Heavy cutting U tube

[morrisman]

Hi

Can somebody explian the dynamics of this video ?

The depth of cut and the RPM of the spindle .

I imagine only a larger rigid lathe would be capable of this heavy cut ? :?

14" Hendey Lathe - YouTube

Mike

[Ueee]

Wow that's slow! An explanation would be great.
Ewan

[Bryan]

The stop-start thing is a problem with the camera or something. It does appear to be turning slow. Could be hard material. It's not that big a cut for a proper lathe.

Edit: The jerkiness was a browser issue. Please disregard.

[Abratool]

Mike
Even with an old lathe that may be a bit worn, turning between centres, at slow speed, provides a very rigid set up, reducing the possibilty of vibration, that might come from bearings & poor fitting chuck mounts & the like.Anyway thats been my experience.
The slow speed is perhaps because its a tough steel & the use of HSS toolbits, & an old lathe, flat belt, age, worn bearings ?
Before the popular use of HSS the use of carbon steel hardened toolpieces required slow speeds, but I do not think this is the situation in this video
All the best Mike
regards
Bruce

[Abratool]

Mike
Heres another thought..
The lathe is on its slowest speed in backgear.
Out of backgear perhaps the lathe does not have enough torque & belt slip is a problem?
Then again in direct drive with the large driving dog, vibration starts?
Or the bloke has plenty of time on his hands & just like to prolong the job & enjoy it :2tsup:
Nothing wrong with that, I have the same problem :rolleyes:
regards
Bruce

[morrisman]

OK Bruce

Would it be possible to take a cut like that in mild steel, with a typical 9" lathe like some of us use ? The slowest my lathe turns is around 60 rpm .

Mike

[Abratool]

Mike
When I viewed this, the immediate thought was "Thats not a deep cut, particularly with a lampost style toolpost.
I would say without any hesitation that your 9 inch lathe could do the same or even better. Cannot remember, is it a Hercus flat belt 9 Inch ?
The other thing with "older thinking" was deep roughing cuts at slow speeds, & good tool life between sharpenings.
Its amazing what metal can be removed with a small lathe at lower speeds.
With my 260 Hercus on 1" dia MS I can take 3/16" depth of cut easily, but its in backgear, plenty of torque, lovely to watch.
Perhaps give it a try.
regards
Bruce

[.RC.]

Yea that is not a deep cut..

Here is an old lathe taking a decent cut :)

25" Lodge & Shipley - YouTube

[aametalmaster]

Thats the difference when you have a bigger machine with some horsepower. I can take a good 3/8" + deep cut on my little South Bend but i need to run it in backgear to get the power. The time it takes to cut you could have made 3 passes at normal speed that equal the deep one...Bob

[morrisman]

Ok

I had a go at deep cutting in back gear .

Great results :2tsup: With back gear in, and 60 rpm . 3mm deep cuts are easy . Using a sharp roughing cutter , its like hot knife in butter . Rather slow feeds though. takes ages to traverse . Pics taken during the cutting

Im making the spindle here for the dividing head fixture .

BTW thats the cheap Chinese chuck in use

Mike

[aametalmaster]

Ok



Im making the spindle here for the dividing head fixture .

BTW thats the cheap Chinese chuck in use

Mike
More pics of your dividing head progress please. I started one but need to do a little more on it. I use those cheap china chucks and like them. I am buying a 14" 4 jaw for my big lathe...Bob

[morrisman]

More pics of your dividing head progress please. I started one but need to do a little more on it. I use those cheap china chucks and like them. I am buying a 14" 4 jaw for my big lathe...Bob

BOB

This is the dividing head project Dividing Head, Basic (http://www.homews.co.uk/page132.html)

[Abratool]

Mike
I bet you liked watching the cutting action.Something about metal curling off easily:wink:
Bruce

[Ueee]

Mike,
Could you take a pic of the cutting tool your using- just interested to see the angles.
Thanks
Ewan

[morrisman]

Ewan

The angles are forgiving . Not that critical

I think the secret is having the edge very sharp .

You want a minimun 2mm radius on the tip .

Also . The approach angle of the tool should be less than 90 degrees . The cutting edge of the tool, should not be square on to the work piece eg 90 degrees . The wider cutting edge on the work means less strain on the tool . I think ? You can see in the last pic, the tool cutting edge angle ( approah angle ) in relation to the work piece .

Mike

[Ueee]

Mike,
I'm guessing thats 3/8 or 1/2 HSS?

Ewan

[morrisman]

Mike,
I'm guessing thats 3/8 or 1/2 HSS?

Ewan

It's 3/8" HSS Ewan

MIKW