Chronicles from the deep end: Cargo bike

It was hard, spent 150$ for a ten 56 rods and i went to town with the Mapp torch, it’s hard to control that thing with such a wide flame!

Anyhow, it’s done, it’s straight and after filing should be ok looking!

Now i need a cup to weld onto the 35mm tube to hold the headset, i have one but i need two, anyone knows if i can find it off-the-shelf?

This is what i have:



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Alright, I have filed down some of my fillets and I am having a huge doubt, because I am impatient, I have used 56% silver rods to braze the BB and top-tube to the front of the cargo, see pictures.


My question is:

  1. Will 56 Silver hold without a lug?
  2. How big of a braze do I have to make? I know I have to go back and add more…
  3. Can I switch to Nickel-bronze or Nickel-Silver to add more? Or will I risk to melt the 56% base?
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I wouldn’t use 56% silver in this application. Unfortunately it has a low melting point so you can’t easily do another pass with a different material over it.

To figure it out for yourself you could take two pieces of scrap tubing, miter and do the same kind of fillet. Then test to destruction to see if the tubing fails (good) or the silver fails (bad).

56% silver is also very expensive. I would save it for the tight clearance lugs on future projects.

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Replaced the silver…

It’s very hard to juggle the huge cargo frame while brazing but I believe I did ok.

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The paint process has started, using all the leftovers from other paint projects, I blued the whole frame and then “splotched” it, this frame will see more development in the future so I am going to keep it “raw”

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:expressionless:

I guess I should have checked the alignment before painting…

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Alright, found out that i bent my own headtube when brazing it. It was stupid of me.

Any idea on how to best straighten it out? Maybe heat?

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I did this when brazing the head tube on my cargo bike aswell. I posted about how I used flame straightening to realign it. I haven’t tried reaming the headset yet but it seemed to work really well
I’m not sure how to link another thread but it’s in my cargo bike thread

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