The Elsmar Cove Business Standards Discussion Forums More Free Files Forum Discussion Thread Post Attachments Listing Elsmar Cove Discussion Forums Main Page
Welcome to what was The Original Cayman Cove Forums!
This thread is carried over and continued in the Current Elsmar Cove Forums

Search the Elsmar Cove!

Wooden Line
This is a "Frozen" Legacy Forum.
Most links on this page do NOT work.
Discussions since 2001 are HERE

Owl Line
The New Elsmar Cove Forums   The New Elsmar Cove Forums
  Measurement, Test and Calibration
  Calibration of CNC Machines

Post New Topic  Post A Reply
profile | register | preferences | faq | search

UBBFriend: Email This Page to Someone! next newest topic | next oldest topic
Author Topic:   Calibration of CNC Machines
Bob
Lurker (<10 Posts)

Posts: 4
From:Jacksonville, FL, USA
Registered: Nov 1999

posted 29 October 2000 08:30 AM     Click Here to See the Profile for Bob   Click Here to Email Bob     Edit/Delete Message   Reply w/Quote
Does anyone have written documentation procedures on how to calibrate CNC machines to ensure that produce consistent product?

IP: Logged

CJacobsen
Forum Contributor

Posts: 48
From:Williamstown, MA
Registered: Oct 2000

posted 29 October 2000 09:31 AM     Click Here to See the Profile for CJacobsen   Click Here to Email CJacobsen     Edit/Delete Message   Reply w/Quote
In my experience (working with a Machine Tool Manufacturer a few years ago - lots of CNC machines in this facility) when calibration of these machines came up, the manufacturer of the machine had supplied the alignment and calibration procedures and in fact for most of the machines, these procedures could be found in the Technical Manuals. I would check these two places first. These are procedures that are performed usually during the initial installation and set-up of the machines.

Even though most machines came with a 'Test' program, this facility developed their own 'test' program for each machine that related to the parts they were actually producing. This program was used in conjunction with written instructions for setting up the machine to perform the test. This procedure (written instructions and test program)was run after the initial set-up, calibration and alignment of the electronic and mechanical systems was performed. Depending on the machine, the program instructed the machine to produce a part or machine raw material to a specific size, pattern, shape or whatever, and then this was checked using standard micrometers, calipers, gages, etc. and the data recorded.

One aspect determined to be a big factor in the machine passing the 'test' program test, was the tooling currently in the machine. After many runs, it was determined that the actual cutting edge of the tool being used contributed the most error or variance in the piece being produced as opposed to the finite movement and placement control of the cutting tool.

Subsequent checks of machines were done using this test program and written procedure only. Cycles were every 3 or 6 months. This cycle was determined mostly by the production rate of the machine. If the part was produced to size/spec., the machine was considered 'in cal.' If the part was not produced properly, the full calibration/alignment procedure was performed.

Hope this helps.

------------------
Christopher E. Jacobsen
cej@cjsys.net
CJSystems

[This message has been edited by CJacobsen (edited 29 October 2000).]

IP: Logged

CJacobsen
Forum Contributor

Posts: 48
From:Williamstown, MA
Registered: Oct 2000

posted 29 October 2000 09:54 AM     Click Here to See the Profile for CJacobsen   Click Here to Email CJacobsen     Edit/Delete Message   Reply w/Quote
I should add that some machines were tested more frequently than the 3 or 6 months stated above. This facility had 110 or so machines. Generally the smaller machines were tested more frequently - two weeks to 1 month cycles. This was due to the heavy production load and nature of the machines.

Tool life was also monitored and tooling was changed based on number of cuts or time in service as opposed to when it got dull (of course it could be changed any time sooner if warranted.) This was to prevent the tooling from getting worn to the point that the variance introduced was unacceptable.

------------------
Christopher E. Jacobsen
cej@cjsys.net
CJSystems

IP: Logged

All times are Eastern Standard Time (USA)

next newest topic | next oldest topic

Administrative Options: Close Topic | Archive/Move | Delete Topic
Post New Topic  Post A Reply Hop to:

Contact Us | The Elsmar Cove Home Page

Your Input Into These Forums Is Appreciated! Thanks!


Main Site Search
Y'All Come Back Now, Ya Hear?
Powered by FreeBSD!Made With A Mac!Powered by Apache!