So following on from my previous thread on building a cargo bike I have managed to find someone with a TIG welder and has experience brazing as well who is willing to help.

He doesn’t however know much about bikes so there are a few details I need to work out. Im planning on building a replica of the Omnium cargo bike so I will need to buy tubing to build the front end. Im using an old cyclocross frame as the donor for the rear end and a bmx fork.

Im going to need tubing for the long downtube from the BB through to the headset. Im guessing that I would need around a 50mm diameter tubing at 1mm thickness for this.

Can any framebuilders tell me what diameter tubing would i need for a straight headtube with what kind of thickness? I just want a standard 1 1/8 steerer tube to connect the linkage to the front wheel and I think that I would need to be around 1.6mm wall thickness?

Im planning to do updates on here with the progress of the build if anyone is interested and could use the information to build their own.

Thanks!

Ask Reynolds for their tube list.

http://www.reynoldstechnology.biz/contact-us/united-kingdom/
Reynolds 525 cromoly would be OK for a head tube.
Part No. DC159L : 36.4mm O/D, 1.2mm wall, 600mm long

But Reynolds have a minimum order value.

or ask Ceeway for an equivalent.

http://www.framebuilding.com/Gara.htm
NVRM18
37, L=180, 1.6mm wall
600mm lengths available

Or a more complicated cargo trike
https://www.youtube.com/watch?v=moKRzs7XKZs

or 4 wheels
Tripster

coincidentally, arriving at school today was one of Jr’s classmates in this. Recently completed by his father. It was fantastic, and credit to him, he’d pedalled his boy in from 6 miles away. It was really nicely put together.