Scraping edge pictures

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D_W

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I busted out a scraper to compare in terms of removing finish from the panels that I showed in another thread. I thought I'd gotten all of them, but missed the back of one. One of the least figured ones and a pair that's cupped a little bit.

It might come across that I don't like scraping, but I do like scraping quite a bit. It's satisfying - it just is rarely as fast as planing, even for surface work like this and it's always the case for me that planing as well as possible still leaves less work to do with anything else that may be needed on the worst of woods (or swirling runout, etc).

I also have found a rank scraper to be easier scraping guitar tops after spoke shaving most of the material off - just the curved profile scrapers that most people probably get in a set and toss them aside.

But, not surprisingly, as easy as the scraping is to get shellac off of these panels, it's about 1/4th as fast as planing the finish off on hard maple.

That also made me think, I've never taken a picture of a scraping blade edge under my microscope, so here is the first. Instead of doing what I would normally do (relatively fine edge), I used an extra fine india and then burnished just that. I think most would consider this fine, but when you roll the burr, you can feel the edge isn't perfect. I can't think of a reason *not* to have the edge perfect as it doesn't take any more time to use the washita and then lighten the touch, but I wanted to see how much smooshing of the steel the burnisher does.

Turns out, it's quite a lot.



The tiny faint line is the rolled burr facing up toward the microscope lens. The burr curves, so that part looks like the edge is unburnished, but it's just reflecting light somewhere else, at a diagonal, and the lens and top tube camera aren't in line to see it. And then the face above the burr is shiny again.

Take my word for it, there is a lot of visual smoothing of the steel from the burnisher here.

work will be busy for me for about a month starting now, so forum time is the first to go, shop time probably cut. But I'll try to remember to come back to this.

For scale, the height of this entire picture is a little less than 2 hundredths of an inch. I think the little dark spots on the edge are the discontinuities that i can feel with the burnisher just from finishing with an india stone.

I never listened to a scraper guru that I can recall, but two things strike me as important. The edge should be polished so you can feel if there is any dirt or filth on the blade (which will distort a burr), and because if the edge is free of defects, the finish that it leaves will be very bright with no little tiny lines.
 
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