On 3/19/2018 8:09 PM, John B. wrote:
On Mon, 19 Mar 2018 12:43:45 -0700, Jeff Liebermann
wrote:

On Mon, 19 Mar 2018 19:47:27 +0100, Emanuel Berg
wrote:

Jeff Liebermann wrote:

What do you think guys, maybe this one is
a good choice?

https://www.youtube.com/watch?v=jML8nVSntuE

A good choice for doing what?

In another thread was the question,

I don't read every thread.

how do they
cut aluminium tubes so that they fit together
before welding, e.g. the top and down tube to
the head tube? And the answer is a
milling machine (and not a press drill).

It's called "mitering":
https://www.google.com/search?q=mitering+bicycle+tubes
A mill with an tiltable head is probably the easiest way to do it.
I've watched the process, but have never done it myself. It can also
be done with a lathe. I don't know if a drill press will work,
probably not. Forget about using a tubing notcher. If the metal is
soft enough for a notcher to work, then it's not strong enough to
ride.

I'm sure the Luna is a good choice for
"doing it" only the person who has to pay for
it might disagree

I don't know anything about Luna mills. Mitering bicycle tubes does
not require fabulous precision. A Chinese benchtop mill could be used
if you're cheap or desperate. The accuracy is mostly in the jigs and
fixtures.

A file is accurate enough :-)


+1

Since I'm in the 'no two alike' frame repair business, I can
miter a top tube at both ends to length with a file faster
than the setup on a general purpose mill.

http://www.yellowjersey.org/gth8.jpg

If you're making a lot of frames to the same geometry, a
Marchetti & Lange machine is what you want, but that is not
Mr Berg.

--
Andrew Muzi
www.yellowjersey.org/
Open every day since 1 April, 1971