Abrasive paper and double-side tape: together for flattening

Abrasive paper attached to a flat surface is an effective way to flatten the soles of metal planes, significantly improving their performance. I usually use spray adhesive, which provides a strong yet reversible bond, making it easy to replace the abrasive when it's worn out. The only drawback is the glue residue left on the glass plate, which must be cleaned with alcohol each time.

An alternative is to use double-sided adhesive tape. It offers excellent grip, leaves no residue on the glass when removed, and allows for quicker replacement.

If you can't find a full sheet of sandpaper wide enough, you can join two narrower strips together. The tape's thickness is minimal and doesn't affect the level of flatness needed to achieve a well-leveled surface.

Repairing a damaged plane body

Old metal woodworking planes are tools that often span centuries, continuing to bring satisfaction to those who use them even today. When damage occurs accidentally, the person responsible often feels deep guilt for interrupting a century-old life. The only partial consolation is a well-done repair.

The accidental fall of a cast iron plane often causes damage at its weakest point: the sides, near the mouth. This happened to my Stanley #3. After considering various suggestions, I developed a method to repair this type of damage—simple yet effective. By properly clamping the plane body to prevent any movement, we can drill 4 mm holes (slightly larger than the electrodes, which measure about 3.5 mm) along the crack.

At this point, the cast iron is properly heated using a torch or another heat source, and arc welding is performed. I used a small inverter welder with specific electrodes for cast iron. It's actually easier to fill the drilled holes than to weld a concave groove, which requires more experience. (In the photos, I forgot to take a shot immediately after the welding.)

I then proceeded to flatten the sole and sides, which were already almost perfectly aligned. And here it is—restored to its former glory (or almost)—ready to produce its usual thin shavings.