Changing the parameters for ballscrew Fanuc 15M

[kningzer]

Hi

I need to change the ballscrew on the X axis in a Fanuc controlled machine.
The only thing is that the oitch on the current ballscrew is imperial and becaus e i live in sweden i want to have it in mm.

Where do i find the parameters for ballscrew pitch?
And does anyone know which more parameters that i have change to achieve this?

Thansk in advance

//Daniel

[stevo1]

Model A or B?

There is more to it then just changing a parameter for a mm ballscrew. You have to take in account the stroke limit and reference parameters will have to be switched as well. I don’t know if pitch error, inclination compensation, and straightness compensation play a factor in this.

I have never switched like that so I guess I am not really the one that should be giving advice on it. I just think that there is going to be a lot more settings and adjustments that need to be done. However if you tell me the model and then PM me your email address I can probably get you the parameter manual.

Stevo

[Al_The_Man]

See PDF.
Al.

[kningzer]

Hi again

It is a B model fanuc. Yeah this is a big job to do. The thing is that the machine is for grinding flutes for cutting tools (ITM is the brand if you heard about it) and we are in a conversion process to make mm a standard in the factory.

I have the reference book and the standard fanuc manuals, but a parameter manual would be greatly appreciated.

Thanks for the pdf, i shall sit down tonight and read it through!

[Al_The_Man]

Originally Posted by kningzer I have the reference book and the standard fanuc manuals, but a parameter manual would be greatly appreciated.

Send me a email address by PM.
Al.

[cnc2149]

Changing the screw parameters is difficult the first time you have to do it as it can ripple through to other parameter settings. Thankfully you have a 15 Model B so you will have flex feed parameters available. If you can post your CNC Parameters file or email them along with your new screw pitch info, I can run the numbers for you.

[kningzer]

Hi

Yeah the firest time is always a b***h ^^

Okay what is the feed flex, don't think i heard about this before.

Sure ill mail you on monday with info, thanks alot

[cnc2149]

Flex feed consists of 2 parameters expressed as a ratio that take the place of the single value DMR that was used in the older, coal-fired controls. You only had 8 values of DMR (Detect Multiply Ratio) in most cases. With flex feed, you have many more possibilities. There are still other pitfalls so I'll have a look at the CNC Parameters. Please list the old and new screw leads in your email reply.

[kningzer]

Hi

here is the parameter file to the machine that we should change the screw in...

http://www.netfear.net/parameters.DAT

[cnc2149]

Your parameters are already set up for 5mm screw on the X axis. See the parameters and calculations below:
=========================

Relevant parameters:

1002 = 0 (metric parameter units)
1004 = 0 (0.001mm LCI resolution)
1020 A3 = 88 (X axis is 3rd in the parameter order)
1807.3 = 0; 1815.1 = 0 (built-in motor feedback is used)
1820 = 2 (Actual CMR = 1)
1876 = 8192; 1891 = 12500 (1,000,000 count motor feedback)
1977 = 1 (flex feed numerator “n”)
1978 = 200 (flex feed denominator “m”)

LCI distance / rev
--- = -----------------
CMR 1,000,000 (n/m)

0.001 distance/rev
----- = -----------------
1 1,000,000 (1/200)


Solve for the Distance/rev:

Distance/rev = 5 mm

[cnc2149]

Note: The formula spacing format doesn't appear quite after it was uploaded as it seemed to strip some spaces.

[kningzer]

Hi again

Sorry for the enormus delay to my answer and thank you all for your patience.

I have Changed the parameters and now and it is working fine.

Thanks for all the help, im really glad for this!!!