Author Topic: Sharpening scrapers  (Read 2384 times)

kaintuck

  • Guest
Sharpening scrapers
« on: March 20, 2015, 01:30:34 PM »
Ok fellas, I see how to sharpen a straight scraper...a diamond plate, then "burnish the edge".....
But how do those of you who use a shaper that's curved, sharpen or refresh its edges????

I got a complete set from Lee Valley......but some aren't smooth as they need to be....cause when stamped, it left minute irregularities in the areas of the edge, making small grooves when scraping the wood.......and I'm trying to get completely away from sand paper!

Marc n tomtom

Offline JDK

  • Hero Member
  • *****
  • Posts: 692
Re: Sharpening scrapers
« Reply #1 on: March 20, 2015, 03:07:13 PM »
Marc,

Just use a mill or similar single cut file held 90 degrees to the face to smooth the edge.  On a curved scraper just go lightly with a crossing motion so you don't put facets on it.

If you want it to cut aggressively then use the burnisher to roll the edge to form the "hook" by holding the burnisher at a right angle to the face and tilt the handle up a few degrees and push the steel across the filed edge.  I only do this when I want the scrapper to remove wood in the shaping phase.

I find the hook too aggressive for final finish work and just file and burnish lightly by running the steel lengthwise down the edge lightly, leaving the edge 90 degrees to the face and using that to just "shave" the wood of any hairy raised grain.

Curved, straight doesn't matter.  Enjoy, J.D.
J.D. Kerstetter

Offline Long John

  • Hero Member
  • *****
  • Posts: 1618
  • Give me Liberty or give me Death
Re: Sharpening scrapers
« Reply #2 on: March 20, 2015, 05:49:33 PM »
I think I agree with JD.

For shaping work I draw file the edge, holding a single-cut file with handle to the right I push the file along the edge perfectly perpendicular to the scraper face until I have a nice smooth square edge.  Then I burnish the edge with a hard steel rod held about 2 degrees off perpendicular to roll the edge.  The 2 degrees (or there abouts) is critical.  It ain't a lot!  If the burnisher is at too great an angle the scraper won't cut well.  The cutting is done by the tiny burr on the scraper edge.  that burn wears and bends fairly quickly so re-sharpening is done frequently.

If I want a finished surface then I will file the edge and then smooth the edge on a fine diamond plate or water stone.  The roll a burr on the edge.  this gives a far smoother surface but is more work.  The fine burr wears just as fast so re-sharpening is done every few minutes.

Best Regards,

John Cholin