Monday, April 4, 2011

New Life for a Centenarian Plane

Varvill  & Sons was one of the UK planemaker most active between the late '800 and early '900.

This  smoother plane was built likelihood in the last two decades of the nineteenth century. It has a metal sole and a rear handle, screwed into the back of the body. Hard to say if the metal parts are original or homemade, though some rough details lead more to the latter option. The plane conditions were quite good; this allowed the easy repair and tune up. The beech handle had a break at the top, which occurred where a knot was present. I  removed the broken part and replaced it with a new piece of same wood,  then colored like  to the old beech. The metal sole was slightly bowed in the length, probably due to the wood movement. I removed the screws and smoothed the wood with another plane. After installing the metallic sole, I corrected it on sandpaper attached to a flat surface. Another issue concerned the mouth width. Almost 2 mm, definitely too much for a smoother. I  therefore decided to reduce the opening by inserting a couple of veneer pieces on the seat.  I sharpened the blade with a 30° secondary bevel, flat edge profile, blunt on both sides.

The plane works fine but I have some general concerns regarding its hybrid structure.
The  metal sole is not as great in the smoothness as wood, but is certainly an advantage for two reasons:
1) It adds weight to the plane, useful for cutting with very little iron.
2) The sole resists to the wear and has not need of frequent maintenance.
 The  first point seems irrefutable. For the second one is necessary to say that the presence of the metal sole  prevents natural wood movements and can easily lead to cracks in the plane body, and it is not flexible enough to prevent any warping especially along its length.

If  planing the underlying wood is a solution to restore the flatness, the wooden mouth increases its amplitude and the opening for the chips will be larger. But even if this does not  happens, you have to deal with the tapered blade profile, so  that when it is sharpened it decreases its thickness still leads to a wider mouth. In a full wooden plane a larger mouth is repaired by placing a patch to restore the exact opening width. This is not easily possible with a metallic sole. The repair done with shims placed on the seat can slightly alter  a perfect wedge insertion. Even the handle has advantages and disadvantages. The advantage is a comfortable grip, but at the same time it is an obstacle to beat with a mallet on the plane back when you have to remove the cutting unit.
One is inclined to beat on the handle and perhaps this was the cause of its break.

No comments:

Post a Comment