Derek Cohen (in Perth, Australia)
+1 on that, but let me play advocate a little...

Hi Tom, all good points, but I will return your serve ...

Let me add that for me it is less about the materials, there are better materials, maybe, than wood. To me it is about the different formats, and the wedge etc... format is just better.

A number of my steel planes are designed with wedges, and so the format is the same. I do not differentiate the planes according to format as adjusting a wedge is for me about the same effort as adjusting a mechanism. The materials therefore are part of the difference.

Extra weight is always bad. Planes that need more weight to plane well are simply badly designed. A well designed plane use geometry and design, rather than weight. And weight not only tires the planer out, but reduces speed. Speed is part of the secret to planing since cutting power increases to the square of speed. More cutting power improves the quality of the cut, or the speed of stock removal.

I do not see extra mass as a way of compensating for a poor design. I see extra mass as aiding in planing especially hard woods. Mass aids in creating momentum. This is not in place of a sharp blade, but an addition to it. While we have been discussing and advocating the chip breaker effect, mouth size also has a part to play, and mass adds to the part played by a small mouth.

Two of my favourite woodies (that I built) ..

15" Jack plane in Mesquite (this uses a 5/16" thick 2" wide D2 blade):

36" Jointer in Jarrah (3/16" tapered 3" wide Berg blade):

And a light BU infill I built from a Stanley #3 (this has a 25 degree bed)..

Regards from Perth

Derek