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Black_Moons
02-01-2010, 12:47 PM
Whoopse. Was trying to 16TPI thread upside down.. away from a low shoulder... lathe was spining forward though and did'nt notice before engageing the halfnut. Ended up cold forming a 2 turn thread into aluminum with the back of my latest HSS cutting bit! glad I did'nt put much radius on it and a good amount of relief! and the shoulder wasent that big... Intrestingly it cut... err, Displaced a very deep thread that looks sorta ok (Except ruining the first turn), allthough the crest is totaly ragid and way higher then the OD of the origional metal! I really should'nt be using my lathe with so little sleep -_-;

Was intresting however. I did'nt think it would displace metal so easily and with such a reasonable finish for such a deep displacement in one go. Sure incressed the OD too with nowhere for that metal to go but up.

Carld
02-01-2010, 12:53 PM
:eek: opps, I bet you were grabing handles and/or switches real fast. :D

I sure can relate to that :o .

lakeside53
02-01-2010, 01:45 PM
Of course, nobody else has ever done that:D


Yesterday I was making very aggressive test cuts in 4 inch diameter chunk of some mystery 4xxx alloy. I accidentally hit the power feed lever at the shoulder from turn to face (the interlock must have not been set correctly...). Damn... plowed a 3/8 inch V into the metal and snapped off the big insert (DNMP). Then to add insult - as I was inspecting the result a nasty piece of swarf jumps out and deliberately cuts my finger.:mad:

Could have been worse... and a good reminder that machines, sorry.. I mean "my own stupidity", can hurt me.

Evan
02-01-2010, 02:16 PM
My South Bend motor switch is designed to weed out dyslexics. It sits on top of the head stock and the lever moves right to go forward when you are threading to the left and left to go right. Even after many years of using it I have moments of complete paralysis when I am about to switch it on, especially since I don't use a threading dial.

The Artful Bodger
02-01-2010, 04:09 PM
My South Bend motor switch is designed to weed out dyslexics. It sits on top of the head stock and the lever moves right to go forward when you are threading to the left and left to go right. Even after many years of using it I have moments of complete paralysis when I am about to switch it on, especially since I don't use a threading dial.


I am sure the Chinese makers of my lathe did not do it on purpose but I find the feed select handle on the saddle somewhat confusing. 'Up' engages carriage travel and 'Down' engages cross feed, for some reason I always feel it should be the other way around!:rolleyes:

John Stevenson
02-01-2010, 04:20 PM
Of course, nobody else has ever done that:D




No never, ever ;) can't see how anyone could be so stupid, ...........exit stage left , ........whistling slightly off tune.

.

Lew Hartswick
02-01-2010, 05:12 PM
I am sure the Chinese makers of my lathe did not do it on purpose but I find the feed select handle on the saddle somewhat confusing. 'Up' engages carriage travel and 'Down' engages cross feed, for some reason I always feel it should be the other way around!:rolleyes:
Why should it be the other way? The Clausing/Metosa's at school
are just like that. (8 of them). The big problem I have with the kids
is getting them to just use an open hand to return the lever to "OFF".
They seem to want to GRAB it with their whole hand and then way
too often take it past center and ruin a project.
...lew...

The Artful Bodger
02-01-2010, 05:33 PM
Why should it be the other way? ...

No reason, it just seems it should be..:D