adding "braze-ons" to an aluminum frame

you can try some clamp-on downtbe shifter bosses....campy and suntour used to make them.
check ebay...

"john hood" <[email hidden]> wrote in message
"]news:[email hidden]...

Quoted message said:

I've got a Debernardi road frame, constructed of Altec2 tubing. This frame has the obnoxious
feature of "downtube" cable stops on the headtube, which causes the derailleur cable housings to
get mangled by the front brake all the time. I'm tired of having a bike that doesn't shift because
of this.

It occurs to me that maybe I could attach more conventional cable stops or lever bosses to the
downtube and grind/file away the originals, but obviously welding new ones is Right Out. So what
are my options? I can think of epoxying bosses on, or possibly a bolt-through type of lever boss
such as Cannondale used for many years. What's likely to hold up and not weaken the frame greatly?
And are there framebuilders or other out there who will do this sort of work?

--jh

--
Mr. Belliveau said, "the difference was the wise, John Hood,

cgull

Quoted message said:

intelligent look on the face of the cow." He was

+usenet@

Quoted message said:

*so* right. --Ofer Inbar

glup.org

Tektro makes a clamp on up to 1 3/8". For larger I have used a rivet/epoxy stop purchased from
Linear recumbents. tom

--
Bruni Bicycles "Where art meets science" brunibicycles.com
410.426.3420 serg <[email hidden]> wrote in message
"]news:[email hidden]...

Quoted message said:

you can try some clamp-on downtbe shifter bosses....campy and suntour used to make them.
check ebay...

"john hood" <[email hidden]> wrote in message
"]news:[email hidden]...

Quoted message said:

I've got a Debernardi road frame, constructed of Altec2 tubing. This frame has the obnoxious
feature of "downtube" cable stops on the headtube, which causes the derailleur cable housings to
get mangled by the front brake all the time. I'm tired of having a bike that doesn't shift
because of this.

It occurs to me that maybe I could attach more conventional cable stops or lever bosses to the
downtube and grind/file away the originals, but obviously welding new ones is Right Out. So what
are my options? I can think of epoxying bosses on, or possibly a bolt-through type of lever boss
such as Cannondale used for many years. What's likely to hold up and not weaken the frame
greatly? And are there framebuilders or other out there who will do this sort of work?

--jh

--
Mr. Belliveau said, "the difference was the wise, John Hood,

cgull

Quoted message said:

intelligent look on the face of the cow." He was

+usenet@

Quoted message said:

*so* right. --Ofer Inbar

glup.org

In article said:

you can try some clamp-on downtbe shifter bosses....campy and suntour used to make them.
check ebay...

Nope, like most aluminum frames these days, the down tube isn't round, it's teardrop shaped. I
suppose one could bend a steel one to fit, but getting one the right size might be tricky, and the
tubing might not tolerate the clamping stress well-- anyone know?

--jh

--
Mr. Belliveau said, "the difference was the wise, John Hood, cgull intelligent look on the face of
the cow." He was +usenet@ *so* right. --Ofer Inbar glup.org

(john hood) said:

I've got a Debernardi road frame, constructed of Altec2 tubing.

...

Quoted message said:

It occurs to me that maybe I could attach more conventional cable stops or lever bosses to the
downtube and grind/file away the originals, but obviously welding new ones is Right Out. So what
are my options?

Welding new ones is definitely not "right out", but it's kind of a production. Altec2 is 7005
aluminum; it's very weldable and it heat-treats itself at air-cooling rates. (That is why it's used;
it is no better than 6061 alloy in other respects.) The second part of aluminum heat treating is
"aging", which can be done in a few hours with an oven or in a few weeks by just letting the thing
sit around.

The obvious drawback to welding stops is the effect on the bike's paint. Since I am contemptuous of
paint on aluminum bikes, I actually like it to be removed or at least defaced. Since you bought an
eye-talian frame I presume you feel differently about such things.

You could pop rivet cable stops onto your frame. A resourceful LBS can find rivetable stops for you,
and might even be willing to rivet them on for you.

The most important thing to remember when drilling holes in your frame, as when riveting, is to
locate the holes in regions of lowest possible local stress. The bike shop will know these areas as
places they have never, ever seen a frame break or bend. The end of the down tube close to the head
tube is actually not a good place to add a stress riser. The reason that downtube shifters are
located where they are is because that's about as far up as you can go and not cause problems.
Sometimes they cause frames to break at that point anyway, so take heed.

Chalo Colina

[email hidden] (john hood) wrote in message
news:<[email hidden]>...

Quoted message said:

I've got a Debernardi road frame, constructed of Altec2 tubing. This frame has the obnoxious
feature of "downtube" cable stops on the headtube, which causes the derailleur cable housings to
get mangled by the front brake all the time. I'm tired of having a bike that doesn't shift because
of this.

so stupid, right? i just built up a bianchi with this problem. looks like it was designed for campy
only, as the longer arms on the campy calipers would provide a little more breathing room b/w
cables. still, dumbest thing ive seen on an expensive frame. when you turn the hbar left and right
"click.. click" as the cables push against each other and release, and it bends the cables at
terrible angles. im guessing two weeks and itll be permanently crimped at the stop.

Quoted message said:

It occurs to me that maybe I could attach more conventional cable stops or lever bosses to the
downtube and grind/file away the originals, but obviously welding new ones is Right Out. So what
are my options? I can think of epoxying bosses on, or possibly a bolt-through type of lever boss
such as Cannondale used for many years. What's likely to hold up and not weaken the frame greatly?
And are there framebuilders or other out there who will do this sort of work?

are you handy? do you mind mickey-mousing it? im new to hte bike world, so maybe there is a clean
elegant solution, but if you cant find something off the shelf which will work, i would venture to
guess you could improvise some cable stops. all they have to do is stay in one place.

the clean solution: i definitely think epoxying them would work. in fact, the place i work at had
some NOS 'braze ons' that sound perfect for you. if my guess is right, they were the glue-on
downtube shifter braze-ons for carbon/Al-lugged frames that trek/specialized made a while back. they
have a backling plate, precurved to the shape of a DT with lots of surface area. you could fire up
some quality epoxy, glue these on, and then just screw in the commonly available downtube shifter
--> STI cable stop adapters. heck, itd look good, and youd have barrel adjusters and everything!
maybe you could find them at a trek dealer, call trek and ask, or troll r.b.marketplace.

the mickey-mouse: if it were my bike and i didnt happen to have the bits and pieces, id probably buy
two cable stops from a framebuilding braze-on place. lots of those online, and i think even QBP
stocks a bunch so your LBS coudl prob order. then make a band of metal to clamp around your DT.
something like the stock LBSs have lying around for attaching rear racks, or a bit of steel from
your hardware store. bend it around your dt, with a bit of rubber shim underneath to protect the
paint, or a slice of old inner tube. or duct tape, on the metal might be stiffer. bend the ends up
with a gap between them, and drill holes for a bolt and locknut. mark where you want the stops. and
braze or solder them on with whatever is about. propane torch. plumbers solder. something like that.
spray paint it. i think it could look pretty decent. in a pinch you might use housing cable ends
instead of real cable stops, or make 'em in shop class.

anthony

[email hidden] (Chalo) wrote in message
news:<[email hidden]>...

Quoted message said:

(john hood) said:

I've got a Debernardi road frame, constructed of Altec2 tubing.

...

Quoted message said:

It occurs to me that maybe I could attach more conventional cable stops or lever bosses to the
downtube and grind/file away the originals, but obviously welding new ones is Right Out. So what
are my options?

<snip>

Quoted message said:

You could pop rivet cable stops onto your frame. A resourceful LBS can find rivetable stops for
you, and might even be willing to rivet them on for you.

The most important thing to remember when drilling holes in your frame, as when riveting, is to
locate the holes in regions of lowest possible local stress. The bike shop will know these areas
as places they have never, ever seen a frame break or bend. The end of the down tube close to the
head tube is actually not a good place to add a stress riser. The reason that downtube shifters
are located where they are is because that's about as far up as you can go and not cause problems.
Sometimes they cause frames to break at that point anyway, so take heed.

Chalo Colina

An entirely do-able scenario: find someone who can install a pair of Rivnuts (
eaa.org.zarivnut.phpOpen ↗ ) on the downtube. Occasionally a bike shop will have
these and the tool that installs them- it's an easy way to add water-bottle mounts without torching
a frame. A pair of these on the sides of the downtube and you'll be able to screw on a pair of
Shimano cable stops: harriscyclery.netpage.cfmOpen ↗ You'll want the
stops with the curved backs instead of the flat-back units.

Jeff

(john hood) said:

I've got a Debernardi road frame, constructed of Altec2 tubing. This frame has the obnoxious
feature of "downtube" cable stops on the headtube, which causes the derailleur cable housings to
get mangled by the front brake all the time. I'm tired of having a bike that doesn't shift
because of this.

It occurs to me that maybe I could attach more conventional cable stops or lever bosses to the
downtube and grind/file away the originals, but obviously welding new ones is Right Out. So what
are my options? I can think of epoxying bosses on, or possibly a bolt-through type of lever boss
such as Cannondale used for many years. What's likely to hold up and not weaken the frame greatly?
And are there framebuilders or other out there who will do this sort of work?

--jh

framebuilding.comAluminum Aluminium Alloy Titanium.htmOpen ↗ Art. 298 or similar

[email hidden] (john hood) wrote in message
news:<[email hidden]>...

Quoted message said:

In article said:

you can try some clamp-on downtbe shifter bosses....campy and suntour used to make them. check
ebay...

Nope, like most aluminum frames these days, the down tube isn't round, it's teardrop shaped. I
suppose one could bend a steel one to fit, but getting one the right size might be tricky, and the
tubing might not tolerate the clamping stress well-- anyone know?

--jh

Highly improbable. Clamp-on on downtube shifters were only built for 1 1/8" round tubes. I really
doubt you'll find a clamp to fit your downtube. Rivnuts may be your only solution.

Jeff