Triangle or Trapezoid-ish?
08-21-20, 09:05 AM
#1
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Triangle or Trapezoid-ish?
I read that "triangles are the most rigid structural object known."
Being that the front of this Kona Dew frame is not technically a triangle, wouldn't it be stronger if the top and down tubes were welded together?
Being that the front of this Kona Dew frame is not technically a triangle, wouldn't it be stronger if the top and down tubes were welded together?
08-21-20, 01:26 PM
#2
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Yes, but....
08-21-20, 02:38 PM
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I miss the days of lugged frames. Those great big stack of quarters welds are beyond my current welding ability so to that end I pay homage. But those are just too big and draw way too much attention away from the bike's lines.
Saw a documentary on building bridges. The bridge designer said anyone can build something strong, the real trick is to build it with a minimum of materials.
To answer your question yes, adding more braces would make it stronger. Using solid metal bars would make it stronger yet. But making it stronger than it needs to be just adds weight.
Saw a documentary on building bridges. The bridge designer said anyone can build something strong, the real trick is to build it with a minimum of materials.
To answer your question yes, adding more braces would make it stronger. Using solid metal bars would make it stronger yet. But making it stronger than it needs to be just adds weight.
Last edited by Pop N Wood; 08-21-20 at 03:13 PM.
08-21-20, 02:49 PM
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Some frames, e.g. BMX, put a gusset between the top tube and down tube, to reinforce that area.
08-21-20, 03:11 PM
#5
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I miss the days of lugged frames. Those great big stack of quarters welds are beyond my current welding ability so to that end I pay homage. But those are just too draw way too much attention away from a bike's lines.
Saw a documentary on building bridges. The bridge designer said anyone can build something strong, the real trick is to build it with a minimum of materials.
To answer your question yes, adding more braces would make it stronger. Using solid metal bars would make it stronger yet. But making it stronger than it needs to be just adds weight.
Saw a documentary on building bridges. The bridge designer said anyone can build something strong, the real trick is to build it with a minimum of materials.
To answer your question yes, adding more braces would make it stronger. Using solid metal bars would make it stronger yet. But making it stronger than it needs to be just adds weight.
08-21-20, 03:18 PM
#6
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Luggless brazing is what was used on my 70's vintage Schwinns. Hopefully Casati uses something lighter tubing than the boiler steel Schwinn used back in the day.
My 80's Cannondale MTB is aluminum and they took the time to fill and smooth the welds.
08-21-20, 03:29 PM
#7
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Man, Casati make some pretty bikes. Had never heard of them, thanks.
Luggless brazing is what was used on my 70's vintage Schwinns. Hopefully Casati uses something lighter tubing than the boiler steel Schwinn used back in the day.
My 80's Cannondale MTB is aluminum and they took the time to fill and smooth the welds.
Luggless brazing is what was used on my 70's vintage Schwinns. Hopefully Casati uses something lighter tubing than the boiler steel Schwinn used back in the day.
My 80's Cannondale MTB is aluminum and they took the time to fill and smooth the welds.
08-22-20, 06:36 AM
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Those boys have some skills.
08-22-20, 06:51 AM
#9
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Yes the triangle itself would be stronger, but at the expense of the head tube. It would have less depth of structure where it connects to the triangle.
08-22-20, 03:11 PM
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Buckminster Fuller. The rest of frame design and strength I have to leave to others more knowledgeable than I am.
08-22-20, 04:00 PM
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If you think that’s bad check out this frame. It doesn’t make a proper triangle in any direction
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