le bici di jaco

I am trying to determine the year Columbus introduced "SL" tubing for bike framebuilding. Also, I would like to know when Columbus first used a reinforced steerer tube with the 5 ridges. I am trying to determine the approx. earliest year of a frame; possibly 60s?

cb400bill

Thread moved from Framebuilders to Classic & Vintage.

juvela

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Buongiorno Jesper & welcome to the forum!


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GhostRider62

70's for sure if you believe my eyeballs

1935...???

https://www.bikeforums.net/8638958-post7.html

unterhausen

It's interesting to me that the Columbus website doesn't mention the history of SL at all.

The other thread doesn't seem to show anything that actually says, "SL," or maybe I'm not reading it right. On edit: reading further in that thread confirms the stuff from 1935 didn't say anything about SL. I think before the late '70s it might have just been "columbus" and you pick your tube thickness. Might be easier to find a frame of known provenance with an SL sticker

GhostRider62

Agree. That is why I put...??

Interesting historical tidbit. 531 was around back then, so, similar dates for Columbus...??

unterhausen

I think SL was just branding, so it's quite possible they introduced it much later. The tubing company was spun off in the '70s, so they may have decided they needed more branding about then. As opposed to earlier where the tubing existed in the material and thickness of SL, but wasn't branded as such.

P!N20

So my understanding is the tubing that was introduced in 1935 had pretty much the same properties as SL, but it wasn’t until the 1970’s that it was labeled as such.

Some good info here: https://www.bikeforums.net/classic-v...sl-tubing.html

This bit in particular:

bikingshearer 

Metallurgically speaking, SL, SP, SLX and SPX are all the same as what in the 1960s was stickered simply as "Columbus" tubing. The same tubing probably goes back into at least the 1950s and maybe before that, although I don't know that for sure. SL and SLX have thinner walls than SP and SPX (the difference is 0.1mm in most places). SLX and SPX was the same tubing with the addition of the helical reinforcements. I am 95% sure that PL and PS were also the same thing but designed and intended for track ("pista") frames.

I know that Reynolds 531 dates from the 1930s and was used to make the part of the Spitfire framing that held the Rolls Royce Merlin engine in place. Columbus was certainly in business back that far, but I don't know when they came up with the specific alloy that eventually came to be known as SL, SP, etc. Their website is not exactly a model of clarity on this, although it is at pains to point out that a lot Columbus' production before WWII went into furniture making.

sincos

Was that tubing Cyclex? 4130? Hi-tensile? How is Cyclex different from 4130, anyway? (I've heard Cyclex has a trace of vanadium, but have no idea if that's correct).

JohnDThompson 

My early 80s Columbus catalog claims 1930 as the start date for the company. It doesn't specifically mention when "SL" came on the market, but it's reasonable to assume around the same time. SL, SP, PL, and PS tubing were all the same alloy, just drawn to different thicknesses and shapes. Columbus tubing decals didn't distinguish between these versions until the mid-1980s.

https://www.os2.dhs.org/~john/catalog...mbus-tubes.pdf

Doug Fattic 

Just to add to the confusion, SL and SP I believe were heat treated. This is what made that tubing different from AL. When I was at the NY bike show in the middle to late 70's (before they stopped having it in NY), Columbus had a booth with a video of them making their tubing. After the double butting process, they showed a black screen with white letters saying "secret process". The surface of SL and SP has a bluish to golden hue. Their cheaper AL tubing with the same specs is just dull gray. I believe their "secret process" is the result of some kind of heat treatment. It is also probably when they started marketing their tubes as SL and SP. Of course that is just a guess on my part. I started building frames in 1975 and I think I remember Columbus having the SL and SP designation then.

T-Mar

I don't buy into the belief that Columbus has been producing SL since the 1930s. While pre-1970 Columbus catalogues are rare, threre is an extant 1950 Bozzi catalogue with spec sheets for Falck and Mannesmann-Dalmine, who were Columbus' two biggest Italian rivals. Neither offered SL gauge tubesets at the time. Their lightest sets were basically SP equivalents. Also, a 1950s Reynolds catalogue shows an SL gauge tube available but only as a top tube. The larger diameter and heavier stressed down and seat tubes are at least SP gauge. I don't think any of these three companies would have given Columbus a two decade head start without responding. My basic feeling is that the roads of the era were considered too rough to warrant tubesets this light.

As for butted steering tubes with helical reinforcements, the 1950 Bozzi catalog shows one but doesn't mention the brand.

T-Mar

Aelle used a different steel alloy than SL and SP, which accounts for the difference in appearance. The chromium content in the SL/SP alloy gives it a shinier appearance and some corrosion resistance.

As for heat treatment, it's standard practice to anneal cold drawn tubes between drawing operations, to restore ductility and prevent brittle fractures. This would have been done with both Aelle and SL/SP.

le bici di jaco

Thanks to all for the input. I had essentially found the same information, albeit vague, regarding their use of Columbus tubing for aircraft, race cars, motorcycles, and furniture; with just a mention that Columbus was also making bike tubes. One would assume the name "Cyclex" had some significance regarding tubes manufactured specifically for bikes. Since "SL" (et al.) tubes are made with that alloy formulation, and Columbus was already making butted tubes; I assume that the "SL" dimensioned tubes came into being around the same time, regardless of whether it was designated as "SL" or not, as the onset of Columbus developing that "Cyclex" alloy formulation for use primarily for bike frames. I have not found any reference regarding a "Cyclex" year of introduction in any timeline.
My query is in regards to a frame I got from an honest seller who could not guarantee that the frame was Columbus tubing (fork has Columbus dove stamp on tube and "rifling"), nor that the frame, which has Vicini decals, is even made by that brand bike company (frame repainted at least once). The frame feels too heavy to be all "SL", possibly only the main tubes are "SL". Smaller frame (55cm) so I doubt that it is "SP" tubing; frame is far too early (I assume 1960s to early 1970s, no braze-ons anywhere) for "SLX/SPX" variants.

T-Mar

Cyclex was developed and patented by Columbus in 1986. It made it's commericial appearance in late 1987 for the 1988 model year in the MS, TSX, SLX/SPX. SL/SP, and Tandem CM tubesets. Pro teams were likely testing it in 1987. Basically, it was a modified CrMo alloy with higher tensile strength and hardness.

You should post pictures of your frame. There could be other characteristics that may provide an indication of the age.

tendency

1927. it's old and slow - avoid in a bike.

le bici di jaco

Sorry, I do not understand your meaning or reference.


T-Mar Was Cyclex a name for a new steel alloy formulation used for '80s tubes, or was it the same alloy formulation used in '70s and earlier tubes ("SL" tubes and others), but just given a fancy name in the '80s? The previous owner was dubious about everything regarding the frame; thus, the reason for selling it fairly cheap ($75).

I will post photos when allowed.

FelixScout

The late Sheldon Brown disagrees with you: https://www.sheldonbrown.com/org/ranger.html

T-Mar

Cyclex was a new/revised forumlation of Columbus' traditional CrMo alloy. The changes were significant enough to warrant a 1986 patent. If it was the same alloy as used in the 1970s, why wait until the mid-1980s to get a patent on it? After Cyclex was introduced, Columbus continued to used their traditonal CrMo alloy on some lower tubesets, such as Cromor.

As for photos, you can upload them now. They won't attach to your post but they will upload to gallery album, under you user name. Then, myself or another member could post the link to the photos or post them directly in this thread.

repechage

in 1974, one of the shop managers bought a number of Columbus tube sets, SL, SP, PL, PS
( which I thought was cool as the chainstays were 24mm then swaged down for the bottom bracket shell sockets. I can confirm the blue to bronze discoloration. Think 60’s motorcycle exhaust pipes after a time,

in 1975, a Carlsbad Masi could be ordered for a $25 upcharge the frame made with Columbus tubes, if you knew to ask.
smart choice as Mario Confente built those.
he offered that brazing Columbus was a bit more work than Reynolds, heat control was more important, Reynolds was more forgiving.
someone out there has one made of Ishiwata tubes, Mario stated he liked them.

Sluggo

Assuming that the SL/SP alloy is close to 4130, there must be some heat treating. As-drawn 4130 is only 480 MPa yield and 655 Mpa UTS; Columbus SL/SP is 735 yield and 835 UTS. Increasing the strength while retaining ductility and brazeability would be the tricky part, and it makes sense that the temperatures and durations of quench and temper would be a secret process. BTW, as-quenched 4130 can be as strong as 1325 yield/ 1600 UTS if you want to make a knife from it.

cbrstar

I can't seem to find it, but I believe I read somewhere that when he registered the name Columbus, he also registered Tenax and Aelle in the early 1930's. Tenax from other pages on here sounds like SL/SP but slightly different?