Sharpening Scrapers

[Dolamon]

Sorry to put this up on the site ... There was a nifty web site which explained how to set the burr on scrapers. Do any of you know where this is or how to do it? These are for the large flat and curved scrapers made from tool steel.

Thanks - after three unsuccessful days scouring the web, I thought I'd try here.

[Chris Baird]

I'm not sure of a URL but here is how to draw a burr. I use a block of wood with a rabbet cut in it such that a file can be held in the rabbet and stick out about 1/4 ". This ensures that file is 90 degrees to the flat of the wood block. Use this wood block and file to get a perfect 90 degree edge on all parts of the scraper. Then take the same block and just butt the scraper against a side and run it up and down a sharpening stone to hone the 90 degree angle smooth. Then put the scraper flat on a table about 3/16 from the edge and take your burnisher and hold it so that is touches both the edge of the table and the edge of the scraper. Pull the burnisher across using about 3-5 pounds of pressure and make sure you hear a "click" as the burnisher comes off the end. Do that to both sides. Now hold the burnisher perpendicular to the edge of the scraper and draw it across with about 3-5 pounds of pressure and again listen for the click. Thats it.

[sunburst]

How you sharpen a scraper depends a little on what you want to use it for.
You mentioned turning a bur, so I'll start with that.

First thing to do is get a square edge. Remove any old bur by filing it off with a smooth cutting flat file layed (lain?) flat against the side of the scraper. After that, file the edge square to the sides. You can turn the bur now, or you can refine the flat surfaces with a sharpening stone so they are very smooth. You can do fine work with the scraper after the stone without a bur.

To turn the bur you'll need a burnisher. Clamp the scraper in a vice and lubricate the square edge very slightly. The best way I've found to do this is to rub your finger on your forehead or beside your nose and then rub it on the edge of the scraper.

Start burnishing with the burnisher held at 90 degrees to the scraper and run it along the length of the edge very lightly at first, then with increasing preasure. You should feel the steel getting smoother.
When the edge starts to feel nice and smooth, start to roll the burnisher over to the side a little at a time to form the bur. How much bur you want depends on the job ahead for the scraper. It takes some trial and error and some practice, so try several times and experiment.


I see Chris got his reply in while I was typing, same principle, different details.

[Dolamon]

Thanks both of you ... these are both much more coherent than that lost web site. I really appreciate it! I've even used Gem Razors as scrapers to pull off or blend too thick stain or shellac, but I forgot the small details which make sharpening the big blades a more logical job.

Thanks again - Dion

[John Jesseph]

http://www.brendlers.net/oldtools/scraping/scraper.htm

don't know if this is what you were looking for.....

[Dolamon]

THAT'S IT! Thanks John - It really covers the curved scraper problem and - the intermediate honing to true.

Outstanding!