Crossbow Building Wiki


This article describes making of bow irons using a metal former around which the rectangular rod is bent while being heated with a blowtorch. This method is very convenient if you need to make several sets of bow irons. However, making the metal former is very annoying and slow job. So, if you need just one set of bow irons, you're better off following this process instead. Also, you really need a blowtorch to use this method successfully. Cold forging won't work and heat of a forge is difficult to focus to the correct area. If you only have a forge, the metal former probably has to modified somewhat to become useful.

Many thanks to Ville Huhta from Rautaportti Ky for providing the necessary tools, designing and making these parts with me and for taking the photographs.

Process step-by-step[]

Making the metal former[]

First take a piece of thick steel plate. The thickness of the plate is determined by two factors:

  • Thickness of the sideplate material. The metal former should be somewhat thicker than the sideplate material so that the latter can be forged around it easily.
  • Height of the slot for guards and wedges. If the slot is especially thin, you risk bending that part of the metal former while forging the sideplate. You can compensate somewhat by using thicker plate for the former.

Using 12mm thick steel plate for the metal former allows forging sideplates from 5-8mm thick steel rod without difficulty. This should cover most imaginable scenarios.

After choosing the material for the metal former plate, make a model of it's finished shape from thin metal sheet, cardboard or similar. It should have exactly the same dimensions as the inside of the finished sideplate. Alternatively you can make only one half of the model as shown below, use it to draw the outline of one side, flip the model over and draw the other side:

Making the sideplates 2-1024x768-01

Making the sideplates 2-1024x768-02

After drawing the outline of the sideplate, add some extra to it's end (see picture below). This helps a lot when attaching the former to a vise.

Making the sideplates 2-1024x768-03

Next cut away most of the excess material with an angle grinder. The result should look like this:

Making the sideplates 2-1024x768-04

After cutting grind the metal former to shape. An angle grinder can do the job just fine, but for the final touches a bench grinder is more convenient. The resulting metal former should look similar to this:

Making the sideplates 2-1024x768-06

Notice the enlarged part at the end. As said above, it makes attaching the metal former to a vise much easier.

The last thing you need to do is drill a large hole for the sideplate rod into the enlarged part from the side. By inserting the rod into the hole the sideplate stays firmly in place while forging. This idea is well illustrated in pictures shown below.

Forging the sideplates[]

Now that the former is ready, making a sideplate is trivial. Insert one end of the rod into the hole you drilled, heat the area near the hole and forge the rod tightly against the former. Proceed slowly by heating an area, forging it to shape and then moving forward and repeating the process.

Making the sideplates 2-1024x768-14

Making the sideplates 2-1024x768-15

When you've about to forge the front end of the sideplate, rotate the metal former in the vise so that the forged portion of the sideplate presses tightly against the former. Doing this results in tighter fitting sideplates. This configuration is clearly visible from the below pictures:

Making the sideplates 2-1024x768-16

Making the sideplates 2-1024x768-17

After forging the two frontal bends switch the metal former into it original position and forge the other long side. The sideplate should look like this after forging:

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Making the guards 2-1024x768-06

Now cut away the extra stuff from the end of the sideplate:

Making the sideplates 2-1024x768-23

Once the sideplate is cut to correct length, make a "stopper" from the same steel rod. Then insert the stopper between the ends of the sideplate and put the whole package into a vise as shown below:

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Making the sideplates 2-1024x768-19

Next grind shallow grooves on both sides of the stopper. These grooves make the welding seam much stronger:

Making the sideplates 2-1024x768-20

After making the grooves weld the stopper and the sideplate together:

Making the sideplates 2-1024x768-21

Next remove any extra material left from welding. The end result should look similar to this:

Making the sideplates 2-1024x768-22

Once you've finished two sideplates, follow the instructions given here to ensure the sideplates match each other as closely as possible.