Parting on the Lathe

[EdK]

(12-09-2013, 09:05 AM)TomG Wrote:

(12-08-2013, 10:08 AM)EdK Wrote: Tom,

What brand is that cutting oil you used? It's getting hard to find sulfur based cutting oil.

Ed

Ed,

Dark sulphonated cutting oil is available at Home Depot.

Tom

Strange, I've looked numerous times at Home Depot and they never had any. Now they show they stock it.

Thanks for the info.

Ed

[PixMan]

(12-09-2013, 12:41 PM)awemawson Wrote: My 'preferred' width is 2 mm using a Sandvik 151.2-21-20 parting insert holder, and I must confess to pushing too far sometimes on larger diameter stock as I'm too mean to lose more off the stock with a wider blade

Did you know that you can also use Valenite VSG 2.0 N 20 and VSG N2.24 N 20 inserts in that Sandvik Coromant holder (or blade)? Keep an eye out on eBay for deals on those too, could be had cheaper!

[f350ca]

Ridgid dark cutting oil for pipe threading is a good product, relatively cheap by the gallon and should be available at Home Depot.
On a side note there was a garage closing here a couple of years ago, went to look at a press ended up with a really old 5 gallon pail of dark cutting oil, went to use some yesterday, not sure if I bought cutting oil or old engine oil, its black and does;t really smell like cutting oil.

[awemawson]

(12-09-2013, 01:31 PM)PixMan Wrote:

(12-09-2013, 12:41 PM)awemawson Wrote: My 'preferred' width is 2 mm using a Sandvik 151.2-21-20 parting insert holder, and I must confess to pushing too far sometimes on larger diameter stock as I'm too mean to lose more off the stock with a wider blade

Did you know that you can also use Valenite VSG 2.0 N 20 and VSG N2.24 N 20 inserts in that Sandvik Coromant holder (or blade)? Keep an eye out on eBay for deals on those too, could be had cheaper!

Thanks Pixman - a useful tip. I presume that the N in the code is a 'neutral' grind as in the Sandvik one that come L N & R

Andrew

[paulmo101]

Thanks for another great video Tom - most useful.

Does anybody know if the T shaped blades are available in the Uk, I`ve never seen them before but I like the idea of less blade in contact with the work?

Cheers

Paul

[EdK]

It seems like one would need a tool holder specifically for the T-shaped cutoff blades in order to hold it straight up down and not tilted because of the T at the top and the angle of the blade up and down.

Ed

[TomG]

Thanks Paul.

Ed: The tapered and T-Shaped blades interchange just fine. They are both wide at the top and narrow at the bottom.

Tom

[EdK]

(12-09-2013, 05:41 PM)TomG Wrote: Thanks Paul.

Ed: The tapered and T-Shaped blades interchange just fine. They are both wide at the top and narrow at the bottom.

Tom

Tom,

Referring to my sketch below, it shows how I envision the parting tool could be held askew in the tool holder with nothing to bear against on the side because of the T at the top and the angled sides.

Ed

   

[PixMan]

(12-09-2013, 01:41 PM)awemawson Wrote: Thanks Pixman - a useful tip. I presume that the N in the code is a 'neutral' grind as in the Sandvik one that come L N & R

Andrew

Yes, Andrew, that's what it means. There are as well a variety of different chipbreakers on the Valenite VSG inserts. The "FG" is for general purpose parting and grooving at medium to low feed rates. The "CG" is more upsharp, for stainless steels and light feed rates. The "LG" is similar to FG, also good for light feeds. The "GG" is for heavy feeds and interrupted cuts, and the "PG" is their "precision grooving" for just that. It has smaller corner radii. The "RG" and "UG" are both full radius inserts for undercutting shoulders and other round grooves or groove-turn operations.

Valenite grades include 5820, 5735 and UK20. The 5820 is a great all-around all materials grade that can be run at high speeds. The 5735 is a high cobalt content one for interrupted cuts or low speeds, and the UK20 is essentiall the 5820 without coating, great for cast iron, aluminum and stainless steels.

Hope this helps.

Ken

[TomG]

(12-09-2013, 06:18 PM)EdK Wrote:

(12-09-2013, 05:41 PM)TomG Wrote: Thanks Paul.

Ed: The tapered and T-Shaped blades interchange just fine. They are both wide at the top and narrow at the bottom.

Tom

Tom,

Referring to my sketch below, it shows how I envision the parting tool could be held askew in the tool holder with nothing to bear against on the side because of the T at the top and the angled sides.

Ed

It's like this Ed: