Easto EC 70 Seat Post

[A Muzi]

> "A Muzi" <[email protected]> wrote in message news:[email protected]...
> > -snip frame prep woes-

> > "Robin Hubert" <[email protected]> wrote in message
> > news:[email protected]...
> > > This is why I like selling titanium frames. When's the last time
you
> > > chased and faced one of those?

> > Yesterday afternoon. And I did have to take out material from the BB threads to get a cup in.

"Robin Hubert" <[email protected]> wrote in message
news:[email protected]...
> Yoink! I thought this wasn't possible without machine help <showing my
> ignorance> Anyone else?

Titanium cuts and files more easily than steel as anyone who's trimmed an MTB handlebar can attest.

The problem in machining is that titanium is sticky and stretchy. I know those are funny words for a
metal but the effect is that taps don't cut cleanly and the material drags against the "clearance"
behind the cutting edge.

That property, similarly to brass/bronze, leads quickly to broken taps/mills/drill bits . One needs
to watch the coolant/cutting oil and especially the feed/speed so the tool doesn't stick and break.
I often use a 5mm tap held snug but not tight in a cordless drill for clearing bottle bosses and
mudguard eyes. I would never try that in a ti frame as I could see a snapped tap being easy to do.
Even with a tap handle they stick sometimes.

In the case of BB taps, there's a lot of heat generated as the clearance behind the edge drags. We
use a lot of cuttig fluid but with a hand-powered tool we don't have to worry about breaking off a
34.8mm tap!

Head mills get very hot in ti again because you can't get a clean cut and the material drags behind
the edge. In a head tube you have to remove the tool occasionally to clear the swarf. We keep the
axis horizontal so we keep plenty of cool fluid across the cutting faces.

I suspect that ti takes more life out of my tool edges that steel but probably isn't as bad as the
occasional new guy who runs them on chromed faces.
--
Andrew Muzi http://www.yellowjersey.org Open every day since 1 April 1971

 

[Patrick Lamb]

On Wed, 15 Jan 2003 10:55:22 -0600, "A Muzi" <[email protected]> wrote:

>From: "Glhudson1" <[email protected]>
>> just curious why the retailer is responsible for frame prep and not the manufacturer of the
>> frame. anyone have any ideas on why that is?
>
>Because the dealer is the defacto quality control station for manufacturers, who cannot seem to (or
>will not) manage that function in-house.
>
>I recall when new car prep was similarly daunting, involving a lot of work and care. Auto
>manufacturers have taken an aggressive stance there, and deliver a more uniform product now than
>they did thirty years ago ( not that they are perfect, but generally cars are now driveable when
>delivered to the dealership, unlike bicycles).

I suspect Consumer Reports deserves the credit for that -- prepping the car was always a dealer
function, and they would ream American manufacturers when the dealer didn't do something right.
(Toys and Hondas were always perfect when they came on the lot, of course. -) But when Buycyclist is
busy shilling for the major makers, I can't see the same happening for bikes any time soon.

BTW, how come I'm still getting charged more for dealer prep when they don't do nearly as much now
as 30 years ago?

>In the case of a premium frameset, the dealer should measure threads and bores, correct as
>necessary and check alignment before sale. Many small errors are righted on nearly every unit. No
>other industry would stand for that level of error, IMHO. Can you imagine if every electronic
>device at Radio Shack needed dealer prep?? Or a bookstore gluing bindings on new books?

Yeah, I've bought enough books that fell apart after 3-6 months that I'd change my shopping habits
if a bookstore would do it right the first time out the door.

Pat