View Single Post
Old 02-11-21, 12:20 PM
  #4  
Andrew R Stewart 
Senior Member
 
Andrew R Stewart's Avatar
 
Join Date: Feb 2012
Location: Rochester, NY
Posts: 14,830

Bikes: Stewart S&S coupled sport tourer, Stewart Sunday light, Stewart Commuting, Stewart Touring, Co Motion Tandem, Stewart 3-Spd, Stewart Track, Fuji Finest, Raleigh Pro, Trek Cycle Cross, Mongoose tomac ATB, GT Bravado ATB, JCP Folder

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 2888 Post(s)
Liked 1,134 Times in 803 Posts
Why does the tube end have to be a square cross section? Why won't a fillet brazing of the round ended tube to the square form not be doable? Is there a aesthetic reason? Structural one? Does some not mentioned part have to interface with the tube in a way that the tube needs to be square as it contacts the form?

My first thought was to make a tapered square mandrel that, along with a vise, can be inserted and serve as the shaping tool. I'm unsure if I agree with guy153's tube cracking concerns but that is what fabricating something new is about, discovering what works and what doesn't. One could always anneal the tube if it was found on the practice (you will practice this first, won't you?) that the tube did crack. I do like his alternate method though. Andy
__________________
AndrewRStewart
Andrew R Stewart is offline  
Likes For Andrew R Stewart: