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Introducing both Manual Lathe Machine and CNC Lathe Machine (Computer Numerical Control)
Center Lathe Machine
image credit: Wikipedia CC3.0 Licensed
Manual lathe machine as the name implies is when machine operations like shaping, drilling, boring, facing etc. are done manually with the full help of an operator who will manually balance the the work piece and work tool for effectiveness and also manually apply coolant on the materials.
Typical example of a facing operation on a manual lathe machine
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While the CNC lathe machine as the name implies Computer Numerical Control is a machine that does machine operations too like facing, drilling, shaping, turning and the likes but it is Numerical controlled I mean it runs on programs where you have to type in a program to run the operation and wait for the magic
ps: Computer Numerical Control is not just applicable to lathe machine
CNC makes machining fast and precise, having a manual lathe is not a bad idea but getting to use a CNC lathe and know what it feels like you love to consider a CNC lathe machine. At a point in ones life we just have to see what have been done before and then also follow the trend, personally before I could understand how to program a CNC lathe I understood the principles behind lathe machine and I was very conversant with the manual lathe machine.
Some of the advantages of CNC lathe are consistency, accuracy, production cost and it is possible for a operator to work with less experience.
You might be wondering why I said less experience because you are meant to have a good knowledge of how the machine works but I have my points to that. There are complex jobs you might want to carry out and it is only a skilled operator that should be able to perform such task but might not be that skilled but the CNC help you out provided you know the right Numerical codes to run the operation. I would have love to say it a small idea of artificial intelligence but it does not have a mind of his own because it works strictly on instruction and there something called dry running using softwares like G-Simple, CAMotics e.t.c where you have to do a simulation of the operation first and see the shape you intend to on a monitor before you fix in the work piece for the actual job but on the manual lathe you just have to start the job and if there is a mistake along the like you have to start all over with another workpiece of the mistake cannot be managed and that is where the precision comes in.
Computer Numerical Control lathe machine in details
CNC lathes are going to replace the manual lathe machines due to the flexibility in operations, repeatability and accuracy.
CNC machines are designed to make use of modern carbide tooling and totally use modern processes. The Numerical programming that the CNC lathe runs on are CAD/CAM processes or programming manually by the operator who has the knowledge of CAD/CAM and the uploading to the machine and finally the result of the program is produces from the occasional supervision of the operator.
The machine uses electronics via computer menu style, the program can always be edited and displayed at the on the digital display machine monitor and along with a simulated view of the process that was gotten from the dry running like I explained above.
With rapid growth in this industry, different CNC lathe manufacturers use different user interfaces which sometimes makes it difficult for operators as they have to be acquainted with them. With the advent of cheap computers, free operating systems such as Linux, and open source CNC software, the entry price of CNC machines has plummeted.source
More information about the CNC 👇
LATHE MACHINE EXPLAINED
Example of making a shaft if this nature
Image source : Screenshot from my lecture note
With a CNC LATHE, this is turning operation that can take you minutes if not up to an hour on the manual lathe but with the computer numerical control lathe I just need a code below which I will write now and explain
Solution to above tasks to be carried out on a lathe
N05 M03 S1300
N10 G00 X22 Z2
N15 G01 X21
N20 Z-20 F50
N25 G00 X22 Z0
N30 G01 X20
N35 Z-10 F50
N40 G00 X22 Z2
N45 M30
The program above will produce that shaft
M03 means rotate the spindle on a clockwise direction
S1300 means at a speed of 1300rev/s
G00 means Positioning at rapid speed
X means the direction to cut and the figure in front is the dimension
Same as Z and also Y if the operation is that complex to have all the directions
N means the numbering of the program lines which can be in any form like multiple of 2 or multiple of 10 and so on
G01 means Linear interpolation
F50 means the amount of feed to take of from the material.
M30 ends the program.
More of the codes and meaning can be found 👇
Common G codes and M codes for CNC machine controls
Conclusion
The manual lathe is awesome and really interesting to work with if you are an expert just like driving a manual car and an automatic car, some people feel the automatic cars are for those that can't drive and are lazy. Same is applicable but here there is a this feeling you get when you know there is 98% perfection on a job to be done for a client.
If your are very good with manual lathe machine please give the CNC a try.
Added Information and references
Different between the manual lathe and CNC lathe machine
CNC lathe machine over manual lathe