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Otto Rax 03-11-14 07:35 PM

How to deconstruct a brazed frame?
This may seem counter productive, but let me explain.

I collect dropouts, and many of the ones I'd like to display are seemingly unavailable or prohibitively expensive to find as JUST the dropouts. There are a few that I have on damaged frames that I'd like to remove and mount in the collection, but alas they are still part of a frame.

I understand it would be easier to remove from a silver-soldered frame versus bronze, right?

With either, is it just a matter of heating the joint and working the dropout out?

Does it have to get cherry red with an oxyacetylene setup?

Once it's been removed, how can I clean the residual bronze or silver off of the dropout?

How far off are the melting points compared to the steel? I don't want to destroy the dropout in the process either.

Any hints, tips, tricks, or other information is much appreciated. Or, if anyone has any random Driveside dropouts they want to sell, let me know. This is the beginning of the collection, as I only have 9 so far.

That's for the deconstruction wisdom

repechage 03-11-14 09:15 PM

Having removed dropouts for a repair... where you want to save the adjacent tubes...
It takes a surprising amount of heat, rosebud tip helps.
The trick is getting the whole joint hot to get enough of the brass (almost always brass) to flow again at the same time.

I should add that when I was taking things apart, the dropout was overheated as it was waste.

If you have a damaged frame that will not be rebuilt then you could with a hack saw and file get the job done.

You will have some joint material to mechanically clean up, both brass and silver "wet out" and fill the exterior grain of the steel.
That is what helped make the joint strong enough to begin with.

Beware of pins. You will be surprised how many frames have them one one or both of the stays.
So strip all the paint off first should you go with heat to harvest.

tuz 03-12-14 08:14 AM

Yes you can cut the stays near the dropout and file them out, or you can heat them (use flux) and pull them out. You can also use a brush to remove the remaining brass while heating, and then file/sand the rest. You need to get the metal red hot, it's still far from the melting point of steel. Use a large tip.

fietsbob 03-12-14 10:40 AM

You cannibalizing just damaged frames ?

Otto Rax 03-12-14 05:21 PM


Originally Posted by fietsbob (Post 16571043)
You cannibalizing just damaged frames ?

At this point yes. I don't want to destroy good frames

fietsbob 03-12-14 05:49 PM

Glad to hear that .. I was wondering ..

unterhausen 03-12-14 06:07 PM

attach a pair of vice grips to the dropout, point it down, and heat the tube to within an inch of its life. the dropout will fall out eventually, they don't even have to get that hot. Getting mild steel dropouts hot doesn't really hurt them much.

I replaced some dropouts that I wanted to save, but I wanted to save the frame more. I reversed this process. The stays didn't need to get that hot before the dropout let loose. I pulled the chainstay side first, and then the seatstay. This is because the seat stays will bend the 1/2" they need to bend.

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