan on rounding the corners of my two skews and any other tools that would cause the problem. Or I could give him the tools and he gets an appetizer or dessert. Thanks to all for your help.
wouldentu2?, the spindle gouge was OK but I used a skew for the final passes, hoping to get the smooth finish. Decent but not to my liking.
 
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