CABINET SCRAPERS

by Patrick Minervini

Basics

  1. Blades
    1. Thickness
      1. .50 - .60 Standard heavy blade for most aggressive cutting.
      2. .24 - .30 Hand Scraper Blade for finer more finish cutting.
      3. .15 Extremely thin cutters available through Woodcraft for applications such as a chair scraper and the finest cutting.
    2. Cutting blade stock
      1. Dremel tool with abrasive cutting wheel to score then snap.
      2. Nicholson Mill Bastard file to score then snap.
    3. Alternate sources for blades
      1. Old back saws ( .25 marked do not set on the blade) or old crosscut saw.
      2. Test can be performed to check for carbon content by using a grinder to evaluate the sparks given off. Lively, bright, aggressive sparks indicates high carbon good quality steel for scraper blades.
  2. . Sharpening basics.
    1. Lap back of blade on a fine stone.
    2. Draw file to 45deg. with a good file (Red Devil Scraper File)
    3. Re-lap the back on a stone.
    4. Lightly stone burs from bevel followed by light stone of back once again.
    5. Burnishing
      1. Lap back of blade on a fine stone.
      2. Lay the burnisher on the blade at the angle which has been filed, the raise it up 10deg. to 15deg. In one aggressive stroke, draw the burnisher to create the initial burr.
      3. Roll off the bur from the back with the burnisher.
      4. Establish the working burr following steps 1@2.
    6. To re sharpen after use, follow steps 3 + 4 only.

Sharpening Details

Equipment Needed

Placing a burr on a cabinet scraper

  1. File one long edge of the scraper to approximately a 45deg. angle. It is most important that the apex of the filed surface be as illustrated. To prevent flexing of the scraper, clamp it low in the vise. I the scraper is thick, (.50 - .80 mm ) this step may take some time. Also, it is not uncommon to achieve the desired angle at one end and not the other. This is usually due to uneven file pressure over the entire surface of the scraper. The length of the angled edge should be about twice the width of the scraper. The burr caused by the filing is not the burr you are trying to achieve.
  2. Remove the scraper from the vise and with a sharpening stone, flatten the back side of the scraper where the burr was created in the previous step. An effective way to achieve this is to place the blade on a flat surface and GENTLY rub the stone on the blade to remove the burr. The back if the blade should now be smooth and shiny like the back of a well sharpened chisel.
  3. Again, place the scraper low in the vise and, using the stone, rub over the filed angle achieved in step 1. Remove the blade from the vise and repeat step 2. with a final light pass of the stone to remove any remaining burr. The object is to create a well defined apex as shown in step 1.
  4. Clamp the scraper in your vise, and place your burnishing tool at the far end of the scraper at an angle of approximately 10deg. LESS than the angle you filed in step 1. Now, with one firm stroke, pull the burnishing tool toward yourself. It is important to use firm, even pressure over the entire length of the surface. Wetting the burnisher with a small amount of water will provide a smother action when the burnisher is pulled across the scraper. Use only one stroke since subsequent strokes may change the angle of the burr or weaken it. You should be able to feel a pronounced burr at this time.
  5. Remove the scraper and place it face down on a flat surface. Hold the burnishing tool FLAT on the back of the scraper and pull it toward you with one or two moderate strokes. You are trying to remove or flatten the first burr you just formed. This operation hardens the apex and smoothes the back of the scraper for forming the final burr.
  6. Place the scraper low in the vise and burnish the edge again as described in step 4. Now, you should be able to feel a pronounced EVEN burr over the entire length with your fingernail. If not, the problem may be that the apex was not even over the entire length of the scraper. Once you have the burr you want, proceed with the next step.
  7. If your burnisher has a sharp point. place it under the burr and apply a very small amount of pressure to the underside of the burr and (only once) gently draw it toward you. This action smoothes and polishes the underside of the burr. If the burr is not pronounced enough, the burnisher will not "ride" under the burr. The problem may be uneven pressure in forming the burr of the apex may not have well defined enough to create a burr. Return to step 1. It won't take but a few minutes to re-fill the apex and burnish the burr. The results will be worth the effort.
  8. Your scraper should now have a burr that will produce fine shavings and not dust. To recondition the burr, follow steps 5 through 7. After the burr has been reconditioned 5 to 6 times, it may be necessary to follow all the steps to replace the burr.