Jeremy,
I built one frame using Tange tubing in my life. I did not like it and never touched it again. As a craftsman, I know what I like and like to work with. When something doesn't feel right to me I will not work with it, regardless what anyone else thinks or believes or what the marketing trends are at the time. I can't explain to you how or why that is. But if you were to ask Stradavari why he chose to use a particular piece of wood for a particular instrument, I'm sure he would have said the same thing. Some people just know these things.
I'm sure the bike is still on the road and it was build probably in the late 80's or very early 90's. It isn't so much a matter if it works. It's a matter of wheather you like working WITH it.
BTW, once a tube is bent to the point of causing a wrinkle and then bent back, most any steel will probably eventually fail if in a critical location like the DT at the bottom head lug, which is the joint of greatest stress in a bike frame. The same sitiation on a top tube is most likely not going to fail if the DT is sound.
Brian Baylis
La Mesa, CA
Mr. Freeman/Davidson and anyone else with Prestige experience,
"I straightened and rode it a bit more, and it eventually the .7/.4 Prestige downtube cracked."
Over the years some builders have commented to me about those thin .7 .4 Prestige tubes you mentioned. Most agree they have a super compliant and "springy" ride, but the question that always gets different answers is, how durable is this Prestige tubing over the long haul? Some say they never had a problem with it, I know for instance that John Murphy is a huge fan, others say its prone to cracking more eaily than other types. Any thoughts/experiences on this? Thank You Jeremy Lieberman New York City, NY USA
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> CR
>
> Today's Topics:
>
> 1. Re: Ed Litton's cambio corsa bike (Joe Starck)
> 2. Re: More about Silver vs Brass
> 3. Saddle disassembly & riveting redux (Amir Avitzur)
> 4. "Blue Bianchi" (Jack Gabus)
> 5. Re: More about Silver vs Brass (Kurt Sperry)
>
>
> ----------------------------------------------------------------------
>
> Date: Tue, 27 Sep 2005 11:28:51 -0700 (PDT)
> From: Joe Starck <josephbstarck@yahoo.com>
> To: classicrendezvous@bikelist.org
> Cc: themaaslands@comcast.net
> Subject: Re: [CR]Ed Litton's cambio corsa bike
> Message-ID: <20050927182851.14131.qmail@web34305.mail.mud.yahoo.com>
> In-Reply-To:
<092720051754.26413.43398759000929500000672D22007637049C0B020E049C0E0E030A08
9B@comcast.net>
> Content-Type: text/plain; charset=iso-8859-1
> MIME-Version: 1.0
> Content-Transfer-Encoding: 8bit
> Precedence: list
> Message: 1
>
> --- themaaslands@comcast.net wrote:
>
> > It should perhaps be pointed out that Ed's bike is a
> > cambio corsa bike and not a Paris-Roubaix model.
> >
> > I can give you a bit of history regarding this
> > particular frame. The lugs, drop-outs and such came
> > from what I believe was an early 1950's Aquila
> > frame. I had bought the frame sight unseen in Italy
> > and it turned out to be totally shot, so bad in fact
> > that a repair was not viable. Ed decontructed the
> > frame and retrieved the lugs, drop-outs and fork
> > crown. He then used the cambio corsa dropout jigs
> > that Roland Della Santa has and built himself the
> > frame. This worked out very well as Ed is definitely
> > taller than your average Italian from the 50's and
> > would have had great difficulty to find himself a
> > large enough frame otherwise. Ed still has a few
> > more cambio corsa dropout frames in his workshop, so
> > if you want a made to measure Ed Litton cambio corsa
> > bike, it is possible.
>
> Steven,
> Another listee posted some links to this bike, I
> think, but they didn't work for me. Can you or anybody
> post pics of the frame, build, jigging, and such? A
> few years back, Grant Petersen asked me about my
> interest in making one, I think he said he could get
> the parts and jigs, but I guess I said I wouldn't know
> what to charge as I wasn't familiar enough with the
> design.
> Joe Starck
> Madison, Wisconsin
>
>
>
> ------------------------------
>
> Date: Tue, 27 Sep 2005 14:31:07 EDT
> From: RDF1249@aol.com
> To: brianbaylis@juno.com
> Cc: classicrendezvous@bikelist.org
> Subject: Re: [CR]More about Silver vs Brass
> Message-ID: <213.a0df9d4.306ae9eb@aol.com>
> Content-Type: text/plain; charset="US-ASCII"
> MIME-Version: 1.0
> Content-Transfer-Encoding: 7bit
> Precedence: list
> Message: 2
>
>
>
>
> OK - I spoke with Bill Davidson about his recollections of this test and
as
> usual, he remembers a lot more detail than I do. I had most of it right
but
> I hate to say Brian is correct and I remembered wrong on one point. None
of
> the silver joints pulled away from the tubes in this particular test.
More
> about that in a second.
>
> The device we used was borrowed from Charlie Cunningham. Just as I said,
it
> held the front triangle rigidly while a lever was used much as a fork
would
> be in a front end crash, to wrinkle the front end, using a hydraulic jack
as
> the power. A strain gauge was hooked up to this to measure the force
> required, which would tell you how resistant the frame was against an
impact. The
> absolute amount of force required is irrelevant due to the leverage
involved,
> only the relative differences are significant. Here are the results that
> Bill remembers: With Silver, the frame wrinkled right near the points of
the
> lugs. With brass, it wrinkled about 1 cm down from the lugs. This
didn't
> change with the different tubing or lugs, just with silver vs brass.
This is as
> you might expect, since brass requires a higher temperature than silver
and
> so the heat affected zone is further out. Bill says this is significant
> because it means that the weakest point of the tube, the margin of the
> heat-affected zone, is right near those nasty stress risers - the points
of the lugs -
> in a silver brazed frame. In a lifetime of flex cycles, if it is going
to
> break from fatigue, that is where it will go first. We have seen a lot
of
> frames go like that. The brass-brazed frame which wrinkles farther
down, would
> at least be stronger or at least more uniform where the points are and
less
> likely to be taken out by fatigue cycles.
>
> Another significant thing Bill mentioned: Remember I told you about
brazing
> with a big rosebud torch to preheat the joints so you can do it faster?
We
> did some that way and some the usual way with only a small torch. Bill
said
> the preheated joints withstood a lot more force according to the strain
> gauge, although ultimately they failed in the same manner. That means
the frame
> should be able to survive a somewhat harder impact. Since we only braze
this
> way with brass (too much heat for silver) that is a point in brass's
favor.
>
> Now back to those silver joints coming apart. I didn't make this up. It
> just didn't happen during this test. We get a lot of crashed bikes in
for
> repairs, and Bill says he has seen many frames brazed with silver pull
apart
> during a crash. Not just ours, but from other very well known builders
too. I
> should point out that we have used Silver to braze also for many years on
very
> light tubing. I have seen a number of these too, and somehow remembered
them
> as being in the test. Some particular lugs are more prone to this than
> others. The Otsuya lugs that we used back the early 80s had very small
surface
> area behind the head tube, and these were more prone to coming apart, as
you
> might expect. I crashed my Davidson with these lugs in a high speed
front
> ender in 1988, and while it did wrinkle the frame pretty good, it didn't
come
> apart. Luck of the draw I think. I straightened and rode it a bit
more, and
> it eventually the .7/.4 Prestige downtube cracked so I rebuilt it. Bill
has
> seen a number of times where when the joint pulled apart, it left a thin
> layer of steel on the brazing material. He suggests that this has
something to
> do with how the metal cooled in the investment casting process, leaving a
weak
> surface layer. He started shining up the inside of lugs when he noticed
> this to remove that shear layer.
>
> Conclusions? Draw your own. It still seems to me that a frame can be
> stronger when brazed with brass and using a preheat torch in the hands of
a good
> brazer who can do it quickly, but there is nothing wrong with silver as
long
> as you don't plan to crash it. And if you crash, well, the frame is
probably
> the least of your worries.
>
> Ride safe
>
>
> Bob Freeman
> Elliott Bay Bicycles
> 2116 Western Ave
> Seattle, WA 98121
> 206-441-8144
> Home of Davidson Handbuilt Bicycles
>
>
> In a message dated 9/24/2005 11:31:13 P.M. Pacific Standard Time,
> brianbaylis@juno.com writes:
>
> I would have to see the testing device, the way you bulit the "test
> triangles", and a whole lot more before I would believe your story. No
properly
> brazed silver joint will fail before the tube in an impact. Seen lots of
them.
> Seen more broken joints (where tube did not break but braze joint did,
which is
> just as wrong with brass as with silver) on brass brazed frames than with
> silver by quite a large margin. I've seen a good number of relavatively
poorly
> brazed silver joints not fail after impact. It sounds to me like you
tested a
> bunch of improperly brazed silver joints. Probably better to use brass in
> that situation, but properly silver brazed joints have at least equal
strength
> to those of brass.
>
> For those of you out there who do not or have not built a good number of
> frames; there is no way to really decide which information is closeset to
the
> truth. Since I happen to know what I've seen and experienced, I know for
sure I
> don't buy this particular story.
>
> It is obvious that good bikes and excellent bikes can be made useing
either
> method and that the primary factor in that is the ability of the builder
and
> their intentions towards producing a quality product. But there is such a
> thing as reality. 700 frames a year is not the place for silver. Silver
is for
> those individually producing handmade frames with traits and features
that
> aren't part of low production work. It's a different world, different
> circumstances. Like I said, good that you did some testing and concluded
that for your
> circumstances brass worked better for you. Silver works better for the
type
> of work I do.
>
> Brian Baylis
> La Mesa, CA
> Show me, talk is cheap.
>
> -- RDF1249@aol.com wrote:
> I came into this thread late but I thought I would share a couple of
> tidbits.
> In the mid-80s, when we (Davidson Cycles) were building around 700 frames
> per
> year, we wanted some idea of what was going to happen to them in a crash,
so
> borrowed a destructive testing device (I forget who had it. Bicycling
Mag,
> maybe?) that simulated a front end crash. Made a bunch of front ends to
> test in
> it, with all different materials and methods but otherwise the same, and
> found, almost without exception, that the joint failed (came apart) when
> done with
> silver, and the tube failed behind the intact joint when brazed with
brass.
> What does that tell you? Well, given a hard enough impact you will
destroy
> a
> steel bike no matter, but the brass did make a stronger joint. Yes you
can
> braze at a lower temperature with silver, but if you are burning the snot
> out of
> it getting it to move around then you will do a lot more harm. I think
an
> experienced builder using brass will build a much superior bike to a
rookie
> with
> silver.
>
> It is not only the absolute temperature that is reached that degrades the
> steel, it is the length of time at that temperature. The longer it stays
> hot,
> the farther away from the joint the heat affected zone travels. It is
that
> margin of the heat affected zone that is where a frame will usually fail
in
> a
> crash. Keeping it closer to the lug, in the butted section, makes it
more
> likely
> to withstand a crash. So brazing it quickly is the answer to making the
> strongest frame. We developed a way to braze them very quickly. We
don't
> do a lot
> of lugged steel frames any more so I don't mine sharing the tricks. We
made
> little rings of brass that were the shape of the inside of the joint, and
> assembled the frame with them in there. The joint is heated quickly and
> evenly
> with a large, broad flame until red hot. You can see the brass ring in
> there as
> a shadow. Once it is gone you know the brass has melted, we switch to a
> small
> torch and work the heat around until brass comes out all the edges
evenly,
> and voila, you are done. Almost no cleanup involved afterwards. A few
of
> our
> brazers would use the big torch in one hand and the small torch in the
> other.
> We had fork crowns made with a shelf that the steerer butted against, and
> stamped out washers of brass that fit right in there and did the same
thing
> for
> the crown to steerer braze, and had rings inside the blade sockets too.
Two
> guys could braze up 30 steerer, crown, blade assemblies an hour that way.
> Again
> with almost no cleanup. And it leaves a little fillet of brass on the
> inside
> of the joint too to further strengthen it. You would never get
penetration
> that good by brazing from the outside only, and not nearly as fast.
>
> Another tidbit, and all framebuilders know this, but 853 Reynolds is
always
> brazed with brass. It doesn't get hot enough for the air-hardening to
> happen
> with silver.
>
>
>
>
>
>
>
>
>
> ------------------------------
>
> Date: Tue, 27 Sep 2005 20:36:06 +0200
> From: Amir Avitzur <avitzur@013.net>
> To: Classicrendezvous <classicrendezvous@bikelist.org>
> Subject: [CR]Saddle disassembly & riveting redux
> Message-ID: <JJEEKLDDELHGFDGDBELBEENLCFAA.avitzur@013.net.il>
> Content-Type: text/plain; charset=windows-1255
> MIME-Version: 1.0
> Content-Transfer-Encoding: 7bit
> Precedence: list
> Message: 3
>
>
> By an odd fluke, my local hardware store had a box of brass rivets,
> forgotten by the original customer.
> The rivets have a 12 mm flat head and a 4 mm diameter shaft that is 9 mm
> long.
> The shafts are solid to the middle and then hollow.
>
> As some of the respondents to my inquiry noted:
> the shaft of the rivets do all the "work",
> the heads, besides holding the rivet in place, are mostly ornamental
> that is why the root of the shaft is solid
>
> Anyway, once I got them home I had to try replacing a rivet.
> So I drilled out an old one and placed new one in its hole.
>
> Rivet replacement is not difficult.
> It can even be done without a rivet setter as follows:
>
> cut the hollow shaft radially so that it will bend over easily
> hammer a cone (I used a punch) into the opening to bend the "petals"
> evenly
> use a ball peen hammer to finish the bend and tighten the rivet
> use a ball peen hammer to contour the head over the leather
> at all times support the other side of the rivet with a block of
> hardwood or piece of metal
>
> This takes time and patience, but can look quite nice afterwards.
>
> The technique gets a lot more complicated when the leather on the saddle
has
> been completely removed.
> I'll report on that when I get to it.
>
> Amir Avitzur
> Ramat-Gan, Israel
>
>
>
>
> ------------------------------
>
> Date: Tue, 27 Sep 2005 11:47:52 -0700
> From: "Jack Gabus" <jack@shermangabus.com>
> To: <classicrendezvous@bikelist.org>
> Subject: [CR]"Blue Bianchi"
> Message-ID: <MHELKCFNLJJCPOHKBLKAAEHGGFAA.jack@shermangabus.com>
> Content-Type: text/plain;charset="iso-8859-1"
> MIME-Version: 1.0
> Content-Transfer-Encoding: 7bit
> Precedence: list
> Message: 4
>
> Well it's back. This was from two or three week ago. The infamous "Blue
> Bianchi" Now he thinks it is a DeRosa. Ok everybody chime and let's
figure
> this one out. On list please.
>
> E-Bay # 7185236156
>
> Regards,
>
> Jack
>
> Jack (Giacomo) Gabus
> Laguna Beach, CA
> jack@shermangabus.com
> http://www.wooljersey.com/
>
>
> ------------------------------
>
> Date: Tue, 27 Sep 2005 11:59:34 -0700
> From: Kurt Sperry <haxixe@gmail.com>
> Cc: classicrendezvous@bikelist.org
> Subject: Re: [CR]More about Silver vs Brass
> Message-ID: <75d04b480509271159787870d2@mail.gmail.com>
> In-Reply-To: <213.a0df9d4.306ae9eb@aol.com>
> References: <213.a0df9d4.306ae9eb@aol.com>
> Content-Type: text/plain; charset=ISO-8859-1
> MIME-Version: 1.0
> Precedence: list
> Reply-To: kurt@fineartscrimshaw.com
> Message: 5
>
> Wonderful stuff there Bob, thanks. While the methodologies might be
quibble
> d
> with, the results are still highly instructive.
> There's a TON of mythology related to our beloved lightweight bikes, some
> myths will withstand empirical testing; some won't.
> Kurt Sperry
> Bellingham WA
>
>
> >
> >
> > OK - I spoke with Bill Davidson about his recollections of this test and
> > as
> > usual, he remembers a lot more detail than I do. I had most of it right
> > but
> > I hate to say Brian is correct and I remembered wrong on one point. None
> > of
> > the silver joints pulled away from the tubes in this particular test.
Mor
> e
> > about that in a second.
> >
> > The device we used was borrowed from Charlie Cunningham. Just as I said,
> > it
> > held the front triangle rigidly while a lever was used much as a fork
> > would
> > be in a front end crash, to wrinkle the front end, using a hydraulic
jack
> > as
> > the power. A strain gauge was hooked up to this to measure the force
> > required, which would tell you how resistant the frame was against an
> > impact. The
> > absolute amount of force required is irrelevant due to the leverage
> > involved,
> > only the relative differences are significant. Here are the results that
> > Bill remembers: With Silver, the frame wrinkled right near the points of
> > the
> > lugs. With brass, it wrinkled about 1 cm down from the lugs. This didn't
> > change with the different tubing or lugs, just with silver vs brass.
This
> > is as
> > you might expect, since brass requires a higher temperature than silver
> > and
> > so the heat affected zone is further out. Bill says this is significant
> > because it means that the weakest point of the tube, the margin of the
> > heat-affected zone, is right near those nasty stress risers - the points
> > of the lugs -
> > in a silver brazed frame. In a lifetime of flex cycles, if it is going
to
> > break from fatigue, that is where it will go first. We have seen a lot
of
> > frames go like that. The brass-brazed frame which wrinkles farther down,
> > would
> > at least be stronger or at least more uniform where the points are and
> > less
> > likely to be taken out by fatigue cycles.
> >
> > Another significant thing Bill mentioned: Remember I told you about
> > brazing
> > with a big rosebud torch to preheat the joints so you can do it faster?
W
> e
> > did some that way and some the usual way with only a small torch. Bill
> > said
> > the preheated joints withstood a lot more force according to the strain
> > gauge, although ultimately they failed in the same manner. That means
the
> > frame
> > should be able to survive a somewhat harder impact. Since we only braze
> > this
> > way with brass (too much heat for silver) that is a point in brass's
> > favor.
> >
> > Now back to those silver joints coming apart. I didn't make this up. It
> > just didn't happen during this test. We get a lot of crashed bikes in
for
> > repairs, and Bill says he has seen many frames brazed with silver pull
> > apart
> > during a crash. Not just ours, but from other very well known builders
> > too. I
> > should point out that we have used Silver to braze also for many years
on
> > very
> > light tubing. I have seen a number of these too, and somehow remembered
> > them
> > as being in the test. Some particular lugs are more prone to this than
> > others. The Otsuya lugs that we used back the early 80s had very small
> > surface
> > area behind the head tube, and these were more prone to coming apart, as
> > you
> > might expect. I crashed my Davidson with these lugs in a high speed
front
> > ender in 1988, and while it did wrinkle the frame pretty good, it didn't
> > come
> > apart. Luck of the draw I think. I straightened and rode it a bit more,
> > and
> > it eventually the .7/.4 Prestige downtube cracked so I rebuilt it. Bill
> > has
> > seen a number of times where when the joint pulled apart, it left a thin
> > layer of steel on the brazing material. He suggests that this has
> > something to
> > do with how the metal cooled in the investment casting process, leaving
a
> > weak
> > surface layer. He started shining up the inside of lugs when he noticed
> > this to remove that shear layer.
> >
> > Conclusions? Draw your own. It still seems to me that a frame can be
> > stronger when brazed with brass and using a preheat torch in the hands
of
> > a good
> > brazer who can do it quickly, but there is nothing wrong with silver as
> > long
> > as you don't plan to crash it. And if you crash, well, the frame is
> > probably
> > the least of your worries.
> >
> > Ride safe
> >
> >
> > Bob Freeman
> > Elliott Bay Bicycles
> > 2116 Western Ave
> > Seattle, WA 98121
> > 206-441-8144
> > Home of Davidson Handbuilt Bicycles
> >
> >
> > fineartscrimshaw.com http://fineartscrimshaw.com
>
>
> ------------------------------
>
> _______________________________________________
>
>
> End of Classicrendezvous Digest, Vol 33, Issue 105
> **************************************************