Seatstay attachments continued...

[suhacycles]

Hey fellas,

I was thinking of trying the classic side-mounted seatstay attachment for the first time and wanted to hear some thoughts on how to approach it. I was considering one of two ways to increase the surface area: 1) File the plug and seat lug surface flat or 2) Keep the plug rounded (or no plug at all) and try to file a matching curved surface into the seat lug. Any tips or warnings would be great.

Thanks!
Hansen

[e-RICHIE]

both methods work atmo.
i always braze the assembly horizontally so that no jizz or heat travels down the seat tube.

[Tom Kellogg]

OK, here we go.

We miter into the seat lug, generally in line with the line of the seat tube/top tube miter. We have a jig that holds a Foredom grinder in line with the seat stay tab on the rear dropout. That way, the miter is perfectly in line with the stay itself and the contact area between the seat lug and seat stay is quite large. In any case, we do NOT miter the stay itself. It would look the same when done, but the contact area is WAY less. Filing the lug and cap flat causes their its own problems; how to perfectly match the surfaces, etc? You will notice that we don't use plugs but miter in and braze on caps. Hope this helps.

ST_Miter1.jpg
The miter. Note the little scribe marks indicating to Jeff where he will be ending the stay itself and where the centerline is.

ST_Miter3.jpg
The stay in place but not soldered up. Because Jeff leaves the stay end up away from the lug a bit, it helps keep the detail sharp after paint and it also makes the stay attachment look less heavy, more like it is floating above the lug.

ST_Miter2.jpg
Another angle, again looking "light."

ST_Miter4.jpg
And finally from the rear. This one really shows how much we leave the stay trimmed beyond where it leaves the lug. Once the fillet is in there, it looks just right.

[suhacycles]

Thanks gentlemen. That's some purty stuff Mr. Kellogg. I didn't know you could file/grind a groove that deep but I guess there's plenty of metal left without compromising the seat tube. Would there be any reservations with creating a larger groove that fits a larger sized seatstay, say a 17 or 19mm?

-Hansen

[pereiracycles]

I'm working on my version of the Kellog setup. I only have the wimpy "jacobs chuck" foredom handle, and I only have the cartridge rolls to work with, but the collet handle is on order. Planning to use carbide burrs. Tom, what do you use for cutters? This worked well for me. I didn't go to deep, but it's already better than trying to line it up freehand.

[e-RICHIE]

i used to channel out the lug similarly and during that period, i had a pair of extra long surrogate seatstays that would fit
into the dropout tabs. i'd square up the stays, position them on the lug where i was happy with the intersect, and then
scribe the groove-to-be with a lead pencil atmo. remove surrogate(s). find a 10" rat tail. show the lug who's boss atmo.

http://www.flickr.com/photos/9866331...944755/detail/

[Tom Kellogg]

... Tom, what do you use for cutters? ...

We use the continuous duty handles and diamond cut carbide burrs. Single cut burrs just make little splinters that get stuck in your hands. The continuous duty handles not only hold up better, but they cut without chatter as well. Jeff will spend maybe 20 second on each miter but the setup time makes the whole process take all of about five minutes ... and it is perfect. K?

[Zimmermanbicycle]

+1 on Tom's method but I do it with a file sighting in line with the dropout after marking the seatstay position, simple, fast and plenty of surface area.
-Eric Z

[suhacycles]

i used to channel out the lug similarly and during that period, i had a pair of extra long surrogate seatstays that would fit
into the dropout tabs. i'd square up the stays, position them on the lug where i was happy with the intersect, and then
scribe the groove-to-be with a lead pencil atmo. remove surrogate(s). find a 10" rat tail. show the lug who's boss atmo.

http://www.flickr.com/photos/9866331...944755/detail/

Thanks for the link. I'm curious, you said you used to channel the lug. What about now and why the change if I may ask?

[e-RICHIE]

Thanks for the link. I'm curious, you said you used to channel the lug. What about now and why the change if I may ask?

i double miter the seat stay top and am happier with this method atmo -

[suhacycles]

i double miter the seat stay top and am happier with this method atmo -

Gotcha... looks like plenty of surface area. Thanks!