cone at lathe machine

[waqasmalik]

Hi all, please find attach figure.Its of cone.Material is MS.Till now i have machined round jobs at lathe machines.I am novice in machining.My boss has given me a task of machining this cone on lathe machine having threading at one end (shown red). Raw material will be a rod of MS. Plz tell me the processes involved in machining it.I wll be greatly thankful to you all.
waqas.

 

[waqasmalik]

My idea is to machine threading in the raw material first and make its male part having threading at one end and some unthreaded cylindrical portion at other end and engage it with the machined threading in raw material.Clamp unthreaded portion in the chuck and start taper turning.
Am i right?

 

[berkshire]

If the larger diameter is capable of being held in your lathe chuck, that is unneeded.
Just drill and tap the threaded part, set the angle on the cross-feed for the taper, then part off the resulting cone after changing the tool.
B.E.

You are judged not by what you know, but by what you can do.

 

[ornerynorsk]

What Berkshire said. This is an easy part, provided you have the tooling. Learn by doing, scrap parts have value in that they teach you what you did wrong so you don't do it next time. MS=mild steel?

It is better to have enough ideas for some of them to be wrong, than to be always right by having no ideas at all.

 

[BillPSU]

What is the diameter of the large end of the cone?
Does your CNC lathe have a barfeed attachment large enough to handle raw material used to make this part?

Depending on your answers the process could be
1. Push the material out.
2. Face end of part.
3. Rough and finish turn taper.
4. Drill hole
5. Bore hole
6. Single point thread
7. Part off.

Otherwise the part will have to be sawed to oversize length.

First CNC Lathe operation
1. Chuck on oversize end of part.
2. Face end of part.
3. Rough and finish turn taper.
4. Drill hole
5. Bore hole
6. Single point thread

Second CNC Lather operation
1. Screw on part to thread.
2. Face off oversize end of part.

Bill

 

[ornerynorsk]

Threading a partially finished part onto a threaded mandrel in order to finish the part, in theory, might seem like a good idea, but in actual practice this is generally not a good idea.

It is better to have enough ideas for some of them to be wrong, than to be always right by having no ideas at all.

 

[BillPSU]

I agree screwing the part on a threaded mandrel is not the best process however when the complete OD is tapered I don't think you have a choice.

Bill

 

[berkshire]

BillPSU (Industrial),
The OP did not say he had a CNC lathe, and I agree, with, a CNC the cone would be a lot easier. He also did not say if he had to build more than one part.
The fact is that, if, he can do the operation without un-chucking/re-chucking, he will end up with a more accurate part.
Also if, he can feed through, with the right tool he can part off and face in one operation ready for the next drill and tap operation if needed, if he did have to make more.
If he cannot do that, then he is faced with a part off operation, and a waste piece remaining in the chuck.
B.E.

You are judged not by what you know, but by what you can do.