Mercian

On Tue, 19 Jan 2021 21:59:11 -0000 (UTC), News 2021
wrote:

On Tue, 19 Jan 2021 18:48:34 +0100, Tosspot scribed:

On 18/01/2021 20:21, Tom Kunich wrote:
On Monday, January 18, 2021 at 6:45:41 AM UTC-8, Tosspot wrote:
On 17/01/2021 21:16, Tom Kunich wrote:
On Sunday, January 17, 2021 at 11:57:14 AM UTC-8, Tom Kunich wrote:
I was of the opinion that Mercian had gone out of business but I see
that not only are they still in business but they are building a
very wide variety of bikes. Now my experience with the Waterford/PDG
Schwinn's were that they were not the Pretty Damn Good that the name
suggests, they were still good bikes.

But my experience with Mercians was in every case I was entirely
satisfied with the bikes. Probably the only reason I parted with
them was to get better paint since a D&D paintjob was about as
expensive as a new bike. And at the time I was riding Mercian they
used a paint job that would scratch if you looked sideways at them.

http://www.merciancycles.co.uk/frames/
Nothing looks better than nice lugged brazed frame. Even better if
it's Ti...
Tell us about these lugged and brazed titanium frames. You should be a
little clearer on your responses. I'm sure you know better than what
you wrote.

Look, I can fantasize as much as the next man.

You *could* braze titanium though? Wouldn't it just have to be in an
oxygen free environment?

Err,, it might be my lac of life experience, but I've never come across
free standing titanium. As far as i know, it s sold as a minor additive
in various grades of steel tubing, jst like chromium in stainless tubing.

So, given the chance, I'd swing a brazing torch onto it.

Now, magnesium, different matter.

https://www.titaniumjoe.com/
https://www.mcmaster.com/titanium-tubing/

I certified as a titanium welder once. It was welded in a clear
plastic box flooded with argon and using an argon shielded arc (TIG)
and the slightest coloring from heat was cause to reject the weld.
Later, a far better welder then I told me that they had some success
in welding titanium by flooding both the front and back of the item
with high flow rates of argon without the box.
--
Cheers,

John B.

On Tue, 19 Jan 2021 14:40:43 -0500, Frank Krygowski
wrote:

On 1/19/2021 1:08 PM, AMuzi wrote:
On 1/19/2021 11:48 AM, Tosspot wrote:
On 18/01/2021 20:21, Tom Kunich wrote:
On Monday, January 18, 2021 at 6:45:41 AM UTC-8, Tosspot
wrote:
On 17/01/2021 21:16, Tom Kunich wrote:
On Sunday, January 17, 2021 at 11:57:14 AM UTC-8, Tom
Kunich
wrote:
I was of the opinion that Mercian had gone out of
business but
I see that not only are they still in business but they
are
building a very wide variety of bikes. Now my
experience with
the Waterford/PDG Schwinn's were that they were not the
Pretty
Damn Good that the name suggests, they were still good
bikes.

But my experience with Mercians was in every case I was
entirely satisfied with the bikes. Probably the only
reason I
parted with them was to get better paint since a D&D
paintjob
was about as expensive as a new bike. And at the time I
was
riding Mercian they used a paint job that would scratch
if you
looked sideways at them.

http://www.merciancycles.co.uk/frames/
Nothing looks better than nice lugged brazed frame. Even
better if
it's Ti...
Tell us about these lugged and brazed titanium frames. You
should be
a little clearer on your responses. I'm sure you know
better than
what you wrote.

Look, I can fantasize as much as the next man.

You *could* braze titanium though?* Wouldn't it just have to
be in an oxygen free environment?


What would you suggest for a filler material? Not bronze.

ISTR there are silver alloys and fluxes for brazing Ti. Maybe?

At any rate you're not in a TIG Argon environment so you would have to
return to the argon sealed booth of 40 years ago. Futzy but doable. Open
air braze on Ti is out, the material is very reactive with a self
destructive streak.

Then there's metalworking. Ti is famously difficult to work and tooling
for stamped and welded lugs would be prohibitive. It may be possible to
weld up tube sections in the way that Cinelli and Pogliaghi welded
oversized joints for track tandems.* Again, possible but arduous.
Aesthetically, you're still looking at a TIG joint on the lug instead of
the tube itself.

At the end of that where's the gain? Welded titanium is a well advanced
technology, cheap, strong, simple. What would a brazed sleeve Ti frame
offer?

It's obvious the only benefit would be aesthetic. So the solution would
be faux lugs glued glued in place to cover the welds! Stick on prettiness!

Not much different than rear spoilers on an econobox car, tattoos and
nose rings, "team" jerseys on MAMILS, etc.

I've always wondered about these titanium bicycles. The SR-71 had some
titanium and drilling it was very much like drilling stainless steel
except it work hardened even quicker then stainless but if you kept
the drill cutting it didn't seem like a very "hard" metal compared
with chrom-molybdenum steels. 4130 or 40, for example.
--
Cheers,

John B.

On Tue, 19 Jan 2021 12:08:05 -0600, AMuzi wrote:

On 1/19/2021 11:48 AM, Tosspot wrote:
On 18/01/2021 20:21, Tom Kunich wrote:
On Monday, January 18, 2021 at 6:45:41 AM UTC-8, Tosspot
wrote:
On 17/01/2021 21:16, Tom Kunich wrote:
On Sunday, January 17, 2021 at 11:57:14 AM UTC-8, Tom
Kunich
wrote:
I was of the opinion that Mercian had gone out of
business but
I see that not only are they still in business but they
are
building a very wide variety of bikes. Now my
experience with
the Waterford/PDG Schwinn's were that they were not the
Pretty
Damn Good that the name suggests, they were still good
bikes.

But my experience with Mercians was in every case I was
entirely satisfied with the bikes. Probably the only
reason I
parted with them was to get better paint since a D&D
paintjob
was about as expensive as a new bike. And at the time I
was
riding Mercian they used a paint job that would scratch
if you
looked sideways at them.

http://www.merciancycles.co.uk/frames/
Nothing looks better than nice lugged brazed frame. Even
better if
it's Ti...
Tell us about these lugged and brazed titanium frames. You
should be
a little clearer on your responses. I'm sure you know
better than
what you wrote.

Look, I can fantasize as much as the next man.

You *could* braze titanium though? Wouldn't it just have to
be in an oxygen free environment?


What would you suggest for a filler material? Not bronze.

ISTR there are silver alloys and fluxes for brazing Ti. Maybe?

At any rate you're not in a TIG Argon environment so you
would have to return to the argon sealed booth of 40 years
ago. Futzy but doable. Open air braze on Ti is out, the
material is very reactive with a self destructive streak.

Then there's metalworking. Ti is famously difficult to work
and tooling for stamped and welded lugs would be
prohibitive. It may be possible to weld up tube sections in
the way that Cinelli and Pogliaghi welded oversized joints
for track tandems. Again, possible but arduous.
Aesthetically, you're still looking at a TIG joint on the
lug instead of the tube itself.

At the end of that where's the gain? Welded titanium is a
well advanced technology, cheap, strong, simple. What would
a brazed sleeve Ti frame offer?

Actually, there were some successful welded-Ti-lug designs
around 1990 with carbon tubes glued in.

https://www.cxmagazine.com/tbt-john-...oga-eric-rumpf

Something like that maybe, Ti tubes glued in Ti sleeves?
lugged but not brazed.

A company named Superior Flux&Mfg Co. makes a flux and filler material
for brazing titanium - Upon heating the titanium brazing flux, the
flux’s binder burns off; the inorganic fluorides sinter and then melt
at about 1000-1100°F (538-590°C). When molten the titanium brazing
flux protects the titanium substrate from oxidation. However the
titanium brazing flux no longer protects the titanium against
oxidation if the substrate is heated much above 1500°F/815°C (cherry
red).

On the other hand, as you say, TIG welding with argon back shielding
inside the tubes would be so much easier and produce a stronger joint.
--
Cheers,

John B.

On 1/19/2021 3:59 PM, News 2021 wrote:
On Tue, 19 Jan 2021 18:48:34 +0100, Tosspot scribed:

On 18/01/2021 20:21, Tom Kunich wrote:
On Monday, January 18, 2021 at 6:45:41 AM UTC-8, Tosspot wrote:
On 17/01/2021 21:16, Tom Kunich wrote:
On Sunday, January 17, 2021 at 11:57:14 AM UTC-8, Tom Kunich wrote:
I was of the opinion that Mercian had gone out of business but I see
that not only are they still in business but they are building a
very wide variety of bikes. Now my experience with the Waterford/PDG
Schwinn's were that they were not the Pretty Damn Good that the name
suggests, they were still good bikes.

But my experience with Mercians was in every case I was entirely
satisfied with the bikes. Probably the only reason I parted with
them was to get better paint since a D&D paintjob was about as
expensive as a new bike. And at the time I was riding Mercian they
used a paint job that would scratch if you looked sideways at them.

http://www.merciancycles.co.uk/frames/
Nothing looks better than nice lugged brazed frame. Even better if
it's Ti...
Tell us about these lugged and brazed titanium frames. You should be a
little clearer on your responses. I'm sure you know better than what
you wrote.

Look, I can fantasize as much as the next man.

You *could* braze titanium though? Wouldn't it just have to be in an
oxygen free environment?

Err,, it might be my lac of life experience, but I've never come across
free standing titanium. As far as i know, it s sold as a minor additive
in various grades of steel tubing, jst like chromium in stainless tubing.

So, given the chance, I'd swing a brazing torch onto it.

Now, magnesium, different matter.


Titanium tube, either CP or Type 9 (94% Ti with aluminum &
vanadium alloyed), is a commercial commodity. (good luck
forming chainstays from stock round tube).

There's no way to join titanium with open flame systems,
it's highly reactive.

--
Andrew Muzi
www.yellowjersey.org/
Open every day since 1 April, 1971

On 1/19/2021 4:59 PM, John B. wrote:
On Tue, 19 Jan 2021 18:48:34 +0100, Tosspot wrote:

On 18/01/2021 20:21, Tom Kunich wrote:
On Monday, January 18, 2021 at 6:45:41 AM UTC-8, Tosspot wrote:
On 17/01/2021 21:16, Tom Kunich wrote:
On Sunday, January 17, 2021 at 11:57:14 AM UTC-8, Tom Kunich
wrote:
I was of the opinion that Mercian had gone out of business but
I see that not only are they still in business but they are
building a very wide variety of bikes. Now my experience with
the Waterford/PDG Schwinn's were that they were not the Pretty
Damn Good that the name suggests, they were still good bikes.

But my experience with Mercians was in every case I was
entirely satisfied with the bikes. Probably the only reason I
parted with them was to get better paint since a D&D paintjob
was about as expensive as a new bike. And at the time I was
riding Mercian they used a paint job that would scratch if you
looked sideways at them.

http://www.merciancycles.co.uk/frames/
Nothing looks better than nice lugged brazed frame. Even better if
it's Ti...
Tell us about these lugged and brazed titanium frames. You should be
a little clearer on your responses. I'm sure you know better than
what you wrote.

Look, I can fantasize as much as the next man.

You *could* braze titanium though? Wouldn't it just have to be in an
oxygen free environment?

I've never done it but from what I read titanium brazing must be done
in a vacuum or chlorine gas atmosphere as at higher temperature as
titanium is reactive to oxygen absorption and hydrogen absorption. Or
one could use an electric arc in an argon atmosphere, as in TIG
welding.


There are arc braze systems for steel so I assume a silver
arc system might be possible for Ti but a sleeved joint and
arc are not compatible.

--
Andrew Muzi
www.yellowjersey.org/
Open every day since 1 April, 1971

On 1/19/2021 5:15 PM, John B. wrote:
On Tue, 19 Jan 2021 14:40:43 -0500, Frank Krygowski
wrote:

On 1/19/2021 1:08 PM, AMuzi wrote:
On 1/19/2021 11:48 AM, Tosspot wrote:
On 18/01/2021 20:21, Tom Kunich wrote:
On Monday, January 18, 2021 at 6:45:41 AM UTC-8, Tosspot
wrote:
On 17/01/2021 21:16, Tom Kunich wrote:
On Sunday, January 17, 2021 at 11:57:14 AM UTC-8, Tom
Kunich
wrote:
I was of the opinion that Mercian had gone out of
business but
I see that not only are they still in business but they
are
building a very wide variety of bikes. Now my
experience with
the Waterford/PDG Schwinn's were that they were not the
Pretty
Damn Good that the name suggests, they were still good
bikes.

But my experience with Mercians was in every case I was
entirely satisfied with the bikes. Probably the only
reason I
parted with them was to get better paint since a D&D
paintjob
was about as expensive as a new bike. And at the time I
was
riding Mercian they used a paint job that would scratch
if you
looked sideways at them.

http://www.merciancycles.co.uk/frames/
Nothing looks better than nice lugged brazed frame. Even
better if
it's Ti...
Tell us about these lugged and brazed titanium frames. You
should be
a little clearer on your responses. I'm sure you know
better than
what you wrote.

Look, I can fantasize as much as the next man.

You *could* braze titanium though? Wouldn't it just have to
be in an oxygen free environment?


What would you suggest for a filler material? Not bronze.

ISTR there are silver alloys and fluxes for brazing Ti. Maybe?

At any rate you're not in a TIG Argon environment so you would have to
return to the argon sealed booth of 40 years ago. Futzy but doable. Open
air braze on Ti is out, the material is very reactive with a self
destructive streak.

Then there's metalworking. Ti is famously difficult to work and tooling
for stamped and welded lugs would be prohibitive. It may be possible to
weld up tube sections in the way that Cinelli and Pogliaghi welded
oversized joints for track tandems. Again, possible but arduous.
Aesthetically, you're still looking at a TIG joint on the lug instead of
the tube itself.

At the end of that where's the gain? Welded titanium is a well advanced
technology, cheap, strong, simple. What would a brazed sleeve Ti frame
offer?

It's obvious the only benefit would be aesthetic. So the solution would
be faux lugs glued glued in place to cover the welds! Stick on prettiness!

Not much different than rear spoilers on an econobox car, tattoos and
nose rings, "team" jerseys on MAMILS, etc.

I've always wondered about these titanium bicycles. The SR-71 had some
titanium and drilling it was very much like drilling stainless steel
except it work hardened even quicker then stainless but if you kept
the drill cutting it didn't seem like a very "hard" metal compared
with chrom-molybdenum steels. 4130 or 40, for example.


It's not especially hard[1] but you're right about
drilling/milling/turning. In theory the chip should pull the
heat away if your speed and cut are right but in practice Ti
is 'grabby' and snaps off drill bits, mills and taps with
amazing efficiency. The day I met Gary Helfrich he had a
new Merlin over his shoulder with a 27.2mm eight flute
reamer stump sticking out the top. He said about half of it
flew past his ear.

[1] hacksaws and files no problem, cuts easier than mild steel.
--
Andrew Muzi
www.yellowjersey.org/
Open every day since 1 April, 1971

On 1/19/2021 9:26 PM, AMuzi wrote:
On 1/19/2021 5:15 PM, John B. wrote:
On Tue, 19 Jan 2021 14:40:43 -0500, Frank Krygowski
wrote:

On 1/19/2021 1:08 PM, AMuzi wrote:
On 1/19/2021 11:48 AM, Tosspot wrote:
On 18/01/2021 20:21, Tom Kunich wrote:
On Monday, January 18, 2021 at 6:45:41 AM UTC-8, Tosspot
wrote:
On 17/01/2021 21:16, Tom Kunich wrote:
On Sunday, January 17, 2021 at 11:57:14 AM UTC-8, Tom
Kunich
wrote:
I was of the opinion that Mercian had gone out of
business but
I see that not only are they still in business but they
are
building a very wide variety of bikes. Now my
experience with
the Waterford/PDG Schwinn's were that they were not the
Pretty
Damn Good that the name suggests, they were still good
bikes.

But my experience with Mercians was in every case I was
entirely satisfied with the bikes. Probably the only
reason I
parted with them was to get better paint since a D&D
paintjob
was about as expensive as a new bike. And at the time I
was
riding Mercian they used a paint job that would scratch
if you
looked sideways at them.

http://www.merciancycles.co.uk/frames/
Nothing looks better than nice lugged brazed frame. Even
better if
it's Ti...
Tell us about these lugged and brazed titanium frames. You
should be
a little clearer on your responses. I'm sure you know
better than
what you wrote.

Look, I can fantasize as much as the next man.

You *could* braze titanium though?Â* Wouldn't it just have to
be in an oxygen free environment?


What would you suggest for a filler material? Not bronze.

ISTR there are silver alloys and fluxes for brazing Ti. Maybe?

At any rate you're not in a TIG Argon environment so you would have to
return to the argon sealed booth of 40 years ago. Futzy but doable.
Open
air braze on Ti is out, the material is very reactive with a self
destructive streak.

Then there's metalworking. Ti is famously difficult to work and tooling
for stamped and welded lugs would be prohibitive. It may be possible to
weld up tube sections in the way that Cinelli and Pogliaghi welded
oversized joints for track tandems.Â* Again, possible but arduous.
Aesthetically, you're still looking at a TIG joint on the lug
instead of
the tube itself.

At the end of that where's the gain? Welded titanium is a well advanced
technology, cheap, strong, simple. What would a brazed sleeve Ti frame
offer?

It's obvious the only benefit would be aesthetic. So the solution would
be faux lugs glued glued in place to cover the welds! Stick on
prettiness!

Not much different than rear spoilers on an econobox car, tattoos and
nose rings, "team" jerseys on MAMILS, etc.

I've always wondered about these titanium bicycles. The SR-71 had some
titanium and drilling it was very much like drilling stainless steel
except it work hardened even quicker then stainless but if you kept
the drill cutting it didn't seem like a very "hard" metal compared
with chrom-molybdenum steels. 4130 or 40, for example.


It's not especially hard[1] but you're right about
drilling/milling/turning. In theory the chip should pull the heat away
if your speed and cut are right but in practice Ti is 'grabby' and snaps
off drill bits, mills and taps with amazing efficiency.Â* The day I met
Gary Helfrich he had a new Merlin over his shoulder with a 27.2mm eight
flute reamer stump sticking out the top. He said about half of it flew
past his ear.

[1] hacksaws and files no problem, cuts easier than mild steel.

Well, an interesting incident in our machine shop lab. (This happened
under a different instructor, who related it to me.)

The 2 person student teams made several parts, and had _just_ enough
time to do all the parts of the projects if they moved along briskly.
One of the parts was cut and turned from a 2" diameter bar of mild steel.

This one student team took forever to cut the 2" bar to length using the
power hacksaw. Then they were taking longer than forever to turn one end
of it down to 1" diameter (plus or minus 0.030").

When the instructor finally decided to see why they were having so much
trouble, he found they had somehow grabbed a 2" bar of titanium that was
in the stock rack by mistake.

--
- Frank Krygowski

On 1/19/2021 4:59 PM, News 2021 wrote:

Err,, it might be my lac of life experience, but I've never come across
free standing titanium. As far as i know, it s sold as a minor additive
in various grades of steel tubing, jst like chromium in stainless tubing.

It exists. Within my easy riding distance is a factory that produces
titanium parts in various titanium alloys. One friend of mine just
retired from an engineering job there.

Anecdote: Our university's former head machinist used to work at a
different university. Someone there was doing some sort of testing on
titanium sheets, and he helped with the project.

He said that when the project was over, they were going to throw the
titanium sheets away. He claims he asked and was given permission to
take them home.

So, last I heard, he had a storage shed in his back yard with a sheet
titanium roof. That's something that's going to puzzle future
archeologists.


--
- Frank Krygowski

On Tue, 19 Jan 2021 22:19:52 -0500, Frank Krygowski
wrote:

On 1/19/2021 9:26 PM, AMuzi wrote:
On 1/19/2021 5:15 PM, John B. wrote:
On Tue, 19 Jan 2021 14:40:43 -0500, Frank Krygowski
wrote:

On 1/19/2021 1:08 PM, AMuzi wrote:
On 1/19/2021 11:48 AM, Tosspot wrote:
On 18/01/2021 20:21, Tom Kunich wrote:
On Monday, January 18, 2021 at 6:45:41 AM UTC-8, Tosspot
wrote:
On 17/01/2021 21:16, Tom Kunich wrote:
On Sunday, January 17, 2021 at 11:57:14 AM UTC-8, Tom
Kunich
wrote:
I was of the opinion that Mercian had gone out of
business but
I see that not only are they still in business but they
are
building a very wide variety of bikes. Now my
experience with
the Waterford/PDG Schwinn's were that they were not the
Pretty
Damn Good that the name suggests, they were still good
bikes.

But my experience with Mercians was in every case I was
entirely satisfied with the bikes. Probably the only
reason I
parted with them was to get better paint since a D&D
paintjob
was about as expensive as a new bike. And at the time I
was
riding Mercian they used a paint job that would scratch
if you
looked sideways at them.

http://www.merciancycles.co.uk/frames/
Nothing looks better than nice lugged brazed frame. Even
better if
it's Ti...
Tell us about these lugged and brazed titanium frames. You
should be
a little clearer on your responses. I'm sure you know
better than
what you wrote.

Look, I can fantasize as much as the next man.

You *could* braze titanium though?* Wouldn't it just have to
be in an oxygen free environment?


What would you suggest for a filler material? Not bronze.

ISTR there are silver alloys and fluxes for brazing Ti. Maybe?

At any rate you're not in a TIG Argon environment so you would have to
return to the argon sealed booth of 40 years ago. Futzy but doable.
Open
air braze on Ti is out, the material is very reactive with a self
destructive streak.

Then there's metalworking. Ti is famously difficult to work and tooling
for stamped and welded lugs would be prohibitive. It may be possible to
weld up tube sections in the way that Cinelli and Pogliaghi welded
oversized joints for track tandems.* Again, possible but arduous.
Aesthetically, you're still looking at a TIG joint on the lug
instead of
the tube itself.

At the end of that where's the gain? Welded titanium is a well advanced
technology, cheap, strong, simple. What would a brazed sleeve Ti frame
offer?

It's obvious the only benefit would be aesthetic. So the solution would
be faux lugs glued glued in place to cover the welds! Stick on
prettiness!

Not much different than rear spoilers on an econobox car, tattoos and
nose rings, "team" jerseys on MAMILS, etc.

I've always wondered about these titanium bicycles. The SR-71 had some
titanium and drilling it was very much like drilling stainless steel
except it work hardened even quicker then stainless but if you kept
the drill cutting it didn't seem like a very "hard" metal compared
with chrom-molybdenum steels. 4130 or 40, for example.


It's not especially hard[1] but you're right about
drilling/milling/turning. In theory the chip should pull the heat away
if your speed and cut are right but in practice Ti is 'grabby' and snaps
off drill bits, mills and taps with amazing efficiency.* The day I met
Gary Helfrich he had a new Merlin over his shoulder with a 27.2mm eight
flute reamer stump sticking out the top. He said about half of it flew
past his ear.

[1] hacksaws and files no problem, cuts easier than mild steel.

Well, an interesting incident in our machine shop lab. (This happened
under a different instructor, who related it to me.)

The 2 person student teams made several parts, and had _just_ enough
time to do all the parts of the projects if they moved along briskly.
One of the parts was cut and turned from a 2" diameter bar of mild steel.

This one student team took forever to cut the 2" bar to length using the
power hacksaw. Then they were taking longer than forever to turn one end
of it down to 1" diameter (plus or minus 0.030").

When the instructor finally decided to see why they were having so much
trouble, he found they had somehow grabbed a 2" bar of titanium that was
in the stock rack by mistake.

For a short time, before they were fully staffed, we (the SAC Wing)
did some work on the SR-71 which has mostly drilling holes and
removing screws, but my experience was that drilling titanium was much
like drilling stainless steel, it wasn't especially hard but did work
harden very, very, rapidly if you let the drill slip, i.e. rotate
without cutting. Also the SR Guys told us that they had to wash the
airplanes with some sort of special stuff because normal tap water
caused corrosion.
--
Cheers,

John B.