Bicycles are great. They make moving about much more efficient and fast than walking, without having to worry about fuel, tax, insurance, parking etc etc. But if you need to take some stuff with you it gets more difficult. Cargo bikes come in two basic types; ones where you put all the stuff behind you, and ones where you put all the stuff in front of you.
Putting stuff in front of you seems better to me. You can keep an eye on it and it seems like a more efficient use of space. Putting the cargo behind you means extending the chain and keeping things clear of the space your feet need to pedal in.
Since I mainly wanted this bike to carry my two daughters I really wanted them to be in front of me where we can talk more easily and they have a good view.
Bikes with extended front ends are commonly called "Long Johns" and although they can seem more difficult to make at first, with the need for a steering linkage and an extra headtube, it really isn't that difficult to make one.
I dont know if this is a new way to make a Long John I made it up as I went along and it removes the need to have much in the way of jigs etc. I have a lathe and a pillar drill so I made the most of them, but with a bit of imagination you could manage without and do this whole thing with just a hand drill, a hacksaw, a file and some patience.
Even if you dont want to make a Long John I hope that you enjoy reading this instructable and it gives you some inspiration to do something else in the same way that I was inspired to write my instructables by reading other peoples'.
If you do decide to build something then make sure you stay safe, be careful with tools and don't ride any kind of bike unless you know it is safe.
Step 1: Find a donor bike
If you are some kind of fanatic you may want to build the entire thing from scratch, but it is a lot of extra work when you can easily find a donor bike to give you all the "difficult bits" ready made.
I didn't have to look far for a donor bike as I had this old mountain bike cluttering up the cellar. This is/was actually my wife's bike, but she hasnt ridden it in years and really deserves a new bike. It had also had a pretty rough life so the front triangle wasnt up to much anyway, so it was perfect for this project. It forced me to build in Aluminium which was fine by me because I wanted to keep the weight under control and it is easy to work with (aside from the welding). This frame is 7005 aluminium which means you need slightly different welding rods, but this isnt a huge hassle.
It is important to bear in mind that welding an aluminium frame will mess up the temper of the aluminium, but some of this strength will be regained with age hardening over time and we are going to be fairly heavily over engineering this thing anyway.