On Sunday, January 1, 2023 at 4:04:49 PM UTC-8, AMuzi wrote:
> On 1/1/2023 3:36 PM, Tom Kunich wrote:
> > On Sunday, January 1, 2023 at 11:01:22 AM UTC-8, AMuzi wrote:
> >> On 1/1/2023 11:36 AM, Tom Kunich wrote:
> >>> On Sunday, January 1, 2023 at 9:31:00 AM UTC-8, Lou Holtman wrote:
> >>>> On Sunday, January 1, 2023 at 5:50:15 PM UTC+1, AMuzi wrote:
> >>>>> On 1/1/2023 10:31 AM, Tom Kunich wrote:
> >>>>>> On Saturday, December 31, 2022 at 7:50:33 PM UTC-8, doug....@gmail..com wrote:
> >>>>>>>>> So my question is: Can you braze with a regular propane torch?
> >>>>>>>>>
> >>>>>>>> No, not hot enough.
> >>>>>>>> But propane-oxygen is an excellent clean flame for brazing.
> >>>>>>>>
> >>>>>>>> I prefer it for filling lugs and big castings such as BB and
> >>>>>>>> crowns, where the time needed to properly fill would have
> >>>>>>>> left much more dirt from acetylene.
> >>>>>>> What I don't understand is how u get the shit to stick! I took an old bike frame, don't remember how i prepped the joint, took a thin brass rod and used a #0 tip, probably, using oxy-acet, heated the work , heated the rod and dipped in in a tin of flux, and ... could not get the brass to stick to the steel, it just ran right off.
> >>>>>>> I am pretty sure I successfully brazed in HS shop, and definitely sure I successfully silver-soldered. What I was using looked like brass to me and failed the magnet test. Was i using the wrong rod, the wrong flux, or did not prep correctly the area of the old frame?
> >>>>>>
> >>>>>> The tubes have to be prepped by sanding them or chemically etching them clean and you have to use flux which helps the bronze to adhere to the steel. As a rule, like metals will mix but you need flux to mix dissimilar metals. And you have to use the correct flux for the job and you cannot overheat the flux which is usually shown by it burning or turning black. From my memory damage I can't remember where I learned rather complete welding and brazing, but it is just like programming - when I sat down in front of the computer everything just came back.
> >>>>>>
> >>>>>> But after pricing a welding/brazing outfit I think I will just take it to one of the craigslist people who would do this for a third the price and I won't have the tanks and stuff to find a place for in my garage.
> >>>>>>
> >>>>> Mr Krygowski has shared his experience with amateur fork
> >>>>> builders. It was not a pleasant experience.
> >>>> Exactly what I was thinking. I can't understand why Tom would not follow your advice and get a fork from Waterford(?) for 400 dollar especially with his history.
> >>>>
> >>>> Lou
> >>>
> >>> Lou, you sound like you have a fear of breaking a carbon fork. Steel is quite different and if you have the correct components a safe fork is quite easy to make. I have absolutely no fear of a steel fork that I would make. Steel is not carbon fiber.
> >>>
> >> Both materials have their failure rates (as does every
> >> thing) but the rate is higher in steel than in carbon.
> >
> > So when was the last time you saw a Colnago Super or Mexico fail?
> >
> Forks, not recently. Frames regularly.
> http://www.yellowjersey.org/photosfromthepast/col162d.jpg
>
> Which implies you'd do well to buy a Colnago fork.
> --
> Andrew Muzi
> <www.yellowjersey.org/>
> Open every day since 1 April, 1971

I have has hundreds of steel bikes and have never seen a failure., I did see some failures in department store bikes But those are not made for reliability but for pure cheap utility.

On Sunday, January 1, 2023 at 7:34:20 PM UTC-8, AMuzi wrote:
> On 1/1/2023 8:40 PM, John B. wrote:
> > On Sun, 01 Jan 2023 19:59:19 -0600, AMuzi <a...@yellowjersey.org> wrote:
> >
> >> On 1/1/2023 7:03 PM, John B. wrote:
> >>> On Sun, 01 Jan 2023 18:54:39 -0600, AMuzi <a...@yellowjersey.org> wrote:
> >>>
> >>>> On 1/1/2023 6:13 PM, John B. wrote:
> >>>>> On Sun, 1 Jan 2023 09:36:53 -0800 (PST), Tom Kunich
> >>>>> <cycl...@gmail.com> wrote:
> >>>>>
> >>>>>> On Sunday, January 1, 2023 at 9:31:00 AM UTC-8, Lou Holtman wrote:
> >>>>>>> On Sunday, January 1, 2023 at 5:50:15 PM UTC+1, AMuzi wrote:
> >>>>>>>> On 1/1/2023 10:31 AM, Tom Kunich wrote:
> >>>>>>>>> On Saturday, December 31, 2022 at 7:50:33 PM UTC-8, doug....@gmail.com wrote:
> >>>>>>>>>>>> So my question is: Can you braze with a regular propane torch?
> >>>>>>>>>>>>
> >>>>>>>>>>> No, not hot enough.
> >>>>>>>>>>> But propane-oxygen is an excellent clean flame for brazing.
> >>>>>>>>>>>
> >>>>>>>>>>> I prefer it for filling lugs and big castings such as BB and
> >>>>>>>>>>> crowns, where the time needed to properly fill would have
> >>>>>>>>>>> left much more dirt from acetylene.
> >>>>>>>>>> What I don't understand is how u get the shit to stick! I took an old bike frame, don't remember how i prepped the joint, took a thin brass rod and used a #0 tip, probably, using oxy-acet, heated the work , heated the rod and dipped in in a tin of flux, and ... could not get the brass to stick to the steel, it just ran right off.
> >>>>>>>>>> I am pretty sure I successfully brazed in HS shop, and definitely sure I successfully silver-soldered. What I was using looked like brass to me and failed the magnet test. Was i using the wrong rod, the wrong flux, or did not prep correctly the area of the old frame?
> >>>>>>>>>
> >>>>>>>>> The tubes have to be prepped by sanding them or chemically etching them clean and you have to use flux which helps the bronze to adhere to the steel. As a rule, like metals will mix but you need flux to mix dissimilar metals. And you have to use the correct flux for the job and you cannot overheat the flux which is usually shown by it burning or turning black. From my memory damage I can't remember where I learned rather complete welding and brazing, but it is just like programming - when I sat down in front of the computer everything just came back.
> >>>>>>>>>
> >>>>>>>>> But after pricing a welding/brazing outfit I think I will just take it to one of the craigslist people who would do this for a third the price and I won't have the tanks and stuff to find a place for in my garage.
> >>>>>>>>>
> >>>>>>>> Mr Krygowski has shared his experience with amateur fork
> >>>>>>>> builders. It was not a pleasant experience.
> >>>>
> >>>>>>> Exactly what I was thinking. I can't understand why Tom would not follow your advice and get a fork from Waterford(?) for 400 dollar especially with his history.
> >>>>>>>
> >>>>>>> Lou
> >>>>>>
> >>>>>> Lou, you sound like you have a fear of breaking a carbon fork. Steel is quite different and if you have the correct components a safe fork is quite easy to make. I have absolutely no fear of a steel fork that I would make. Steel is not carbon fiber.
> >>>>>
> >>>>> If, as you say, "a safe fork is quite easy to make" why all the posts
> >>>>> from a "Tom Kunich" about how to put a steel fork together?
> >>>>>
> >>>>
> >>>>
> >>>> Why not? What ever could go wrong?
> >>>>
> >>>> http://www.yellowjersey.org/photosfromthepast/failfork.jpg
> >>>> http://www.yellowjersey.org/fkpardo.jpg
> >>>> http://www.yellowjersey.org/photosfromthepast/fkbs19a.jpg
> >>>> http://www.yellowjersey.org/axsfk16.jpg
> >>>
> >>> Good Lord! Is the quality of the work that you do?
> >>>
> >>
> >> Those are all 'before' pictures.
> >>
> >> Undoing and rectifying build errors, crashes, corrosion and
> >> the vicissitudes of time are pretty much what I do all day.
> >
> > Yes, I was being a "smart ass".
> >
> > But do you find a lot of building errors? I have one bike, built in
> > Japan I think, that must have been 20 years old when I bought it and
> > with no corrosion (that I could find) in the tubes and no failures in
> > joints. I did replace the wheels and I think I remember the head
> > bearings, and other then that painted the thing. and it' still going.
> >
> No, I do not. They are rare oddities. Which is why they are
> interesting.
> --
> Andrew Muzi
> <www.yellowjersey.org/>
> Open every day since 1 April, 1971

I suppose that in your business you see the very worst cases and can present those but they are so rare that they certainly would never appear in most other bike shops.
To compare the failure rate of carbon fiber bikes, most of which are reasonably new with 30 year old steel bikes though couldn't possibly make a carbon fiber frameset look good by any stretch of the imagination.

I remember ONE good steel bike failure and it was a custom made Steelman. It had a break in the top tube at the head tube. And it had clearly been overheated. And the break occurred less than a month after the owner had it delivered.