|
|
|
Thread Tools | Display Modes |
#1
|
|||
|
|||
Do electronics soldering skills transfer to brazing bike frames?
Jute:
I'll learn to braze (I do silver soldering of electronics all the time) George: Is that low temperature stuff (ie the modern replacements for leaded solder, using an iron) or using a torch with traditional silver solder? As you would expect by now, I don't do the expected thing simply because everyone else does it that way. I have the usual electrical soldering irons but rarely use them, instead preferring to use a catalytic pencil (it literally clips into a pocket) driven by cigarette lighter gas. It goes up to 1300 degrees and I keep it going full blast, so one has to be quick to make the joint. But I design and build thermionic valve (American: tube) amps, so there are no tiny transistors, only big parts, no resistors smaller than 2W, and the Japanese handmade Kiwame that I like for sonic reasons have wires sticking out of them thicker than the tube rim on many everyday bikes, never mind racing bikes. The solder I use is 2% silver eutectic (it melts and sets at the same temperature, so when you remove the heat, the joint is instantly set). The process is really a sort of moderate temperature brazing, as the solder is intended to flow between close-fitting parts, or to be filleted around wires. Re learning to braze - do you have a local community college who will do courses in such things? Could well be interesting, even if you weren't building a frame. I'd definitely want to do it on borrowed kit first. I wasn't actually thinking of a big gas cylinder with tubes running all over the place, which has legal requirements and transport difficulties (I haven't owned a car since 1992, in part to force me to cycle, in part out of principle). I have a set of nozzles which can be operated from a gas canister that also serves as a handle. Easy to manipulate and put down. Probably more expensive in combustibles than the big tank, but I don't think on a one-bicycle scale that will be a big deal. This is a tool that could (according to the Little Fish site, a real inspiration) do real brazing I also have a big 200W soldering iron to burn teflon coating off, and tin, the thick Cardas multistrand TC5 I use for loudspeaker cable. It's a great big brutal soldering iron used for nothing else. I was just wondering if 200W is enough to heat two bike-size pipes and the lug properly. A joint made with the electronics type eutectic silver solder would definitely be weaker than one that is hard-brazed with gas (another way of distinguishing between electric iron electronic soldering and gas brazing is as "soft soldering" v "hard soldering"). But that merely raises another question or several. Is it necessary on a bike frame to have hard brazing (either brass or silver) or is it overkill? Would (lower temperature, soft) silver soldering with a big iron for heating not be good enough for bicycles? If it is such a great idea, why doesn't anyone do it? Further questions that might cast light on the choice: What is the normal failure mode of a steel bicycle frame? How often do joints come apart spontaneously? Here's a crucial test: Does a guy who regularly brazes bike parts for a living, someone like Andrew Muzi simply by way of example, believe that a soft-soldered bike by an amateur would be safe? I don't actually fancy paying for being a pioneer by landing on my face on the tarmac... Alternatively you could try a Dave Yates framebuilding course - I've read good things about those, and it would be an interesting way to get a custom frame. I visited his site a few weeks ago. Yates has so many bookings for his course, he's just about given up building bikes to order. Andre Jute Visit Jute on Amps at http://members.lycos.co.uk/fiultra/ "wonderfully well written and reasoned information for the tube audio constructor" John Broskie TubeCAD & GlassWare "an unbelievably comprehensive web site containing vital gems of wisdom" Stuart Perry Hi-Fi News & Record Review |
Ads |
#2
|
|||
|
|||
Do electronics soldering skills transfer to brazing bike frames?
Andre Jute wrote:
I also have a big 200W soldering iron to burn teflon coating off, and tin, the thick Cardas multistrand TC5 I use for loudspeaker cable. It's a great big brutal soldering iron used for nothing else. I was just wondering if 200W is enough to heat two bike-size pipes and the lug properly. I doubt it. I have been unable to reliably wet 10mm (inside dia.) loops of 10g stranded copper with a 140W iron. Copper carries heat away much faster than steel, but that's not very much metal compared to a frame joint. It would be more realistic to use a plumber's torch, since that is more or less what it's for. A joint made with the electronics type eutectic silver solder would definitely be weaker than one that is hard-brazed with gas (another way of distinguishing between electric iron electronic soldering and gas brazing is as "soft soldering" v "hard soldering"). But that merely raises another question or several. Is it necessary on a bike frame to have hard brazing (either brass or silver) or is it overkill? Not overkill-- brazing is strong enough but not wildly stronger than necessary for the job. Bond strength of common brazing fillers is higher in some cases than the yield strength of the steel being joined, but brazed joints are generally comparable in strength to welded joints even though they are physically larger. Would (lower temperature, soft) silver soldering with a big iron for heating not be good enough for bicycles? If it is such a great idea, why doesn't anyone do it? That won't work with readily available lugs. Because soft solder is much weaker than brazing material (roughly 4000 to 8000 psi tensile yield vs. 40,000 to 100,000 psi for brazing fillers), lugs would have to have very long sockets if they were to stand a chance. To allow soft solder to serve as filler metal for a bike frame, the tubes themselves might also have to be larger in diameter than normal, to provide more wetted area and proportionally lower shear stresses. In any plausible scenario, the frame tubes would be very much stronger than the joints (unless you built the frame from plumbing copper). Soft solder fillet joints are probably not feasible; I doubt that they can be made so large that they would not yield and rupture under typical riding stresses. Building a frame with soft solder might be a fun thing to try-- but in the case of success, I would advise destructively testing a soft- soldered bike frame rather than test-riding it. Chalo |
#3
|
|||
|
|||
Do electronics soldering skills transfer to brazing bike frames?
On Nov 25, 12:00*pm, Chalo wrote:
Andre Jute wrote: I also have a big 200W soldering iron to burn teflon coating off, and tin, the thick Cardas multistrand TC5 I use for loudspeaker cable. It's a great big brutal soldering iron used for nothing else. I was just wondering if 200W is enough to heat two bike-size pipes and the lug properly. I doubt it. *I have been unable to reliably wet 10mm (inside dia.) loops of 10g stranded copper with a 140W iron. *Copper carries heat away much faster than steel, but that's not very much metal compared to a frame joint. *It would be more realistic to use a plumber's torch, since that is more or less what it's for. A joint made with the electronics type eutectic silver solder would definitely be weaker than one that is hard-brazed with gas (another way of distinguishing between electric iron electronic soldering and gas brazing is as "soft soldering" v "hard soldering"). But that merely raises another question or several. Is it necessary on a bike frame to have hard brazing (either brass or silver) or is it overkill? Not overkill-- brazing is strong enough but not wildly stronger than necessary for the job. *Bond strength of common brazing fillers is higher in some cases than the yield strength of the steel being joined, but brazed joints are generally comparable in strength to welded joints even though they are physically larger. Would (lower temperature, soft) silver soldering with a big iron for heating not be good enough for bicycles? If it is such a great idea, why doesn't anyone do it? That won't work with readily available lugs. *Because soft solder is much weaker than brazing material (roughly 4000 to 8000 psi tensile yield vs. 40,000 to 100,000 psi for brazing fillers), lugs would have to have very long sockets if they were to stand a chance. *To allow soft solder to serve as filler metal for a bike frame, the tubes themselves might also have to be larger in diameter than normal, to provide more wetted area and proportionally lower shear stresses. *In any plausible scenario, the frame tubes would be very much stronger than the joints (unless you built the frame from plumbing copper). Soft solder fillet joints are probably not feasible; I doubt that they can be made so large that they would not yield and rupture under typical riding stresses. Building a frame with soft solder might be a fun thing to try-- but in the case of success, I would advise destructively testing a soft- soldered bike frame rather than test-riding it. Chalo A really terrible idea is one that sounded brilliant while it lasted -- fortunately not long enough to do anyone harm! On to the next. Thanks, Chalo. -- AJ |
#4
|
|||
|
|||
Do electronics soldering skills transfer to brazing bike frames?
"Andre Jute" wrote in message
... I wasn't actually thinking of a big gas cylinder with tubes running all over the place, which has legal requirements and transport difficulties (I haven't owned a car since 1992, in part to force me to cycle, in part out of principle). I have a set of nozzles which can be operated from a gas canister that also serves as a handle. Easy to manipulate and put down. Probably more expensive in combustibles than the big tank, but I don't think on a one-bicycle scale that will be a big deal. This is a tool that could (according to the Little Fish site, a real inspiration) do real brazing Little Fish is unfortunately down atm, but are they talking about a plain propane or butane blowtorch (as used by plumbers), or a MAPP gas torch (which will do proper silver soldering, but mind the fumes)? Neither will do real IIRC brazing - brass needs it to be hotter. The torch you have - what sort is it? Your description could fit either a blowtorch or a mapp gas torch. |
#5
|
|||
|
|||
Do electronics soldering skills transfer to brazing bike frames?
me too.
costs for aluminum tube welding equipment, estimated even after reading the book, Jute yawl read the book ? costs what? twice costs for a custom frame from A/F LLC. 3 frames to brake even. ugh ugh ugh. off course there is the arteeestic plane to evolve from but frankly itsa lotta dough, a lotta time. start early. break both legs. that said, one can evolve reliable technique for solder suck as in plumbing but but but does not brazing involving softening the metal surface ? one does not soften 16 ga wire, does one ? |
#6
|
|||
|
|||
Do electronics soldering skills transfer to brazing bikeframes?
On Tue, 25 Nov 2008 01:50:24 -0800, Andre Jute wrote:
snip But that merely raises another question or several. Is it necessary on a bike frame to have hard brazing (either brass or silver) or is it overkill? Would (lower temperature, soft) silver soldering with a big iron for heating not be good enough for bicycles? If it is such a great idea, why doesn't anyone do it? not a great idea. too weak. Further questions that might cast light on the choice: What is the normal failure mode of a steel bicycle frame? How often do joints come apart spontaneously? not very, but that's because they're usually brazed/soldered with higher strength materials. snip bottom line, in terms of subject title, yes, the skills of heating, wetting, and judging the meniscus transfer very well, but there is more to frame building than that. the prep and fluxing process is much more involved and using a gas torch, as you should, requires a reasonable degree of practice to ensure you're not over-heating the thin tubes as you're trying to get sufficient heat into a thicker section like a lug or end. many local colleges have brazing courses, usually not too expensive. sign up for one of those, get some practice in, then you can try your own projects. you will not be surprised to learn that many teachers of such courses have not only done bike stuff themselves, but they are familiar with people wanting to do so and can thus offer good advice, particularly on things like thermal expansion and how to minimize contraction distortion. if you want to build a frame, you have a couple of options for holding tubes in place prior, drilling & pinning, and jigging. big commercial jigs are hunky and steel - and very expensive, but you can make your own out of wood. yes, you stand a good chance of it catching fire, so keep some water handy. the point however is that even in conflagration mode, it will hold dimension long enough to braze the frame satisfactorily. [do this out doors. don't splash water on the frame - the excess cooling rate will make the metal brittle.] |
#7
|
|||
|
|||
Do electronics soldering skills transfer to brazing bike frames?
jim beam wrote:
bottom line, in terms of subject title, yes, the skills of heating, wetting, and judging the meniscus transfer very well, but there is more to frame building than that. * Lots more, most of which applies whether you're brazing, welding, or bandaging a frame together with cloth and resin. It's fun-- but if it were easy, we'd all roll our own (at least here in r.b.t). In my observation, soft soldering is a good way to learn what flux does and why you use it, and important concepts like relative thermal mass, letting gravity work for you, etc. But it doesn't involve nearly as much heat control, or more specifically not much "steering" the filler with gradients of heat. the prep and fluxing process is much more involved and using a gas torch, as you should, requires a reasonable degree of practice to ensure you're not over-heating the thin tubes as you're trying to get sufficient heat into a thicker section like a lug or end. Yep. The new toy at Austin Bike Zoo is a gas fluxer-- a bottle that sits in one of the gas lines, adds some kind of borate chemical as the gas bubbles through, and turns the flame green rather than blue. It also allows good wetting and bright, clean joints on dry metal, and almost no clean-up afterwards. I approve. Chalo |
#8
|
|||
|
|||
Do electronics soldering skills transfer to brazing bike frames?
Andre Jute wrote:
Chalo wrote: [...] Building a frame with soft solder might be a fun thing to try-- but in the case of success, I would advise destructively testing a soft- soldered bike frame rather than test-riding it. A really terrible idea is one that sounded brilliant while it lasted -- fortunately not long enough to do anyone harm! On to the next. I forgot to encourage you to get a simple MAPP/air torch (like saavy plumbers use) and some 45% silver filler and white paste flux. That would not give you enough heat or heat control to do a bottom bracket joint, but you could definitely teach yourself to do the occasional custom brazeons, household repair, and maybe bijoux for your favorite companions. If you really take to it, you could consider tooling up for the real deal-- but if you find it not to your liking, at least it's a cheap experiment and opportunity to learn a new trick. Chalo |
#9
|
|||
|
|||
Do electronics soldering skills transfer to brazing bike frames?
http://www.bikeschool.com/ The effects of differing bicycle frame geometry on muscle recruitment strategies and power during a 30-second Wingate anaerobic test by Patrick Hills-Meyer Thesis/dissertation : Manuscript Archival Material Language: English Publisher: 2004. http://www.worldcat.org/search?q=bic...&qt=first_page http://www.worldcat.org/search?q=bic...t=results_page enter A.com see Talbot http://www.worldcat.org/search?q=bic...t=results_page every wonder abt Avery? Oral history interview with Catherine Berry Pilcher Avery, 1981 February , excerpt 01 by Avery, Catherine Berry Pilcher, 1894-1982 (Interviewee); Thornton, Leanne (Interviewer) Type: Downloadable audiobook; English Publisher: Nashville, Tn. : Nashville Public Library, 2006. OCLC: 82538817 Web Resources: digital.library.nashville.org The effects of differing bicycle frame geometry on muscle recruitment strategies and power during a 30-second Wingate anaerobic test by Patrick Hills-Meyer Thesis/dissertation : Manuscript Archival Material Language: English Publisher: 2004. world cat has loads more info than when last I searched |
#10
|
|||
|
|||
Do electronics soldering skills transfer to brazing bike frames?
ooops
see Talbot http://www.amazon.com/s/ref=nb_ss_b_...icycle+fr ame see Talbot on ILL tell him he has a parking ticket |
|
Thread Tools | |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
ot bike tail light--help needed electronics | ilaboo[_2_] | General | 17 | January 4th 08 02:45 AM |
bike dealer math skills | Mike Jacoubowsky | General | 2 | September 29th 07 01:32 AM |
Think you have good bike handling skills? | [email protected] | Racing | 10 | October 7th 06 09:40 AM |
Motorcycle skills - Bicycle skills | Peter Fox | UK | 10 | June 7th 05 01:04 PM |
Great Bike Skills | Gags | Australia | 6 | October 23rd 04 02:21 PM |