If you didn’t get a chance to purchase one of the Crucible curved card scrapers, you can make your own with a dry grinder and an existing card scraper. It takes about 30 minutes.
Download and print out the following template. It’s a hand-drawn version of Chris Williams’s scraper, which is where our design started.
Cut it out and affix it to your card scraper with the help of spray adhesive. Or make a cardboard template and trace its shape on your scraper with a permanent marker.
At your grinder, set the tool rest to 0° – parallel to the floor. Dress the wheel of your grinder (we use an #80-grit wheel, but a #60 or #100 will also do) so it has a slight convex shape. This convexity in the wheel makes the scraper easier to shape.
Get a bucket of water and put it by the grinder.
(Hey wait, where are the step photos? I’m in a hotel room that’s 400 miles from my shop. You are going to have to use your imagination.)
Place the scraper on the tool rest and start grinding the excess metal away. Don’t work on one part of the scraper for more than a few seconds. Keep moving around the perimeter. After 10 or 15 seconds, try to pinch the scraper with a finger and thumb. If….
… you can pinch the scraper with no pain, continue to grind.
… your fingers reflexively jump away, cool the scraper in your water bucket.
… you smell bacon, also cool the scraper in the water bucket.
Once you have ground down to your line, you will have become pretty good at grinding flat shapes – congrats. Now you need to remove the grinder marks from the edges.
Use a block of wood to hold the scraper at 90° on a coarse diamond stone and stone the edges. Remove all the scratches from the grinder. Then move up to a #1,000-grit waterstone (or soft Arkansas) and then up to a polishing stone. Then you can proceed with normal scraper-sharpening procedures.
This is exactly how I made all of our prototypes. I promise that you will become emotionally involved with your scraper after putting all the work into it, and you might not ever want to buy one of ours.
So be it.
— Christopher Schwarz