Originally Posted by
Ritterview
Eric--
Are carbon tandems manufactured in the same process as shown on for the 1/2 bike this video?
The Cyfac tube joining technique appears to differ from that used by Calfee. There is a different appearance, the Cyvac being less bulbous.
When I visited the Calfee factory, I took photographs of the the joints which had been wrapped, compressed and dremelled into shape. As long as you are here (and assiduously avoiding sales talk

), might you comment on the advantages and disadvantages of differing techniques of carbon tube joining on tandem frames, especially as it relates to the thread topic of relative frame stiffness?

Thanks for the question! I'll avoid outright comparisons to the way others do their stratification because I'm only seeing some specific aspects of the process rather than the whole thing. Plus, we have respect for other builders like this and simply want to lead based on our own examples and skill in crafting framesets for passionate cyclotourists as well as world class racers.
Our carbon manufacting is just like the video that you show. As you can see, it's quite a "clean" process without much extra material added and then removed via sanding or some other approach. We spend A LOT of time cutting and mitering the tubes to ensure a very tight fit from the outset so that we are only adding what is necessary to ensure the proper function and durability of the frame in a very meticulous fashion. We use a carbon stratification process that we transfered over from a supplier to Airbus in France. It varies types of woven carbon fabric as opposed to uni-directional sheets. We feel that the weave offers a stronger, more resilient result. It's very labor intensive but yields a tube junction and frameset that is quite strong, sleek, and perfectly adaptable to custom projects (we can change the carbon layers, orientation, make-up per each project). Additionally, we are unique in using a layer of KEVLAR to ensure durability and additional stiffness. This requires some special products and skill because Kevlar needs to be treated in a different fashion.
I hope this helps!
Thanks,
Eric