Dropout retrofit question

[Will Outlaw]

Summary: I acquired an older fuji frame with a broken driveside dropout. Looks like the poor thing just sort of started rusting and the dude who owned it (a buddy of mine who goes 250 pounds, considers 80 rpm to be "spinning" and is strong and fast as hell) finished it off mashing on the way to work one day.

For practice, I decided to fix it by retrofitting a set of stainless track drops.

So, the question is: How the hell do I get the inside of the seat and chainstays down to bare metal where they meet the new track drops? Or, do I even need to?

I've filed the tangs that extend over the plate drops so I'm good there, but there's still some residual brass (at least I assume it's brass) inside the stays that I can't reach with a file but that will surely get filled with silver since I want as much contact area as possible.

Can I just fill the silver over the residual bronze and get a strong join or do I need to go dropout-silver-bare metal at all costs?

Hopefully that explanation makes sense.

I'd love to give the frame back, but only if I'm certain the drops are gonna hold and from what I'm seeing, I need to get as much surface area as possible joined with silver to be certain.

Another option I considered was to switch to mild steel drops instead and use brass, but I think the same "how clean is clean?" question would still apply.

Any advise is much appreciated, and yes, I'm a novice with two whole frames under my belt so this is uncharted territory. :-)

[afwalker]

I did kind of the same thing, old Lemond 853 put stainless steel dropouts for the repair of the beyond fixing drive side dropout. I couldn't get the old drops to heat loose so I used longer dropouts in the cut ends. Maybe 853 when reheated gets so brittle I didnt seem to have any other choice. Anywho, Filet pro and SS drops, got it rideable.
Replaced broken dropouts on Lemond 853 by afwalker, on Flickr
Waiting to hear answers to your question, I've only 4 bikes made so I'm just a newb.
cheers
andy walker

[Andrew R Stewart]

If this is your first/second/third.. try at brazing consider not using SS. It has a different heat take up and color change along with a need for good prep. Wthout practice it can result in a braze that will be problemitic later.

cleaning the inside of the stays is simply running a file/sand paper/dremel up inside. Of course the smaller the stay's diameter the smaller the device. Ideally when removing the drop out bits care had been taken to shake out the brass that's left inside. Don't worry about using Silver oner brass as long as all is clean. The two get along well. Silver and grime don't. If you're unsure about the cleaning then don't use SS and do use brass. Andy.

[Curt Goodrich]

For future reference: When melting out the drop out, be sure to heat the well away from the stay and flow the filler material way out onto the drop out. While this won't completely eliminate the need to clean up the inside of the stay, it will reduce the amount of work. The same technique is applicable to replacing a tube in a lugged frame. Whatever is being replaced (drop out, tube) is garbage anyway, don't worry about heating it up. Work smart.

[Will Outlaw]

Thanks! I was most worried about silver/brass and how they'd fare together. Sounds like they'll be happy.

Getting the grime out is simple enough but that leftover brass (there wasn't a lot, but enough that it raised the question) sure is tenacious. :-)

[Sixren]

Cut the drop out to be removed in two pieces.
It´s so much easier to heat and remove one joint at a time.

[Eric Estlund]

With your Fuji I don't think it will be an issue, but pay attention to how the drop out locates the axle. If it is to far out of the stays center line (up or down) it may limit your options for a 1:1 replacement. Keep an eye (or at least plan around) how changes at the drop out end can influence not only rear center, but seat/ head tube angles, BB drop and brake bridge (relative) position.

[afwalker]

Cut the drop out to be removed in two pieces.
It´s so much easier to heat and remove one joint at a time.

Interesting, how would one cut the dropout? Just up to the stay?
thanks
andy walker

[Andrew R Stewart]

You cut the drop out in one or two slices that will allow one part (and therefore the tab in the stay) to pull straight out without interference with the other section of the drop out. Then remove the second part/section. Andy.

[Will Outlaw]

With your Fuji I don't think it will be an issue, but pay attention to how the drop out locates the axle. If it is to far out of the stays center line (up or down) it may limit your options for a 1:1 replacement. Keep an eye (or at least plan around) how changes at the drop out end can influence not only rear center, but seat/ head tube angles, BB drop and brake bridge (relative) position.

I was actually pretty worried about that. The track drops locate the rear axle slightly higher than old campy/Columbus semi-horizontals. I placed them as low as possible so the "middle" wheel position of the new drops very close to where the "middle" of the old drops would have placed the wheel.

I also checked the position of the brakes (cantis) with a true rear wheel and it looks good. At the most adverse wheel position the cantis are just at the upper limit of adjustment so it should be fine.

Using a true rear wheel really helped me get the positioning and alignment sorted. It was tougher than I expected since a tiny misalignment in one wheel position is magnified hugely the other end of the drop.

Interestingly, I never gave much thought to the challenges of getting horizontal drops aligned and positioned correctly. They're tricky little bastards. I also have a new appreciation for the genius behind the semi-horizontal dropout design.

If nothing else, I've learnedly a ton through this process, which is all I can ask.

[Will Outlaw]

You cut the drop out in one or two slices that will allow one part (and therefore the tab in the stay) to pull straight out without interference with the other section of the drop out. Then remove the second part/section. Andy.

After some head scratching that's exactly what I did on the unbroken side. Made life super easy.

There was a surprising amount of tension released when I cut the good drop which had me wondering at how well the thing was aligned initially. Things down there should be nice and stress free when I finish up.

[Dave Anderson]

You cut the drop out in one or two slices that will allow one part (and therefore the tab in the stay) to pull straight out without interference with the other section of the drop out. Then remove the second part/section. Andy.

+1..... This is what I call the "Paterek" method (because that's who I learned it from). It works very well. In addition to cutting the drop out, clamp a large vice grip to the piece being removed and let is all hang down vertically. Put all of the heat on the drop out piece and the weight of the vice grip will pull it out when its all hot enough. A final step, immediately after the drop out piece pulls out, is to rap the stay with a hammer or etc and the hot brass will fall out. This leaves a nice clean hole with minimal clean up. It even works great with domed stays....saving the domes (see below), etc.

The beauty of the vice grip trick is that it helps prevent damage to the stays.....because when trying to pull drops out by hand, many people have a tendency to pull too soon or with too much pressure and before the area is uniformly hot enough (especially if they are brass brazed)...and many a bent or stretched or torn stay has been the result, etc.

Dave

[Andrew R Stewart]

Dave- What prep did you do with the chrome on the pictured repair? Andy.

[Dave Anderson]

Dave- What prep did you do with the chrome on the pictured repair? Andy.

Hi Andy,

I am not exactly sure what you are asking.....Do you mean prior to putting that paint on?

Dave

[Andrew R Stewart]

dave- No, prior to brazing. Did you sand/grind off the chrome or just sand clean as bare steel usually is? Andy.

[Dave Anderson]

Once I heated and removed the old drop out (with good ventilation and with wet rags mitigating heat migration), I just abrasive blasted the tips, making sure that I got the inside of the stays and slots good and clean....wiped with acetone....and then fluxed and brass brazed, etc. I wicked the brass into the joint, just as they were originally brazed, in order to maintain the domes and the original look, etc. About an inch of chrome was lost on each stay.

Dave

[Will Outlaw]

As always, the amount of knowledge present here, and the willingness to share it, is wonderful.

Next time I'll ask the question BEFORE I light the torch. :-)

[duanedr]

Once I heated and removed the old drop out (with good ventilation and with wet rags mitigating heat migration), I just abrasive blasted the tips,

Thread resurrection!

So, would I get the right effect using sandpaper or should I take a file to it and try to get down to the base metal?

By the way Dave, I was looking through your flickr photos and was just amazed. Beautiful bikes.

Thanks

[Dave Anderson]

Thread resurrection!

So, would I get the right effect using sandpaper or should I take a file to it and try to get down to the base metal?

By the way Dave, I was looking through your flickr photos and was just amazed. Beautiful bikes.

Thanks

Thanks! Do you mean for prepping the inside of the stays before brazing? If so, all you really need to do is shine it up in there so that the new brass will wet to it. You don't have to get down to bare steel. Bare brass will do as well. A small file, or a cutter bit or etc. on the end of a Dremel would work, etc.

Dave

[duanedr]

I'm more thinking about the chrome on the outside. Or does that not matter? I suppose very little adhesion happens there but, just wondering if the underlying copper melts and causes problems or??! I'm an accountant, not a metallurgist.