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Subject:
All you ever wanted to know ...

Derek Cohen (in Perth, Australia)
Barry, as Wiley and others have mentioned, there are about as many sharpening methods as there are woodworkers, and on fori it appears that everyone wants to tell you their version! :O YouTube is the worst offender, since many there are seeking their 15 minutes of fame.

It gets confusing and overwhelming after a short while, but this diminishes after 20 years or so.

I will try and keep this simple, with someone starting out with hand planes in mind.

1. The plane needs a coplanar sole (toe-mouth-heel). The area around the mouth must be evenly smoothed down. Start with 120 grit sandpaper and work to 240 grit. After this grade, once using the plane, the wood itself will polish the sole.

Use sandpaper glued to a flat substrate, such as glass ..

As you have found out, the more iron you remove, the greater the surface area remaining, and the harder it becomes to do more. Hang in there - it is tempting to stop just when you are nearing the end.

2. The blade: The bevel has two sides - front and back, and both must be hone. The back must be perfectly flat otherwise it is difficult to achieve a sharp edge. Essentially the same deal as the plane.

Lapping the back in pictures: http://www.inthewoodshop.com/WoodworkTechniques/Lapping%20the%20Backs%20of%20Blades.html

3. Sharpening media: With thin blades, it is possible to work with sandpaper, which is great because it is an inexpensive way to get going.

Get the feel for what you need to do by using a cheap Eclipse-type honing guide. Begin with grinding a flat primary bevel with 120 grit, jump to 240 grit, then 600 and 1200 grit. Finish on 2000 grit. The last 2 papers are wet-and-dry. Thin Stanley-type blades are doable with just a single bevel throughout. This is less complicating for the novice.

If you want to use diamond plates, the more durable are DMT, and you need a Coarse, Fine and Extra Fine, and then finish on 2000 grit wet-and-dry paper.

It is when you get to the thicker blades that you now must work differently. These modern blades are generally also harder, and attempting to hone the full face of a bevel is a fool’s errant. So either one hollow grinds (as I prefer to do) or one uses a secondary bevel (as per Rob Cosman). Hollow grinding is especially helpful to those freehand sharpening, and secondary bevels are where honing guides shine. Of course one does not preclude the other.

Grinding: The new way is to use CBN wheels - which I may have had a role in popularising :) Here is a link to an article if mine, which explains what it is about : http://www.inthewoodshop.com/WoodworkTechniques/UltimateGrindingSharpeningSetUp.html

I am not going to say more about this simply because it is for down the road, and at this stage you still need to prepare the plane, sharpen the blade, assemble the blade and position the chipbreaker, install then whole mess, and then learn to get the ideal blade extension. That is enough to overwhelm all and make the process appear too great! But in reality, with practice it all becomes second nature.

There are other issues which extend beyond sharpening and are critical to a satisfying plane experience: preparing the chipbreaker (both underside and leading edge), and positioning the chipbreaker on the blade. Yell out if you need input.

Regards from Perth

Derek

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