I have recently been wanting to try out fencing with full sized shields with the Blackhearts Fencing Club, so I am making one shield for myself and one for the club. This style is called a heater shield, although that name is not contemporary to the period, the style was so ubiquitous that they would mostly just be called shields at the time. These shields were often slightly curved along the width, the curved shape adds some rigidity (in the same way corrugations add strength to cardboard) and make it so things like spears, arrows, or thrusts from swords will more easily be deflected off to the side instead of digging into the shield.
The fist step I took was to cut 4 pieces of 1/4" oak plywood to roughly 2’x4’ with the grain running lengthwise on half and widthwise on the other half (this will be important for durability since the shields will see actual use, if they are just decorative the grain direction is irrelvant). My cuts were pretty sloppy, unfortunately the sawstop was down at the time I got my plywood and I cannot transport a large 4’x8’ sheet easily to bring it back after the saw was fixed so I had to clamp a straightedge to the board and use it as a guide for a circular saw, and the saw shifted on me a lot.
Next I made a bending jig that simply consists of two 4’ 2x3s stood up on edge spaced 2’ apart from outside edge to outside edge with a couple of scraps of 2x6 screwed across them to hold them parallel. The specifics don’t matter much here, the rails could be any nominally 2" construction lumber on its face if you didn’t mind the curve being a bit shallower (although much deeper than a 2x3 on edge would likely be too much curve and may crack while bending) and the cross boards could be anything you happen to have around.
Next I laid one of my pieces of plywood with the grain running lengthwise onto the jig, spread a layer of wood glue over the whole surface, then stacked one of the pieces with the grain running widthwise on top, then I put a board down the middle and stacked as much weight as I could quickly find on the board to curve the shield. The alternating grain direction helps with splitting resistance, if any thing hits one layer from any direction and bites in enough to apply a splitting force separating the grain it will quickly hit the next layer with the grain running in the opposite direction and meet a lot more resistance because the grain needs to be cut through or ripped apart with tension instead of merely forced apart. Unfortunately I didn’t have anything the proper length that wasn’t too wide, so I had to stack some shorter 2x4s I had laying around to distribute the weight, this caused issues later, if I did it again I would run to the store and buy another 2x4 to do it right. With the first attempt I didn’t have enough weight to get the amound of curve I was looking for, so the second time I used some ratchet straps to help it along.
after gluing up both of my blanks I noticed that I had a lamination failure on the second one, which was more aggressively curved. I couldn’t squeeze the layers back together because the glue did bond on the sides and in t center along the length (the gaps were only at the ends, they didn’t run the full length, so the wood would need to stretch to fill that gap)
This was probably caused by my stack of short 2x4s instead of one properly running the full length, the force of the weight and ratchet straps squeezing down didn’t get spread out to the ends of the boards properly so the outsides of the bottom boards lifted up into a slight V shape, which allowed my layers to separate on the outside ends. I planned to try to fill in the gap with spray foam, but decided to lay out the outline and cut it to shape first so I wouldn’t need to get the spray foam as deep between the layers because that seemed likely to leave me with voids. Luckily after cutting some of the material off of both ends the gap on the top end of the shield closed up completely and on the other end it changed from one big gap running most of the width to two gaps but the center and sides were bonded, and this was much easier to fix because there was enough flexibility to squeeze the gaps closed. My picture isn’t great here because it was taken off center but I can’t go back and take another at this point so it will have to do.
After cutting out the shape with a jigsaw I did some reshaping to clean up where the saw didn’t leave me with quite the shape I wanted and broke all the sharp edges with a saw rasp to keep them from breaking and so that they wouldn’t rub through some of the other parts that will be added later, then I dripped a lot of glue into my gaps and clamped them shut.
Now I am waiting on the glue to cure, which could be quite a while because the glue is so deep between layers.
The next steps will be to glue a layer of canvas onto the outside face, which should help to further strengthen the shield and make it more paintable, then I will cut the appropriate straps and rivet them on, as well as tack on a pad for the arm with some upholstery tacks, then paint the surface, and finally I will wrap the edge with rawhide to further reinforce it against splitting