Thread: Kirk Frameworks
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Old 01-21-2021, 07:48 PM
d_douglas d_douglas is offline
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Join Date: Nov 2004
Location: Victoria, BC
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Thanks for that explanation. Yes, I am no framebuilder (understatement of my life) but I imagined that the lug design is not where the strength is derived from. When seeing this impossibly delicate pointed lugs, one must assume that theyre there mostly for their beauty and elegance, while the fitting of the tube into the lug socket is where the strength comes from.

Those are just right for being ornate. Those ones that Ive seen of old timey Bayliss frames seem more like artwork than rideable bikes, cool as they are.

So, do you just pack those lugs away and one day some lug-lover will ask for something unusual and you coyly say ' why yes, I have something that might interest you' as you reach into your desk drawer??? That would be fun fo both you and the client when the stars align.


Quote:
Originally Posted by David Kirk View Post
Good question. The short answer is 'no'....and long answer is 'maybe'.

The very small relief I made is so structurally insignificant as to not be there. So the answer in this case is no. On the other hand one could cut the lugs so much that there could be issues. So it's not to say that the lug shape doesn't matter but it really only matters when you take it to extremes.....and these lugs are far from extreme.

It's important to remember that the real core strength with a lugged joint comes from the two tubes meeting each other inside and having the filler flow between the them. This is what holds the tubes together. The lug adds surface area for the filler to attach to and a safety margin and its not the primary structure.

Make sense?

dave
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