Friday, April 24, 2015

Open-Source Hollows and Rounds: Bodies

In the quest for a modern user set of hollows and rounds, the desire is to jump in and address the body. Likely, most of the opportunity lies in the iron. Still, it doesn't hurt to start thinking about bodies that might work well. To that end, I'm excerpting some images from a pretty good book I picked up when I was fortunate enough to visit a Lee Valley store.
Also if you haven't already read everything at and seen the Larry Williams video, that's solid baseline information.

One example from this book ends up with similar geometry as English planes, but creates the mortise by laminating strips on the outside.

In the next example (opening bouvet image) from Roubo we see the construction even more simplified, with the mortise being completely open on the side. (Dig the horn and the side facing wedge too.) I do wonder how bulky this style would need to be on wider molding planes, or if there is a tendency to warp away from the open side causing tracking issues.

The next 2 show construction that is quite different, in that they have a mechanism built-in that allows the toe & heel to move relative to each other. Neither are side escapement planes, but it's not a stretch to see such implementation.
The first shows using this motion to restrain the iron, replacing the wedge with a simple inexpensive carriage bolt. Dowel pins of a sort are used to keep the 2 parts aligned. 

In the second, the wedge secures the iron as typical, and the heel-toe motion allows mouth adjustment (much less important in molders) The alignment is controlled via the simply created dados in the toe and laminated construction.
In all these examples, you see that the iron continues all the way through the body or you'd have no way of reaching it for proper setup. As I look at these, I see some opportunity to simplify without sacrificing usability, of course I'm not a plane making expert by any stretch of the imagination so feel free to add to the discussion and/or tell me I'm on the wrong track.


  1. Perfect timing, Jeremy! I was actually thinking of starting a pair of H&Rs based on Roubo's photos today.

    Your opening pic is from plate 18, and plates 19 and 20 have more details on this construction. Plate 19 especially for hollows and rounds. It looks like the plane blank should be at least twice as wide as the blade. This might make some of the bigger ones a bit bulky, but there might be something one could do.

    For blades I bought some O1 tool steel bars from McMaster Carr, and the only metalworking involved will be to cut them to length and shape the blade before hardening. Unless I feel like going through the trouble of tapering the blades, but I think I will try it without to start, as part of the point of this exercise is to keep labor down to a minimum.

    1. Plates 16 and 17 also show some of this type of plane. It is curious about the wedge. Some of the planes show it being as you describe, and some show what we would recognize. The tongue and groove plane has one of each! Perhaps it has to do with the thickness of the wedge.

      I am only working from the "Book of Plates." Perhaps someone out there can translate what Roubo has to say on this subject?