Frames seem to be easy enough to make; easy enough that spending $25+ for a prebuilt frame doesn’t make much sense to me. I’ve seen a number of DIY frames on RCG, and while they can be built fancy and expensive with carbon fiber and the like, many people make them out of aluminum and/or wood, PVC, etc. Many frames are constructed with the arms in an X, and usually sandwiched between two squares of material to hold them. This also provides a platform for the electronics and battery. Here’s an example I found with a quick Google search: (Click to go to his Flickr page for a description)
The L-brackets at the ends of the arms appear to be blade guards, and are the first time I’ve seen a blade guard like that. Most don’t have blade guards, and mine probably won’t either. As long as you keep it at a safe distance you don’t have to worry about it. Note that he does have a “sandwich” of two plates, the one on the bottom is just smaller.
This is what I came up with last night, using Google Sketchup:
The plate is 6″ square, and the arms extend about 6″ outwards from the corners and are 0.75″ square. They most definitely might vary on the final design, or after testing, but they seemed reasonable. I plan on using a sheet of aluminum and wood arms, mainly because I have some scrap pieces of sheet aluminum and wood is cheap. I’m not sure yet what I’ll use for landing gear, but I was thinking that if I go with wood arms I will just use a short vertical piece of the same size wood on the ends of the arms. Many people use helicopter landing gear, as the person in the example picture did, which has the benefit of a neat, clean look and doesn’t weigh much. Gear with a wider footprint is desirable for a beginner in RC helicopters, and so I will use the same reasoning for my quad. Quads, after all, are nothing but a helicopter with four blades instead of two.
I did not mention in my first post, but there are two additional things that I ordered for the quad already.
- A flight control board (FCB). This is the brains of the quad. I bought the Naze32, available from AbuseMark.
- A prop balancer. I bought a Top-Flight TOPQ5700. This model holds the propeller vertically on a horizontal shaft which itself is held up by two magnets, giving a very low friction shaft, allowing the heavy side to be determined so that the propeller does not cause vibration while in spinning.
It’s going to be around two weeks, at least, before I get my order from China. I plan to continue working on this frame, so I can fly sooner once the order finally comes in. Also, I am partially completed in the conversion of my transmitter from 72 MHz to 2.4 GHz, and I will cover the conversion as well when that is completed.