working with old pressed seat lugs - reinforceing for seat binder bolt

[rstankus]

My first post here so I hope this works! I am doing some practice brazing as it's been a few years since building a frame. I am reinforcing the ears on a seat lug using a brazed in steel tube that will be brass brazed into the ears. Some of the old pressed lugs I have a full tube surrounding the seat tube as part of the lug - but many of the lugs I have are just bulged out in that area to create the ears. What is the correct method reinforcing this area when the lug does not provide a complete surround for the seat tube. I am thinking that I would start by brazing in the tube with brass from the outside/rear of the lug and then flip it around and fill in more brass from the inside of the lug. Apologies is this has been covered earlier - but I searched and was unable to find anything. Thanks for any guidance.

Roman Stankus

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[Andrew R Stewart]

Hello Roman- The supporting of a pressed seat lug binder ears is a good thing, I shake my head at all the hand built frames (be they production or custom) that haven't done this, and the binder bolt is doing "a job" on the ears. I've done both filling the lug ears with only brass and adding a steel sleeve. The sleeved method was easier to braze up and usually has less grinding away at the ID right at the ears to fit over the tube. I have done a shallow miter on the support tube's face that would contact the seat tube to further reduce the after brazing clean and prep.

I recently (as in my meager production) made a frame with pressed lugs and did the sleeved support method. IIRC I used the same initial brazing sequence before "how it's going" took over:) Andy

[e-RICHIE]

fill it with brass. file away any and all that doesn’t make your eyes happy. drill with a 5/16” bit. and later run a counterbore through each side to ensure a bolt will seat nicely.

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