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Discussion Starter #1
came up with the idea to build a box swingarm for my 350, designed it, then had it lasercut, there are interlocking tabs on each piece that lock things together for tacking, once things are tacked, it can be welded, and it even looks as though things line up well enough where it could be welded carefully without a jig and stay straight

 

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Looks pretty cool, but what's the design goal? I'm no expert so this is just FWIW, but it doesn't look to me like it will offer either more rigidity or less weight than a stock or braced swingarm.
Longer wheelbase?
I'm impressed with the idea and the work, just don't see an obvious advantage yet...
 

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One way you could increase rigidity and jig it at the same time is if you used internal bulkheads at measured intervals. Think about how a model airplane is built, usually without anything more than a triangle to make sure things are at a 90 degree angle - it is self jigging.
 

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Discussion Starter #6
it's far more rigid than stock, probably more rigid than braced, heavier than stock, but not by all that much, most of the mass is close to the center of rotation anyway, so it won't hurt unsprung mass much. I thought about adding ribs on the inside, but couldn't figure out a good way to weld them and then close up the structure... it's a concept model anyway, so I'm sure things I learned doing this will apply to other future things I build too
 

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I would consider putting some holes in the section between the front of the tire and the pivot ant then weld in some sections of tube to provide rigidity and slightly less mass.
 

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On airplanes the bulkhead would have a tab that fits into a slit, you full weld one side and then when you close it up you weld the tab that sticks through the slit and then grind it down. With inside bracing you could then speed hole one of the faces.
 

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I think it's a very nice idea and seems well engineered,
but honestly I don't like the square shape.
The sheets look very strong to me, before reinforcing I
think we should wait and see how stiff it'll be like this.

Best regards
Sven
 

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quote:Originally posted by kenessex

I would consider putting some holes in the section between the front of the tire and the pivot ant then weld in some sections of tube to provide rigidity and slightly less mass.
Agreed. I'm concerned about that span. You can lighten it and strengthen it with vertical pipe sections welded in. But at some point it will be way over built for a CB350...
 

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Discussion Starter #11
I didn't think about tabbing internal reinforcements... that's a good idea, since I partially tabbed the plates for alignment anyway, it's nothing for a laser cutter to make things like that...

and the big section actually got cut smaller, like a dipshit I designed the thing for a 2" extension, then decided not to do that, but kept half the measurements... this is why I only get one part cut at first...
 
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