This is a simple example where I've used some strong and light aluminium tubes. Yes, the joints are also 3D printed but it would be quite easy to make them out of wood or simply join the tubes together and put a wood board between them. Check the next fotos and see how easy is to build a drone frame like this one. Is light and strong.
You could fix the brushless motors directly to the tubes if you don't have the 3D printed pads. Use some zip ties to fix them in place. As you can see in the photos, the flight controller is made out of an Arduino mini and 3 modules, accelerometer and gyro, barometer and magnetometer.
In the next photos I show a few examples of wood frame for our drone that I've found on the internet. In the fourth photo we can see the easiest design that we could build. It is very practical. Always use light and strong high quality wood. To join the parts try always to use light aluminium screws. Any thing to make the body lighter because once we put on it the battery, motors, ESCs and all the electronics, it will weight a lot.
You could fix the brushless motors directly to the wood with screws. Use some zip ties to fix them in place if you think the screws are too heavy. As you can see in the photos, the flight controller must me as centered it could be.
In the next photos I show a few examples of PVC tubes frame for our drone that I've found on the internet. In the fourth photo we can see the easiest design that we could build. It is very practical. Using PVC tubes we can easily pas the wires through the tubes without having a drone full of wires.
PVC is a very strong, elastic and light material. You can also buy it with the PCV joints and use PVC glue to build the frame.