Older Sandvik scraper. Can't raise a burr

[EricU]

I was having trouble raising a burr on any of my scrapers so I got a Union Accu-burr.  It works great on all of my scrapers other than the sandvik.  Now I'm wondering if they understood the assignment, it must be hardened. There are so many posts about how to raise a burr that any info about this scraper is lost in the noise.  Anyone have a scraper like that?

[AHill]

Please describe your method for turning a burr. That will help us diagnose your problem.

Unless you say something different, it could very well be you've exhausted the number of burrs you can turn. I recommend re-establishing a flat edge by sanding and polishing the edge before re-attempting to turn a burr. You really don't want a hardened edge. Scrapers are hardened to about the same hardness as a saw blade (like 50 Rockwell C max - many are as low as 40 Rc). Too hard an edge, and you either can't turn a burr, or it will break off too easily.

[EricU]

I used a 1200 diamond stone on all three sides to a pretty good finish. Then I used the accu-burr as instructed. Maybe I should take it to the 200 grit stone and get rid of some of the edge.  Not sure it's really worth it, I have plenty of scrapers and the accu-burr works great on all of them other than the Sandvik. But I'm the kind of person that doesn't give up on tasks just because they are impossible.

[AHill]

Eric, I think what might help is to use a file to joint the edge first, then use your stones to polish the edge before trying to turn a burr again. Repeated burnishing to turn a burr could have caused the steel near the edge to harden, which would make it more difficult to turn a burr. Filing gets rid of the work-hardened steel near the edge and gets you back to a softer steel that will be easier to turn a burr.

[Pedder]

I don't now about this Sandvik scraper, but In Germany you can buy some Lackziehklinge, wich means varnish or laque scraper.
These are hardened. https://www.farbenexperte24.de/zubehoer/...ziehklinge

they are not supposed to us with a burr, but just a sharp 90° edge. Take only tiny shavings from varnish.
(drops, dripmarks German term is Laufnase, running nose, wich describes the picture well.)

Edit: https://www.tonet.ch/images/Katalog/2022...seiten.pdf oage 29, offers Sandvik Lackziehklinge 474

Best regards
Pedder

[EricU]

That's really interesting, it's a Sandvik 475.  When I googled that, I found this at Highland woodworking:

"The Sandvik Scraper" is the original card scraper that's long been famous in woodworking circles. After Sandvik and Bahco merged in 1991, the Bahco 474 became the scraper that replaced the 475 Sandvik Scraper that's referenced in Tage Frid's Book 2: Shaping, Veneering and Finishing.

Bahco's hard Swedish cold-rolled, hardened and tempered chrome-nickel steel takes a fine burr and holds it much longer than ordinary card scrapers. Machined surfaces and edges come ready for sharpening and burnishing.