Data concerning silver joint strength vs. fillet width.

[Adam Eldridge]

https://www.lucasmilhaupt.com/en-US/...icalbulletins/

The more I read the more I understand the "pretty" wide fillets (including mine) that most builders employ are in fact rubbish, weak and a complete waste of material.

Time to mix it up.

[echelon_john]

Was there a specific doc/reference? I just looked through the PDFs and didn't see specifically what you were referring to, but would love to see it.

Thanks,
John

[Adam Eldridge]

John,

Also search for Keith Bontragers non scientific material. He compiled data in excel which was plotted by Bob Brown here: Bob Brown Cycles: analysis

There is data in the PDF's, it's dry but if you read the PDF's it's in there. The majority of the data revolves 360 degree tolerances of .005 between ones miters.

[Chauncey Matthews]

Talking about brass here:
It's easy to make a tiny little fillet that can be stronger than the tube in a "braze it and break it" test, but that doesn't tell you anything about the long term durability of the join. I think fillets should be a moderate size so that you can make nice smooth transitions and spread out the stresses.

[prolix21]

Talking about brass here:
It's easy to make a tiny little fillet that can be stronger than the tube in a "braze it and break it" test, but that doesn't tell you anything about the long term durability of the join. I think fillets should be a moderate size so that you can make nice smooth transitions and spread out the stresses.

I would tend to agree with this, as it lines up with the functionality of a lugged joint. More contact between joining material (lug, fillet) = a less focused point of stress. I'm no engineer though, just makes sense to me.

[edoz]

Talking about brass here:
It's easy to make a tiny little fillet that can be stronger than the tube in a "braze it and break it" test, but that doesn't tell you anything about the long term durability of the join. I think fillets should be a moderate size so that you can make nice smooth transitions and spread out the stresses.

I'm in this camp as well. I think even crappy brazed joints are often strong enough, so after it's functionally satisfactory you start looking at aesthetics and you lay down the fillet that you think looks good. Look at some of the monster fillets on Ritcheys, Mountain Goats and others of the period and then consider that those frames didn't typically break at the joints.