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Old 07-15-20 | 07:24 AM
  #23  
Salamandrine
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Joined: Oct 2015
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From: Los Angeles

Bikes: 78 Masi Criterium, 68 PX10, 2016 Mercian King of Mercia, Rivendell Clem Smith Jr

Originally Posted by Doug Fattic
Just to be clear under normal circumstances a properly brazed eyelet holding a rack on a dropout is unlikely to break. However if a bicycle with a loaded rear rear rack falls over and if the rack or load takes the force of the fall, it is a possibility that the brazing gives way. There isn't enough brazing area between the dropout and eyelet to hold with a strong blow. This can be a marketing problem for a builder. All the customer has to say is "I had a braze-on put on by Doug and it broke". They may or may not give context that explains fully why it broke. Even the slightest hint of something breaking can discourage a potential customer.

The solution is a simple one. The braze-on boss holding the strut of a rear rack doesn't have to be on top of the dropout. It can be a water bottle boss brazed into the bottom of the seat stay just above the dropout. It simply will not break off there. Some of my frame building class students have chosen dropouts that they liked that did not have enough eyelets. Their solution was to braze on the boss holding either the fender or rack into the bottom of the fork blade or seat stay. That way it works just fine.
Thanks for the detailed explanation. That does make sense. Your solution sounds like a very good idea.

It occurs to me that in older days, if a bike fell over, the Pletscher rack or maybe Blackburn rack would have bent or broken long before the braze on -- assuming the eyelet is brazed on. With a modern tubular steel rack, the eyelet is much more likely to be the failure point. Also, I suspect people now tend to load bikes more heavily than in the past when bike touring.
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