Building a Dovetailed Infill Panel Plane

Jim Yehle - Salt Lake City - April 2004

Design Notes

This panel plane is the infill-plane equivalent of the Bailey-style jack plane, with a sole length of 14". I based the side profile on the elegant curves of Mathieson's panel plane, but it has an adjuster and closed tote more like the Norris A1. The front cushion bun is larger, again closer to the Norris than Mathieson or Spiers' designs. I chose 2" wide iron for the version of the plane documented here, which is narrower than the 2-1/4" typical of this type of plane, but variations are easy: you can modify the design by widening the sole, throat plate and infill (but you might want to keep the width of the square "tower" that the cushion bun sits atop at 2", lowering the parts of the forward infill which flank the tower to follow the curve of the metal side). I did produce a set of parts for a friend which will take a 2-1/4" iron, and added 1/2" of length to the front and back of the sole to mimic the jutting look of the Norris panel planes.

I made the sole by hand-peening double-dovetailed steel plates together, then filing and lapping everything smooth, in the traditional manner pioneered by Stewart Spiers. But I had the modern conveniences of computer software to help me with the design, and a machine shop equipped with a CNC milling machine and metal-cutting bandsaw. This plane can be made as I did it, or cut and filed by hand like Jerome Schueller did. Wayne Anderson also makes exquisite infill planes commercially by hand.

I saved some time by purchasing an adjuster and lever cap from Bristol Design in England. These parts are also available from St. James Bay, Ray Iles, Spehar Toolworks, and others. My current favorite adjuster is from Darryl Hutchinson, who has also supplied me with some nice A2 irons.

The following description lacks some of the depth of the writeup about a plane I built earlier. For a wordier account of building an infill smoothing plane, I refer you to that article.

Drawings

The following drawings are in PDF format. If you want to print the drawings, you'll get better results by downloading the Vellum drawings and a viewer program. See details on the download page.
Assembly Overview

Full size (legal paper) Side profile
Dimensioned Sides and sole

Full size Infill profile

Pocket for Bristol Design adjuster

Iron and Back Iron (sized for Bristol adjuster)

Lever cap location (Bristol)

Link to materials list, excluding tooling, which is mentioned in my A13 Materials List
Link to machining details

Assembly

Double dovetails showing parabolic secondary splay milled into sole
The peening buck, whose sides milled to splay out 0.6° in anticipation of springback
Sole placed on the buck
Clamped and ready for peening
Peening double dovetails: before and after
Peening finished, shell removed from buck, starting to file. Rough filing goes across, then start draw-filing when excess metal of tails is flush, using finer files.
The fun part! Dovetail joints disappear as you file them.
Filing sides flush. Note guide for end of file, to keep from marring upper surface.
Trial infill pieces, made from scrap to test feel and fit
Smoothing bandsaw marks from bun using belt sander
Final bun, roughed from East Indian Rosewood
Rear infill profile, rough-cut with bandsaw, Forstner bits and jigsaw

Hogging rear infill to tote width using plunge router

Router base rides on still-attached offcuts

After plunge-routing to tote width (below)

Rough-rounding the tote, using roundover bits in router table. I used a 3/8" radius for the front and rear edges of the handle, and a 3/16" radius for the front and top edges of the finger opening. (Both of these router bits are flush bearing guided.)
Final tote, in solid East Indian Rosewood

The full-width portion of the rear infill will get trimmed flush with the metal sides later.

I made my own adjuster and lever cap when building a previous infill plane (see A13 Infill Smoother). It was a lot of work. This time, I bought commercial parts. If using an adjuster from another vendor, you may need to customize its mortise in the tote so that the size, shape and position is correct. The location of the back iron screw must match the position of the adjuster's banjo so that the adjustment range of the iron is good. Also, the lever cap pivot needs to be positioned so that there's enough clearance under its screw to slip the iron, back iron and screw between it and the bed. I came up with the oddball pivot arrangement to allow me to remove the lever cap entirely (e.g. to fiddle with the adjuster). It would be much easier to rivet a solid shaft in place. Jim Kingshott used a spring-loaded pair of stepped pins to release his lever caps.

Bristol Design adjuster
Mortise in tote for adjuster Adjuster in its nest

Drilling cross pins. I used a spotting drill, then a #16 twist drill (.177" diameter), followed by a .1855 reamer, then a countersink. The rod's diameter I used was .185, so the interference fit I usually try to achieve didn't happen, since I lacked a .184 reamer.

Brass spacers/liners through which the cross pins are installed. The length of these brass tubes should be exactly the width between Inside faces of the shell's sidewalls. A piloted counterbore is helpful to keep the larger-bored hole concentric with the initial bore. (Pilot size = 3/16, countebore size = 1/4")
Shaving down the lower edge of the finger opening
to final shape using a back-bent gouge.
Bringing the bandsawn "rear deck" flush

The short top-bearing-guided flush trim router bit I use: Eagle America 102-1002B "Dado cleanout" bit. It takes two passes.
Trim router, jigged for flush trimming. Note the complementary wedges (table leg taper offcuts, actually) held together so that the free-hanging side of the router base can ride on something. Sliding the pair of wedges lengthwise against each other gives you precise control over their combined thickness. After the first pass, remove the thin fin, taking it down to flush with the metal side (and the infill wood below). Now you can make the second pass, the bearing being guided by the cut you just made. Setting the depth of cut is obviously important before the second pass.
Bristol Design lever cap, with pivot shaft made from shoulder screws and a hex threaded spacer ("coupling nut").
A bit of brass had to be milled from underneath to allow clearance for the hex coupler to fit into.
When assembled, the screw heads pivot in holes drilled and reamed into the plane's sidewalls.

Infill riveted, sides filed, lever cap and blade guides installed. Only after flattening/lapping/polishing the sole do you file open the mouth.