Wood Tool Sharpening - Chisels and Plane Blades

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Details

Woodworking tools MUST be sharp for proper use. This is a foundational skill that you must learn to gain competency and confidence with your joinery. To sharpen, we have the following tools available:

  • Veritas jig
  • Diamond stone
  • Stropping leather

Chisels (the Narex ones) or hand planes with a green band MUST be sharpened using the standard SLMS sharpening method outlined below. That is a 25° primary bevel, a 30° secondary bevel, and a perfectly flat, polished back. See details here. Please make sure to thoroughly understand the contents of this page. If you choose not to follow this process, you are creating extra work for other members.

Induction and Training

No formal induction. Please reach out for guidance if you’d like to learn.

As mentioned above, the we sharpen the Narex chisels and hand planes in a standardized way at SLMS. This is to keep those tools in good condition, and have a simple, easy to replicate process that works and all members can use.

The following diagram shows the anatomy of a properly sharpened chisel/plane blade following this method:

drawing

  • Primary Bevel: the purpose of the primary bevel is to remove material and make it faster and easier to sharpen. The primary bevel should only need to be touched up occasionally. The primary bevel should be ground to 30°. Don’t try to grind the primary bevel until after you’re comfortable with touching up the secondary bevel.
  • Secondary Bevel: this is the cutting edge that you will be grinding to sharpen the blade. Most of the time, you should only have to quickly touch up the secondary bevel to get it sharp. The cutting edge is the meeting point between this bevel and the polished flat back of the blade. The smaller the secondary bevel, the faster and easier it is to sharpen the blade. The majority of the time
  • Polished flat back: the back of the blade must be perfectly flat. If it is not, you cannot get a sharp edge. On chisels, if the back is not flat, the chisel will also not cut as accurately. Pay special care that you are not accidentally adding a bevel or otherwise un-flattening the back of the blade.

Photos of process forthcoming:

Maintainers

@woodtechs

Risk Assessment

Identify risks
State control measures

(Note: The following is effectively the contents of the induction process, if it exists)

Before Use

Make sure you have water and a rag available.

Secondary Bevel (Normal Sharpening)

Section in progress

We have the Veritas Mk. II Honing guide and 1000 grit diamond stone available to sharpen the secondary bevel to an exact 30° angle. There is a strop and polishing compound to wrap up the process and get the blade razor sharp.

lapping. The back of the blade should be completely flat. If it is not, the blade will never become truly sharp. Visually inspect it - move it in the light and make sure that the polished flat back is all in the same plane all the way up to the edge.

Insert picture of a positive and negative example

Touch up the flat back of the blade by lapping on the 1000 grit stone with water. Make sure to bring the blade to the stone last. Place pressure on the blade only where it touches the stone (don;t lift the handle). Move If this is not clear, please watch the video

Don’t lift the blade and proper way to place on the stone

setting up the jig.

Make sure the blade is square against the guide and all the way up against the stop, or else you’ll be grinding a completely new edge onto the blade.

Primary Bevel

Don’t attempt to re-grind the primary bevel until you’ve learned to grind the secondary bevel and fully understand the theory behind sharpening. It’s easy to massively screw things up here.

You should only have to regrind the primary bevel occasionally, when the secondary bevel has traveled about halfway up the primary. The preferred method of reestablishing the primary bevel is to use the SE-77 jig on the Tormek. Review the documentation in the Tormek guide (page 120) for proper setup. Once you’ve learned how to do this, it only takes about 2 minutes to fully set up and regrind the primary bevel, but is a bit involved to learn the first time.

  • Mount the US-105 Universal Support in the vertical position and over the grinding wheel. It should already be on the Tormek, but may be in a different orientation.
  • Slide the internal safety stop ring onto the Universal Support. Should be on the SE-77 jig, but may be in the box under the Tormek.
  • Slide the SE-77 jig onto the Universal Support. Should be in the box under the Tormek.
  • Unscrew the external safety stop from the jig and screw it into the end of the Universal Support
  • Fix the chisel/plane blade into the SE-77 jig. Review the Tormek manual page 120 to for further details. Slide the moveable tightening screw close to the edge of the blade. Make sure you have an even clamp across the blade Make sure you didn’t put it in upside down!
  • adjust and tighten the internal safety stop. The jig should slide such that the blade can travel over the full width of the grinding stone (you don’t want to carve a groove into it) without accidentally pushing it off the wheel.
  • Loosen the height screws holding the Universal Support in place. Use the WM-200 guide to set the angle of the jig. Make sure the dial on the left is pointing to the wheel diameter, and the dial to the right is pointing to 25°. Spin the twisty thing on the Universal Support with numbers on it to raise or lower the Universal Support until the right half of the guide lies flat on the back of the blade, and is placed where the wheel meets the blade, like in the picture. Retighten the screws to lock the Universal Support in place.
  • Put water in the tank and raise to the grinding wheel

Video for reference: Tormek Square Edge Jig Instructions

During Use

Tormek - Primary Bevel - Make sure to keep the blade moving. Don’t cut a groove into the wheel. Grind until you’ve completely cleared the old secondary bevel away.

After Use

Please re-flatten the fine grit stone with the diamond plate, and wipe down the sharpening stones to prevent rust from forming.

Tormek - Remove water from grinding stone. Remove the external safety stop and screw it back onto the SE-77 jig. Put the jigs away. Re-flatten the stone if you’ve cut a groove into it.

Maintenance

References

Videos:
Matt Estlea: How To Sharpen a Chisel
Matt Estlea: How To Sharpen a Plane Blade - Do not use the ruler method he mentions (it adds an extra step for people, and we want to aim for consistency), but otherwise an excellent overview of the principles used in sharpening. The grinding of the primary bevel should be a rare occurrence. Reach out to @woodtechs to understand how the material in this video maps to the tools we have at SLMS.

Tormek SE-77 guide: Tormek Square Edge Jig Instructions

Manuals:
Veritas mk II Deluxe Honing Guide Manual (PDF) (645.3 KB)

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