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Strong Newsletter... news..
 

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Sparky
Joined: 08 Dec 2003
Posts: 17650
Location: Portland, OR

3/14/20 12:06 PM

Strong Newsletter... news..

Carl is dropping steel; ti only going forward. And the Pursuit line of carbon of course.


quote:
End of an Era
I recently finished what I expect will be the last steel frame I will make.


https://mailchi.mp/b9cdf17e5947/end-of-an-era?e=7d058174b9

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dfcas
Joined: 11 Jan 2004
Posts: 2633
Location: hillbilly heaven

3/14/20 8:12 PM

Surely a steel tubeset is a lot cheaper than a ti tubeset,, and it seems that cutting tools would need to be sharpened/replaced a lot more and faster with ti. Maybe its the cost of being in business and labor that drives custom frame prices?

I hope I don't need to run my BB tap/facing set thru the Lynskey ti I have inbound. Sparky how has the prep been on the Lynskeys you've had?

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Sparky
Joined: 08 Dec 2003
Posts: 17650
Location: Portland, OR

3/14/20 8:23 PM

Perfect.

Carl had said once True Temper stopped producing tubes it changes this a lot.

He had raised his Steel to same price as Ti, now this.

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KerryIrons
Joined: 12 Jan 2004
Posts: 3038
Location: Midland, MI

3/15/20 9:27 AM

Frame prep


quote:
how has the prep been on the Lynskeys you've had?


My Lynskey R 450 and before that my Litespeed Vortex (both built by Lynskey family) have been perfect in threading and alignment. Solid as a rock and no issues. They have the skills to build it right.

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Brian Nystrom
Joined: 26 Jan 2004
Posts: 4581
Location: Nashua, NH

3/16/20 5:59 AM

While Ti is certainly harder on cutting tools than steel, you're not going to wear out quality tools by chasing and facing a single bottom bracket. That's probably a moot point, as the likelihood of needing to do so is about zero. You're not dealing with some low-end supplier trying to produce frames a cheaply as possible.

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Craig
Joined: 12 Jan 2004
Posts: 579

3/17/20 10:25 AM

It's a bit of a misconception that titanium is "hard". While alloys etc will yield a broad range of results and your mileage will vary, titanium can actually be softer than steel https://www.thomasnet.com/articles/metals-metal-products/steel-vs-titanium-strength-properties-and-uses/ in many applications. The chart on that web page shows steel with a Brinell hardness of 121 and titanium with a Brinell hardness of 70, though it's likely both numbers are higher in bicycle applications (it's unclear what alloy of steel is being discussed, but it's almost definitely pure titanium, bicycles being 3/2.5 or 6/4 alloys, both being harder than pure titanium).

But as Brian suggests, there's a slim to nil chance a frame will leave Lysnkey without being prepped for building already.

The cost of tubes in a bike frame is actually a relatively small part of the overall cost. Yes, titanium costs more, but the labour time makes up a bigger part, and good paint isn't cheap. The cost of a professional paint job (plus shipping to and from the painter) will quickly offset the difference in tubeset costs meaning it's easy to understand why a steel bike would cost as much as a titanium bike these days.

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Brian Nystrom
Joined: 26 Jan 2004
Posts: 4581
Location: Nashua, NH

3/19/20 12:24 PM

The issue with Ti and tools is not that it's hard, it's that it's springy, sticky and it work hardens as you cut it. It creates a lot of friction and heat, which are the enemies of cutting tools

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Sparky
Joined: 08 Dec 2003
Posts: 17650
Location: Portland, OR

3/19/20 12:36 PM

Elaine's Dad was a Rolls Royce Machinist in UK, then had two shops in the US since the 60s he had jobs.

He told me 25 years ago his least fav activity was tapping small threads in Titanium outta every other task he ever preformed. Gummy IIRC was the term he used. Sounds like maybe commercially pure material if I am guessing...

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dddd
Joined: 11 Jan 2004
Posts: 3292
Location: NorCal

3/23/20 1:21 AM

"...Gummy IIRC was the term he used..."

Must be a common term for machinists to use when dealing with difficult metals.

When I was designing high-pressure hydraulic manifolds at NASA for the UH-60 large-rotor test apparatus in the Ames wind tunnel, the machine shop guys used the same term "gummy" to describe 317 stainless steel. They complained of the difficulty machining the tapered seats deep inside of the threaded ports of the manifolds. Making matters critical was the lack of rigidity of the extended tooling, which tended to cause chatter at the cutting speeds that this particular material required.

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KerryIrons
Joined: 12 Jan 2004
Posts: 3038
Location: Midland, MI

3/23/20 9:38 AM

Gummy

A machinist I used to work with many years ago had the same description for 316 stainless: "not hard, but hard to machine."

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dddd
Joined: 11 Jan 2004
Posts: 3292
Location: NorCal

3/23/20 9:57 PM

Titanium's combination of relatively low flexural modulus with relatively high strength means that it can tend to move out of the way of a cutting edge.
So a more aggressive angle of attack against a strong material using a sharper cutter angle causes higher stress and wear on the cutting edge.

Where the tooling can be made rigid (as with a bb shell having a 1.37" inside diameter), the cutting to precise tolerances is a piece of cake once the cutter edge shape and surface speed are optimized for the material. It still might present a higher wear rate than when cutting steel, or at least require more-frequent sharpening (not quite the same thing), but repeatability and tool sharpening frequency can be very consistent procedural details that I would expect a good framebuilder to have under a good degree of control with accurate dimensions resulting.

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KerryIrons
Joined: 12 Jan 2004
Posts: 3038
Location: Midland, MI

3/25/20 8:44 AM

Expertise

The challenges of Ti machining and fabrication are why Litespeed was such a dominant force back in the 1990s. They came from doing aerospace fabrication and manufacture and so had all the in-house skills and tooling ready to go. All they needed was somebody to show them what a good geometry looked like (can you say Eddy Merckx?) and dial in the needed stiffness and they blew everybody out of the water until CF technology matured.

Interesting to realize that the Ti and CF "waves" in the bike biz both came right out of the aerospace industry and the end of the cold war.

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rickhardy
Joined: 11 Jan 2004
Posts: 1469
Location: Needham outside of Boston - the hub of the universe

3/26/20 12:07 PM

Article

https://redkiteprayer.com/2018/11/the-pull-frame-builder-carl-strong/

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KerryIrons
Joined: 12 Jan 2004
Posts: 3038
Location: Midland, MI

3/27/20 8:39 AM

Editing

The article starts out by saying that Strong is known for "titanium road and gravel frames he makes from titanium." Some editing required :)

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