The renovations in our apartment have finally come to a phase where I have been able to resume work on my cheiroballistra.
A few days back I finished attaching the triggering mechanism part to the composite slider which I created a few months ago. The composite construction can be seen in this image:
The back-end of the slider is of elm for hardness and splitting resistance, whereas the frontend is of pine to keep the weight down. The two pieces are joined together with a half lap splice joint, glue and two vertical wooden dowels. This type of joint should work well, as the slider has to endure mostly compressive forces. The slider is slightly wider than previously, which gives it additional strength. The angle of the dovetail has been adjusted to ensure that the female dovetail is not too weak. The fit between the slider and the female dovetail is more accurate than previously.
Here are some pictures of the entire construction:
The parts of the triggering mechanism are partially old and partially new. The claw is still the old one, as is the trigger. The fork is the same, but its tenon had to be replaced at the old one was too short. The fork has been sunk into the elm slightly, just like in the previous slider, to avoid having to replace the claw with a new one.
The handle is the most interesting addition. It is attached to the slider just like before:
However, the handle part is made of steel pipe through which a wooden dowel is pushed:
The steel part is locked against a two-pronged fork in the case, after which the wooden dowel is pushed to the right or removed altogether:
The reason for this movable wooden dowel is safety; if the handle rivet splits the end of the slider, the slider will inevitably start moving forward. This would be really bad as a wide handle would in this case either break my neck or send the whole case (including the field frames) speeding at my face.
With a removable/displaceable handle the worst that can happen (in theory) is that the slider speeds towards the target, plugging out the cones from the spring bundles with it.