Academy Notes and Tips - Clean Cuts

Academy Notes and Tips

MAR/APR 2004
Volume 47/Issue 2

IN THIS ISSUE
Project Articles
• Strip Laminate Bending
• The Turned Hall Tree
• Two Great Kitchen Gift Items

DEPARTMENTS
• Ask Smitty
• Owner’s Gallery
• Letters from Owners
• New Baby Workshop Calendar

Academy Notes
Clean Cuts - Pt. 5- Sharpening Jointer, Molder & Shaper Knives

Service Pointers
Troubleshooting the Shopsmith Lathe Duplicator

Safety Tips
Safety Cans for Flammable Liquids

What's New
Check out our New Shopsmith Website

EDUCATION
• Find A Shopsmith Woodworking Academy Near You
• National Woodworking Academy in Dayton, OH

ONLINE CATALOGS
• Online Accessory Catalog
• Request Printed Accessory Catalog
• Online Replacement Parts Catalog

MARK V INFORMATION
• Find A Shopsmith
MARK V Demo Near You
• Request MARK V Information Package

LINKS
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• Free Woodworking Tips

FEEDBACK
Contacting Shopsmith

From the Shopsmith Woodworking Academy
Clean Cuts -- Part 5--Sharpening Jointer, Molder & Shaper Knives
Printer friendly PDF copy of article (607K)

IMPORTANT: When performing this operation...whether using Shopsmith's Planer/Jointer Knife Sharpener or this shop-made jig...start with your nicked Knives and be sure to count the number of passes you make over the Sanding Disc. All Knives should receive the same number of passes in order to maintain proper Cutterhead balance. If you remove more material from one Knife than from another, an out-of-balance situation will exist, resulting in bothersome machine vibrations.

Check your Knife's edge frequently to be sure you've removed all of the nicks. Use a straightedge to ensure that the Knife's edge is straight and true. Remove the Knife from the jig and hone it with a medium grit India (or similar) stone. Follow-up with a Hard Arkansas stone to remove any burrs.

After regrinding all of the Knives, install them in the Cutterhead according to the procedures outlined in your Jointer Owner's Manual.

Shaper & Molder Knives
Like the Jointer, most Shaper Cutters and Molder Heads use three cutting edges...and because of the way they're ground, it's relatively simple to keep them sharp without changing their profiles.

Start by using a flat stone such as a Medium or Fine India or a waterstone. Use plenty of lubricant (oil or water) to keep the stone from clogging-up with swarf.

Hone the faces of the Cutters often, with just a few strokes on each. Again, be sure to count the strokes as you go to be certain you're honing all three edges equally. Should a burr form on the profile, use a Hard Arkansas slipstone to remove it with just a few light strokes.

Fig. 7. Honing a Molding Knife. Hone only the profile section of the Knife. Use the same number of strokes on each knife in the set.

While you may want to hone the entire surface of the Molder Knife's face side on the stone, It's important to remember that repeated honings will reduce the thickness of the Knife, potentially allowing the Knife to become loose in the Cutterhead. For this reason, you should hone only the profiled section that extends outside the Molding Head (See Fig. 7).

Fig.8. Use the edge of a stone to hone the entire face of Shaper Cutters.

When honing the three-wing Shaper Cutters, use the well-dressed (sharp, 90-degree) edge of a medium or fine grit oilstone or waterstone. With all profiles (especially the ogee), use care to hone the entire profile (See Fig. 8). Again, count the number of strokes and be sure to use the same number on each cutting edge. Remove the burr with just a few light strokes of a Hard Arkansas stone.

Final thoughts
Jointer, Shaper and Molder Knives should always be as sharp as possible. Check them frequently by carefully drawing the cutting edge over your thumbnail. They should grab slightly and leave a light track. A Magnifying Lamp will help you spot small irregularities in your cutting edges.

Sharpening these tools helps you grow in your respect for them. As with all power woodworking tools, you should have a healthy respect for the danger they can pose, if not properly cared-for.