Frames and Framebuilding (1970-1979) Frame Design and Building Practices in 1973
#1
Senior Member
Thread Starter
Join Date: Aug 2010
Location: Central Florida, USA
Posts: 1,990
Bikes: Litespeed (9); Slingshot (9); Specialized (3); Kestrel (2); Cervelo (1); FELT (1); Trek (2)
Mentioned: 39 Post(s)
Tagged: 0 Thread(s)
Quoted: 435 Post(s)
Liked 3,457 Times
in
997 Posts
Frames and Framebuilding (1970-1979) Frame Design and Building Practices in 1973
__________________
WTB: Slingshot bicycle promotional documents (catalog, pamphlets, etc).
WTB: American Cycling May - Aug, Oct, Dec 1966.
WTB: Bicycle Guide issues 1984 (any); Jun 1987; Jul, Nov/Dec 1992; Apr 1994; 1996 -1998 (any)
WTB: Bike World issue Jun 1974.
WTB: Slingshot bicycle promotional documents (catalog, pamphlets, etc).
WTB: American Cycling May - Aug, Oct, Dec 1966.
WTB: Bicycle Guide issues 1984 (any); Jun 1987; Jul, Nov/Dec 1992; Apr 1994; 1996 -1998 (any)
WTB: Bike World issue Jun 1974.
#2
Bike Butcher of Portland
Join Date: Jul 2014
Location: Portland, OR
Posts: 11,633
Bikes: It's complicated.
Mentioned: 1299 Post(s)
Tagged: 0 Thread(s)
Quoted: 4678 Post(s)
Liked 5,793 Times
in
2,280 Posts
Interesting that the author advised against "tiddly bits" brazed in the middle of thin wall tubing. At the time brass (bronze) brazing was the medium used, requiring a fairly high temperature, so tubing was easily "overcooked". From his description of "very tricky fluxes" for silver brazing, I can only guess that the flux I use today was not available BITD.
__________________
If someone tells you that you have enough bicycles and you don't need any more, stop talking to them. You don't need that kind of negativity in your life.
If someone tells you that you have enough bicycles and you don't need any more, stop talking to them. You don't need that kind of negativity in your life.
#3
Senior Member
Join Date: Jan 2004
Location: Madison, WI USA
Posts: 6,153
Mentioned: 50 Post(s)
Tagged: 0 Thread(s)
Quoted: 2362 Post(s)
Liked 1,749 Times
in
1,191 Posts
I was just amused by the reference to top-end bikes as being "multi-hundred-dollar".....
#4
Randomhead
Join Date: Aug 2008
Location: Happy Valley, Pennsylvania
Posts: 24,392
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 4 Post(s)
Liked 3,690 Times
in
2,513 Posts
In 1973, a paramount was just over $400. Too lazy to check an inflation calculator, but I think that's less than $2k
#5
Senior Member
I didn't see it mentioned in the article but can someone comment on the virtues/vices of hearth brazing vs. torch brazing? I think it's obvious that hearth brazing requires pinning as opposed to fixturing, but is one method of heat application better for the tubes/joints than the other?
#6
Senior Member
Join Date: Oct 2014
Location: Portland, OR
Posts: 12,902
Bikes: (2) ti TiCycles, 2007 w/ triple and 2011 fixed, 1979 Peter Mooney, ~1983 Trek 420 now fixed and ~1973 Raleigh Carlton Competition gravel grinder
Mentioned: 129 Post(s)
Tagged: 0 Thread(s)
Quoted: 4802 Post(s)
Liked 3,922 Times
in
2,551 Posts
#7
Randomhead
Join Date: Aug 2008
Location: Happy Valley, Pennsylvania
Posts: 24,392
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 4 Post(s)
Liked 3,690 Times
in
2,513 Posts
I didn't see it mentioned in the article but can someone comment on the virtues/vices of hearth brazing vs. torch brazing? I think it's obvious that hearth brazing requires pinning as opposed to fixturing, but is one method of heat application better for the tubes/joints than the other?
#8
Senior Member
Join Date: May 2008
Location: Fredericksburg, Va
Posts: 9,579
Bikes: '65 Frejus TDF, '73 Bottecchia Giro d'Italia, '83 Colnago Superissimo, '84 Trek 610, '84 Trek 760, '88 Pinarello Veneto, '88 De Rosa Pro, '89 Pinarello Montello, '94 Burley Duet, 97 Specialized RockHopper, 2010 Langster, Tern Link D8
Mentioned: 73 Post(s)
Tagged: 0 Thread(s)
Quoted: 1607 Post(s)
Liked 2,216 Times
in
1,103 Posts
@daka - its about heat control - soak/cooling as it impacts material crystalline structure. It is material mechanical properties driven. Some materials don't like a high delta of temperature in short distances. The other advantage in preheating is the workman doesn't have to wait for the joint to heat up from ambient temperatures, improves production labor time.
__________________
Bikes don't stand alone. They are two tired.
Bikes don't stand alone. They are two tired.
#9
Senior Member
Join Date: Jan 2005
Location: Baltimore, MD
Posts: 5,370
Mentioned: 15 Post(s)
Tagged: 0 Thread(s)
Quoted: 2482 Post(s)
Liked 2,952 Times
in
1,677 Posts
#10
Randomhead
Join Date: Aug 2008
Location: Happy Valley, Pennsylvania
Posts: 24,392
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 4 Post(s)
Liked 3,690 Times
in
2,513 Posts
I was wrong, that paramount from 1973 would be about 2500
#11
Senior Member
Join Date: Dec 2015
Location: San Diego
Posts: 703
Bikes: 1978 Bruce Gordon, 1977 Lippy, 199? Lippy tandem, Bike Friday NWT, 1982 Trek 720, 2012 Rivendell Atlantis, 1983 Bianchi Specialissima?
Mentioned: 11 Post(s)
Tagged: 0 Thread(s)
Quoted: 345 Post(s)
Liked 174 Times
in
106 Posts
And, who was this southern California craftsman?
#12
Senior Member
Join Date: Jun 2006
Posts: 20,305
Mentioned: 130 Post(s)
Tagged: 0 Thread(s)
Quoted: 3464 Post(s)
Liked 2,828 Times
in
1,995 Posts
One of the bike magazines did an article on Holdsworth, there was an image of hearth brazing a seat tube to a bottom bracket. That was the only image of that. the fire bricks were placed so the only items I could see brazes that way would be that, the fork crown to steerer, and maybe the chainstays to the dropouts.
#13
Senior Member
Join Date: Jun 2006
Posts: 20,305
Mentioned: 130 Post(s)
Tagged: 0 Thread(s)
Quoted: 3464 Post(s)
Liked 2,828 Times
in
1,995 Posts
At the time, Art Stump, Freddy Parr, and Jim Holly were the one man shows, G P Wilson, but he built very few. And Hood, again very few.
Freddy was an early experimenter is oversized tubes on Sprint bikes.
A bit later Brian Baylis / Mike Howard as Wizard.
Freddy was an early experimenter is oversized tubes on Sprint bikes.
A bit later Brian Baylis / Mike Howard as Wizard.
#14
Senior Member
Join Date: Dec 2015
Location: San Diego
Posts: 703
Bikes: 1978 Bruce Gordon, 1977 Lippy, 199? Lippy tandem, Bike Friday NWT, 1982 Trek 720, 2012 Rivendell Atlantis, 1983 Bianchi Specialissima?
Mentioned: 11 Post(s)
Tagged: 0 Thread(s)
Quoted: 345 Post(s)
Liked 174 Times
in
106 Posts
Kieth Lippy? Bill Holland? I’m pretty sure Lippy used silver. Just curious. As much as I enjoy reading these articles, I’m struck by how little they actually say considering how long they are. That reference is useless without a name, then and now.
#15
Randomhead
Join Date: Aug 2008
Location: Happy Valley, Pennsylvania
Posts: 24,392
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 4 Post(s)
Liked 3,690 Times
in
2,513 Posts
One of the bike magazines did an article on Holdsworth, there was an image of hearth brazing a seat tube to a bottom bracket. That was the only image of that. the fire bricks were placed so the only items I could see brazes that way would be that, the fork crown to steerer, and maybe the chainstays to the dropouts.
#16
framebuilder
I didn't see it mentioned in the article but can someone comment on the virtues/vices of hearth brazing vs. torch brazing? I think it's obvious that hearth brazing requires pinning as opposed to fixturing, but is one method of heat application better for the tubes/joints than the other?
After assembling the front triangle on the cast iron fixture, the tubes/lugs were both spot brazed and pinned together. The unit was taken over to the hearth table where the frame was hung over and surrounded by fire bricks. The natural gas nozzle was huge and the flame was augmented by oxygen from a squirrel cage blower. Both head lugs would be done at one time. Of course this giant flame heats the tubes fairly far up from the lugs. I would hold the brass rod in a holder to keep my hand away from all the heat. The flame didn't take much movement on my part and the hot metal would easily absorb the brass by capillary action.
The good news is that hearth brazing applies heat evenly so the frame is not thrown out of alignment like might happen by doing one part before another. However neither was it perfect because we would always have to make adjustments on the alignment table before doing another joint. Andrew (Ellis Briggs journeyman builder at the time) quit doing hearth brazing in favor of doing it all by oxyacetylene torch. The problem was that the lug shorelines had to be touched up with an OA torch after hearth brazing so he figured why have a 2 step process when it could all be done at one time.
When I came back to the States I immediately started brazing with silver with an oxyacetylene torch. It melts at 400 degrees lower temperature - which is an obvious advantage to both tube and alignment. Now I use propane instead of acetylene. The oxygen is supplied with an oxygen concentrator (the machine that normally supplies oxygen to damaged lungs).
Likes For Doug Fattic:
#17
1/2 as far in 2x the time
Join Date: Nov 2013
Location: Northern Bergen County, NJ
Posts: 1,746
Bikes: Yes, Please.
Mentioned: 13 Post(s)
Tagged: 0 Thread(s)
Quoted: 499 Post(s)
Liked 285 Times
in
222 Posts
I went to learn how to build frames at Ellis Briggs Cycles in Shipley, West Yorkshire in 1975. Compared to most other UK builders I visited, their equipment was more clever and sophisticated. Their fixture was based on a cast iron alignment table. They brazed the major joints by hearth brazing but while I was there switched over to doing them with a oxyacetylene torch. The very 1st frame I made was hearth brazed.
After assembling the front triangle on the cast iron fixture, the tubes/lugs were both spot brazed and pinned together. The unit was taken over to the hearth table where the frame was hung over and surrounded by fire bricks. The natural gas nozzle was huge and the flame was augmented by oxygen from a squirrel cage blower. Both head lugs would be done at one time. Of course this giant flame heats the tubes fairly far up from the lugs. I would hold the brass rod in a holder to keep my hand away from all the heat. The flame didn't take much movement on my part and the hot metal would easily absorb the brass by capillary action.
The good news is that hearth brazing applies heat evenly so the frame is not thrown out of alignment like might happen by doing one part before another. However neither was it perfect because we would always have to make adjustments on the alignment table before doing another joint. Andrew (Ellis Briggs journeyman builder at the time) quit doing hearth brazing in favor of doing it all by oxyacetylene torch. The problem was that the lug shorelines had to be touched up with an OA torch after hearth brazing so he figured why have a 2 step process when it could all be done at one time.
When I came back to the States I immediately started brazing with silver with an oxyacetylene torch. It melts at 400 degrees lower temperature - which is an obvious advantage to both tube and alignment. Now I use propane instead of acetylene. The oxygen is supplied with an oxygen concentrator (the machine that normally supplies oxygen to damaged lungs).
After assembling the front triangle on the cast iron fixture, the tubes/lugs were both spot brazed and pinned together. The unit was taken over to the hearth table where the frame was hung over and surrounded by fire bricks. The natural gas nozzle was huge and the flame was augmented by oxygen from a squirrel cage blower. Both head lugs would be done at one time. Of course this giant flame heats the tubes fairly far up from the lugs. I would hold the brass rod in a holder to keep my hand away from all the heat. The flame didn't take much movement on my part and the hot metal would easily absorb the brass by capillary action.
The good news is that hearth brazing applies heat evenly so the frame is not thrown out of alignment like might happen by doing one part before another. However neither was it perfect because we would always have to make adjustments on the alignment table before doing another joint. Andrew (Ellis Briggs journeyman builder at the time) quit doing hearth brazing in favor of doing it all by oxyacetylene torch. The problem was that the lug shorelines had to be touched up with an OA torch after hearth brazing so he figured why have a 2 step process when it could all be done at one time.
When I came back to the States I immediately started brazing with silver with an oxyacetylene torch. It melts at 400 degrees lower temperature - which is an obvious advantage to both tube and alignment. Now I use propane instead of acetylene. The oxygen is supplied with an oxygen concentrator (the machine that normally supplies oxygen to damaged lungs).
Before the pandemic, I used to think about getting an oxygen concentrator, for the couple times a year I get lung infections, having had severe asthma for many years. Obviously now is not the time, but propane and a concentrator would be sufficient to not need an oxy/acyetelene unit? That's pretty cool.
Best regards, Eric
__________________
I seem to have lost what little mind I had left before this all started.
I seem to have lost what little mind I had left before this all started.
#18
framebuilder
Doug,
Before the pandemic, I used to think about getting an oxygen concentrator, for the couple times a year I get lung infections, having had severe asthma for many years. Obviously now is not the time, but propane and a concentrator would be sufficient to not need an oxy/acyetelene unit? That's pretty cool.
Best regards, Eric
Before the pandemic, I used to think about getting an oxygen concentrator, for the couple times a year I get lung infections, having had severe asthma for many years. Obviously now is not the time, but propane and a concentrator would be sufficient to not need an oxy/acyetelene unit? That's pretty cool.
Best regards, Eric
M&M Medical in Beaverdale, PA refurbishes concentrators for general use sale. A Devilbiss model 525 costs $300 with a 3 year warranty. I just called them last week and they have them back in stock. That model is my favorite because it has more output that other manufacturer's 5 liter per minute models. Some of my frame building class students have gotten concentrators on Craigslist or wherever for less but of course that is a matter of luck. They are rare during the pandemic because more concentrators are needed for damaged lungs.
#19
1/2 as far in 2x the time
Join Date: Nov 2013
Location: Northern Bergen County, NJ
Posts: 1,746
Bikes: Yes, Please.
Mentioned: 13 Post(s)
Tagged: 0 Thread(s)
Quoted: 499 Post(s)
Liked 285 Times
in
222 Posts
Yes propane combined with an oxygen concentrator works great. BBQ propane tanks can be bought zillions of places at all hours. Neither is its transportation and sale restricted like acetylene. It isn't sooty either and much much cheaper. What makes propane work better for brazing frames are propane specific multipart tips. Paige Tools a source for jewelry makers listened to our pleas and made adaptors for their tips that work for Smith AW1A and Victor J-28 torch handles.
M&M Medical in Beaverdale, PA refurbishes concentrators for general use sale. A Devilbiss model 525 costs $300 with a 3 year warranty. I just called them last week and they have them back in stock. That model is my favorite because it has more output that other manufacturer's 5 liter per minute models. Some of my frame building class students have gotten concentrators on Craigslist or wherever for less but of course that is a matter of luck. They are rare during the pandemic because more concentrators are needed for damaged lungs.
M&M Medical in Beaverdale, PA refurbishes concentrators for general use sale. A Devilbiss model 525 costs $300 with a 3 year warranty. I just called them last week and they have them back in stock. That model is my favorite because it has more output that other manufacturer's 5 liter per minute models. Some of my frame building class students have gotten concentrators on Craigslist or wherever for less but of course that is a matter of luck. They are rare during the pandemic because more concentrators are needed for damaged lungs.
I will keep collecting my bits
Thanks again, Eric
PS I hated those stringy bits of black stuff floating about. Forgotten all about them.
#20
Randomhead
Join Date: Aug 2008
Location: Happy Valley, Pennsylvania
Posts: 24,392
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 4 Post(s)
Liked 3,690 Times
in
2,513 Posts
Doug, when they were hearth brazing, how did they do the rear triangle?
Good to hear than M&M has concentrators, maybe I'll buy one
Good to hear than M&M has concentrators, maybe I'll buy one
#21
framebuilder
Oxygen concentrators are great. It is an endless supply of oxygen that doesn't require refill trips or expense. My tanks always seemed to run at 4:59 on Friday afternoon. It does take a couple of minutes for the concentrator to purge its holding bladder and hose lines with almost pure oxygen. That means I turn it on when I start fluxing the joint. While some of my students have found used concentrators for under $100, that is pure luck. A local student has been watching Craigslist for a whole year without any luck finding one that cheap. Most personal sales cost at least $300 or more. He figured getting a refurbished one with a 3 year warranty from M&M made more sense. Ask for a Devillbiss model 525. I also scored a couple of almost brand new Invacare Platinum concentrators and they work fine with normal tips but don't have as much output for when I want to use a rosebud.
Likes For Doug Fattic:
#22
Shifting is fun!
Join Date: Aug 2009
Location: South Holland, NL
Posts: 11,000
Bikes: Yes, please.
Mentioned: 279 Post(s)
Tagged: 0 Thread(s)
Quoted: 2196 Post(s)
Liked 4,594 Times
in
1,764 Posts
Interesting to read about the American take on what constitutes a top-end bike. In my area there would have been only one question: does it win races? I don't think anybody here was interested in ornate lug filing or interesting-looking dropouts. A top-end bike was a race-winning bike, and such a bike needed to be fast and reliable. And cheap, if possible.
#23
Full Member
Join Date: Aug 2019
Location: Albuquerque
Posts: 227
Bikes: 1st Track bike: 1978 Speedwell titanium 1st Road bike: 2001 Independent Fabrication Crown Jewel
Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quoted: 97 Post(s)
Liked 116 Times
in
65 Posts
Fascinating article - thanks for sharing. I learned a lot. Its interesting he states that more than half the way a frame rides is due to the technical skill of the builder. I don't know how he determined this performance ratio, but I do think that tubes make a huge difference. All my Columbus frames feel very different than the Reynolds 531 I've got and the Reynolds straight guage frame I had felt so dull in comparison to the double-butted Reynolds frame, I got rid of it.
Given the choice of a bike from competent builder with top quality steel or a master builder with plain guage - I'd go with the former!
Given the choice of a bike from competent builder with top quality steel or a master builder with plain guage - I'd go with the former!