Medieval Crossbow From an Old Joist

About: I love carpentry and woodworking.

This is my homemade medieval crossbow, made with fir wood from an old joist and a 120 pounds bow that I bought in a crossbow spare parts store. Yo can also buy the bolts and the string in this kind of stores.

Here is the most of the material I used in this project:

- Long piece of reclaimed wood (I used fir wood from an old joist) 2 x(85*6*2,5)cm

- Wood screws

- A cilindric piece of aluminum (2,5 long x 4cm diameter with 5mm hole in the center) and a brass bar about to 50 cm long, bot pieces to make the trigger mechanism.

- 120 lb replacement bow, it's made of compressed fiberglass and it costs about 25$ with his string, but you can make your own bow with reclaimed materials, live PVC, or steel bar.

- A piece of iron (2,5 cm * 50 cm * 2 mm thickness) to make the foot stirrup

- Files, sand paper, electric sander, saw and electric saw, drills, wood glue, etc.

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Step 1: The Trigger Not

The first thing I did was the trigger system. I used a cilindric piece of aluminum, and I shaped it as shown in the sketch: 4 cm diameter, and 2,5 cm long, with a 5 mm hole in the center of it.

Then, with the hand saw, I did the shape of the not as you can see in the last photo.

Step 2: The Trigger Bar

To make the trigger bar, I used a brass bar (aprox. 50 cm) molded as you can see in the photo, with a 2 mm hole to make it pivot.

Step 3: The Crossbow Body

To make the body of the crossbow, I used a piece of fir wood, as you can see in the image, I need a lot of work and tools to make the pieces cause I took it from an old fir joist.

The result are two similar pieces, 85x6x3 cm, you can shape them in your own way.

In the last photos you can see the carved place in the body of the crossbow to install the trigger mechanism and the two possitions of it.

Step 4: Shape and Sanding the Two Pieces As One

Once you have the two pieces of wood properly carved for the trigger, you have to shape them as you wish and make a good sanding work. I used electric sander and electric saw to make the shape as you can see in the image.

Step 5: The Holes for the Trigger Not and the Bow

The hole for the trigger was carved in each piece of wood, and then I adaptated it when the two pieces where together.

In the case of the hole for the bow, I used a drill to make the place.

*Note: That's not the final stirrup, is just a piece to take measurements.

Step 6: The Stirrup

I made the stirrup from that iron bar, I used a pice of 50 cm, the place for the feet is 12 cm long.

Step 7: Varnishing

Step 8: Montage of the Trigger

That's the way to mount the trigger system before you glue/screw the two pieces togheter.

Step 9: Montage of Stirrup and Bow

Step 10: Final Adds and Reinforcements

Well, I just net to add a reinforcement for the trigger not, I didnt carved any place to the arrow or something like that cause I did my shoot experiments and it works really good. I have to say that 120 pounds is too far enough, In fact, is really hard to charge the weapon.

Step 11: My Result

And finally, thats the result, I'm pretty glad of it, and I hope you can have the same fun as me building this project. Is really fun to shoot with it. I have to say that safety is the first ;)

Hand Tools Only Contest 2017

Participated in the
Hand Tools Only Contest 2017

Reclaimed Contest 2017

Participated in the
Reclaimed Contest 2017



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    5 Discussions


    1 year ago

    Your aluminum roller nut will wear out with a steel rebar tickler. To ensure longevity, you should drill and tap a hole where the tickler meets the nut, within the nut. Inset a screw and grind it flat with the contacting face of the nut. That way you have steel on steel to help with wearing. Traditionally, they used an iron rod or plate in that contact point if the nut was made of horn, bone, or bronze and they used an iron tickler.

    1 reply

    Reply 1 year ago

    Thanks for the useful info, I have to say that i though about that when I was building the trigger system, but I didn't knew the strategy you talk about. For now the nut is ok, without any scratch or damage, but you are right, if I use it too much, it will be damaged, so I will reinforce it with steel.


    That is a really nice looking crossbow. Thanks you for sharing.