Practice, Practice, Practice or Wax on – Wax off

[Dyon Taylor]

After completing Bike #2, I realized that I wanted to go back and spend some time improving my brazing technique. Overall I was pleased with how the second bike turned out, but knew I wanted to make improvements. In addition, while at UBI, Ron Sutphin and Tony Pereira really stressed developing filing and cutting technique. As such, I decided to put together a series of exercises that would help to develop my filing, cutting, and brazing.

I ended up with a set of exercises resulting in almost 300 individual work-pieces, all of which were hand cut, filed, de-burred, and sanded. All of this turned into just over 150 brazed joints:
o “Brake Bridges” brazed with internal rings of 56% silver – I had some previous issues with bridges pulling away during brazing
o “Lugs’ brazed with 56% silver – I wanted to focus on better shore lines
o “Tabbed Dropouts” brazed with bronze – I’ve had limited experience with bronze
o “Seatstays” brazed with 50% silver – As 50% silver can fill a small gap, I thought it might be a good choice for brazing Seatstays to the Seat Tube Lug
o “Canti Bosses” brazed with bronze – More experience with bronze

While I still have a lot to learn, this was a great experience where I learned quite a bit, and know that my next bikes will be better for it.

If anyone is interested, I posted a number of pictures on Flickr: Brazing Exercises - a set on Flickr 

A few photos are included below.

Thanks for looking.

Work-pieces prepped and ready for brazing
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Brake Bridges
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Lugs
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Dropouts
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Seatstays
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Canti Bosses
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Lots of brazing
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[Luke]

That's pretty damn cool.
Keep it up!
-Luke

[Dornbox]

Sweet mother of practice!

[Kumo Cycles]

Bloody excellent

Did you find yourself more comfortable with flowing the filler and controlling the heat as you progressed?

[edoz]

Good plan, it'll pay off in the long run. I bought 30ft of 4130 for practice before I built my first frame.

[Dyon Taylor]

Bloody excellent

Did you find yourself more comfortable with flowing the filler and controlling the heat as you progressed?

Keith - I did get more comfortable with flowing the filler and heat control as I worked through this. In part because I got much better at "reading the flux." I did these in batches of 5 or 6 joints at a time so I could inspect each batch, see where I needed to focus, and apply that to the next batch.

Thanks!

[timto]

Nicely done! I did a whole pile of less organized practice first too. Let me also practice filing techniques for fillet finishing. Amazing what the repetition does for - as you say - reading flux, and heat, and the impact of a good warmup , or of tacking order... keep at it!

[prolix21]

well done, i'm gong to definitely need to do something similar before i start frame #2

[Andrew R Stewart]

As a hobby builder that has long periods of time between frames I find that practice keeps me perfect (just kidding!) Actually I'll do a bunch of practice brazings every so often. Most are fillet/brass. I have a growing object of stubs of tubing brazed at odd angles. A couple of "students" add their parts as they have time.

"Reading the flux" This is an important point to reinforce. Whatever the lighting in your shop, torch tip size or filler rod the flux condition says a lot. Andy.