Besiege: How to Create the Catapult Arm

What got me over the hump, making building more fun than tedious, was learning how to make a catapult.  I looked at a few guides for building a catapult and even so it took me a bit of trial and error get it to work.  Once I had a working machine, not only was I able to defeat the laser obelisk but between my catapult and a saw blade vehicle the rest of the first island, Ipsilon, wasn’t that hard.

My guide will just tell you how to create the catapult arm.  I’ll leave the rest of the machine to you.  If you don’t want the effort of making one yourself you can always just go into the Steam workshop and subscribe to download a working one.  (Do you search on catapult, trebuchet, or ballista?)

The first piece is the swivel hinge that goes under the arm.  It is possible to have to side swivels but I have the single swivel underneath.  How high above your initial starting block is important.  If the arm is too low it won’t swing and if it is too high it might not fit in the bounding box.  (I initially used the sandbox to create my catapult which doesn’t have a bounding box and then when I went back into the challenge my creation was too big and I had to rebuild it.)

One small wooden block goes on top of the swivel.  I have three double blocks going back and two double blocks in front.  Some guides have different sizes, you can go a little longer or shorter, but this works for me pretty well.

Two springs in front.  Spring angle doesn’t have to match what I have pictured.  The trick is that you have to go into the spring properties.  Highlight the wrench icon and then click on each spring.

Check “TOGGLE MODE” for each spring.  That causes it to contract on a single button press.  I just keep the default key map to L but you can change it to whatever you want.

Add a basket at the end, load a bomb or a fireball and you are ready to test. (Press L)  Don’t try using a boulder.  The boulders are too heavy and won’t fire.  Maybe a higher strength spring would work.  I just used the default strength.

The metal braces on the side are important.  Without them your arm will wobble and probably fall apart.  The rope winch is completely optional.  It lets me pull the arm back up and might allow me to set the catapult angle though I just let it fly all the way.  You want the rope properties to start unwound.

Other things you can try. Move the hinge forward or back on the arm position. Have multiple springs. Have multiple ropes. It’s your design.