×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

Optimum Cutting Speed, Feed and Depth Of Cut calculation

Optimum Cutting Speed, Feed and Depth Of Cut calculation

Optimum Cutting Speed, Feed and Depth Of Cut calculation

(OP)
Everyone,

Need some advise on how to calculate the optimum cutting speed, feed and depth of cut for machining:

Operation - Facing BUT "NOT single point cutting" - It is "Plunge Facing" with R5 Insert

Machine - Vertical Lathe

Job Specifications - variable diameters and thickness.

How would we be able to determine job rotation speeds and feed rates to get optimum tool life and better machining?

RE: Optimum Cutting Speed, Feed and Depth Of Cut calculation

Call your supplier - they can usually be very helpful!!

RE: Optimum Cutting Speed, Feed and Depth Of Cut calculation

Figure out what you want, first.

Some people like to buy cheap inserts and make them last forever. Think hobbyists. Some people want to run as fast as possible and don’t care how long the inserts last. Think Boeing trying to optimize output from a $50 million dollar mill

An awful lot of time and money is lost in the world every day because purchasing / management thinks tooling is expensive but machine time and labor are not important.

Start with Machinery Handbook, the cutting tool supplier's recommendation and the material supplier's recommendation then experiment.

Put a really good operator on it, one who is very familiar with the machine. Get QC involved for cut quality.

Find out just how strong your fixturing is before you start.

Thomas J. Walz
Carbide Processors, Inc.
www.carbideprocessors.com

Good engineering starts with a Grainger Catalog.

RE: Optimum Cutting Speed, Feed and Depth Of Cut calculation

There are some many variables which you have not defined.

What is the material? What condition annealed, normalized, heat treated? If this is a casting is there inclusions(cast austinetic stainless)?
How rigid is the setup?
How long does it take to change a tool?
What is the cost of the raw material(part)?
What is the hourly rate on the machine?
What is the hourly rate of the man?

You will have to determine your optimum costs. Rigidity of the setup and material are probably your most important parameters starting out then with experience machine and labor costs become the deciding factors.

High dollar part costs will also drive you to never have a catistrophic insert failure insert failure which scraps the part.

Good Luck
Bill

RE: Optimum Cutting Speed, Feed and Depth Of Cut calculation

(OP)
thanks everyone,

More than anything else right now I would be only interested in theoretically calculating speed and feed data to determine if we indeed are somewhere near those. The suppliers in India are not much useful as they tend to do more trial and error than have any justified theoretical logical behind them.

Yes, do understand the calculated values would vary in practical conditions but believe they should be used as a basis behind any judgement.

RE: Optimum Cutting Speed, Feed and Depth Of Cut calculation

It has been many years since the company I used to work for had parts machined in India.
We asked them how they arrived at their speeds, and feeds? The answer came back, "we run the feed up until the tool breaks, then back off 10%.".
B.E.

RE: Optimum Cutting Speed, Feed and Depth Of Cut calculation

CutPro and ShopPro softwares are commonly used in industry to answer these questions.
If you're working for a large company then it would be possible to acquire such softwares.

RE: Optimum Cutting Speed, Feed and Depth Of Cut calculation

You can compare heterogeneous cutting operations by keeping track of the Metal Removal Rate, measured as volume removed per unit time. All operations for a given part material and a given cutter material should approach the same limiting MRR, providing that other factors like spindle speed, spindle power, chip clearance, or cutter rigidity do not interfere.

It's not the only thing you should measure, but it can help you find process steps where there's room to improve.


Mike Halloran
Pembroke Pines, FL, USA

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources