turning small diameters, improving finish - dnmg general turning insert with small nose radius

I went to the Khari Baoli spice market in Delhi one summer evening, in search of pickles for myself and walnuts for a friend. It’s a street full of shops selling spices, pickles and dry fruits.

RDG Tools Catalogue | Carbide Inserts for Lathes and Milling Machines | Screw Cutting / Threading Inserts | 11 ERA / NRA Inserts for 10mm / 12mm shank tools |  5PC INDEXABLE EXTERNAL THREADING INSERTS 55 DEGREE IMPERIAL 11ER55 11MM

You can actually increase the depth of cut to these values if there is spindle power and torque available, as explained here: Maximizing spindle power usage.

RDG Tools Catalogue | Carbide Inserts for Lathes and Milling Machines | Screw Cutting / Threading Inserts | 11 ERA / NRA Inserts for 10mm / 12mm shank tools |  5PC INDEXABLE EXTERNAL THREADING INSERTS 55 DEGREE IMPERIAL 11ER55 11MM

CADEM CAPSturn CNC lathe programming software takes insert max. depth of cut into consideration and helps you reduce cycle time. It is a simple and affordable CAD/CAM software.

We decide the depth of cut on the basis of an arbitrary thumb rule. E.g., in rough turning we’ll always use a depth of cut of 3 mm. Why not 4, 5 or 6 ? Nobody knows. Just a bad thumb rule that makes your lathe a white elephant.

The pickle collection in my home (about 15 types – pic. above), at one time has now reduced to about 5 types for health reasons.

Khari baoli means the ‘well of salt water’. The market, near Chandni Chowk, was built during Mughal times, during the reign of Shah Jahan. The step well after which it’s named was used for animals and for bathing, and got covered up sometime in the past 350 years.

RDG Tools was started up by Richard Dickinson in 1992. We started exhibiting at model engineering exhibitions in 1994 and realised from the shows that people wanted quite specialised tooling for their machines and also a wide range of tooling which they could adapt to suit their needs.

Here’s a little-known fact about inserts. They have a maximum depth of cut based on their shape and size. In roughing operations, doubling the depth of cut halves the cutting time, enables you to use the machine’s spindle motor better, increases your profits. By using an arbitrary thumb rule we are under-utilizing the insert and more importantly, under-utilizing the machine. See this post for more on this : CNC spindle power and ROI.

By the way, speaking of spice, at one end of Khari Baoli road is GB Road, Delhi’s biggest red light area, also in existence since Mughal times. Named after Garstin Bastion, a British Collector of the time (by the way, Garstin, could you have ever guessed what they were going to name after you ?)

A place worth seeing even if you’re not a fan of any of these. Amazing colour, energy and chaos. Also an amazing variety of pickles. You actually sneeze a lot, because of the spices floating around in the air.