What secret options in an OMD control system, helix?

[BrianSP]

Hi Guys,
I'm new here obviously. I am completely new to CNC machines so I am incredibly pleased to find a site with so many helpful people and so much knowledge.

I have a Kent bed mill with a Fanuc OMD control system that I run from Dolphin CAD/CAM. I think I will need a memory upgrade because the Dolphin CAM produces masses of code for any helical move.

Because of my memory problem I was interested in the posts concerning upgrades and "optional" modes that are built into the Fanuc control system. Is there likely to be any helical options on my control system that could be turned on? Does anyone know what options are asleep in the control system or is this totally maker dependent? In view of the age of the control system can I still get the options activated?

Thanks, Brian

[Al_The_Man]

The Helical can be turned on by parameter but you also need the spindle encoder and spindle controller capable of using the feature.
Al.

[BrianSP]

Thanks Al.
The machine has a notched belt drive from the VFD motor to the pulley/spline assembly.
There are no connections to the spindle cartridge or the pulley assembly that I have seen. There are some extra wires going into the VFD motor that I have not identified (no circuit diagram).

Does the spindle controller card need to know a simple rotation count (ie 1 pulse per rotation) or does it need to know exact spindle angular position?


No point in getting excited about options if I do not have the hardware. I will investigate further thanks.
Brian

[Al_The_Man]

In most commercial CNC's with this capability there is feedback from motor to Spindle controller or VFD etc, and also an encoder on the final spindle shaft, this encoder is used to gear the Z axis motor off it, for tapping or helical operation.
Al.

[BrianSP]

Al, hope you see this

I am lucky in that I have a complete set of manuals with my machine. The Fanuc "Operations" and "Maintenance" manuals plus the "Manufacturers" manual.

I checked my machine. it is fitted with a A16B-2201-0103 memory card that includes connector M27. The book shows some sort of spindle control on the memory card and also shows M27 connecting directly to something called a "Position Encoder" apparently attached to the spindle intermediate drive (on my machine where the belt pulley adapts to the spindle splined shaft). The card diagram says this is an "analog" spindle arrangement.

A further nearby diagram showing pin connections titled "Position Coder Interface" shows M27 connecting to a unit called the "Position Coder". There is no part number on the position coder block.

It looks to me that if I can find a "Position Coder" and a suitable cable then I can get my mill operational in true helical movement (after paying Fanuc's extortion). The manufacturers manual actually lists G codes 33 and 95 in their g-code list.

Thanks for the info provided so far.

Brian

[Al_The_Man]

The encoder is a standard differential encoder, IIRC the resolution is 1000cts/rev, I will see if I have the info.
The other information I sent you may not require Fanuc getting involved.
Al.

[dcoupar]

Originally Posted by Al_The_Man The Helical can be turned on by parameter but you also need the spindle encoder and spindle controller capable of using the feature. Al.

Just curious, Al.

Why would he need a spindle encoder for helical interpolation? It's just 3-axis milling, isn't it? I understand if he wanted rigid tapping, but I could swear I've done helical on old Matsuura's that didn't have spindle encoders.

Please enlighten me, o Swami...

[Al_The_Man]

Yes your right of course, For the last few weeks I have been working on writing a threading routine for a lathe and somehow it given me a brain freeze.
Thats my excuse anyway.
Helical milling involves 3 XYZ axis interpolation overall.
So Brian, you may be able to get away with the info already supplied!!
Al.

[BrianSP]

dcoupar

I'm new at this but my original need was to reduce the amount of code generated by my CAM program for threadmilling. Someone was kind enough to write a sample threadmill example for me and the threading part of the program took 3/4 of the code yet most of the actual work was contained in the first quarter. Since the helical interpolation would be built into the CNC I am imagining that the amount of code required to threadmill would be much reduced. Would this be correct?

If helical would help me out I am really interested in this since my present project involves cutting a couple of largish diameter none-standard threads to match the threads on parts made by suppliers so I am focused on threadmilling right now. A memory upgrade is in the future also.

Actually my original question was more generic. I was just wondering how many options there were on the OMD control since I have never seen these mentioned until I joined this forum and there is no information in my manuals.

Learning as much as I can about codes and machines is great in itself.

Brian


.

edited for crossing posts.

Thanks Al, the more I learn the better.

[dcoupar]

Brian,

Yes, helical interpolation will give you much smaller programs than a bunch of linear moves approximating a helix.

Just out of curiosity, have you tried to MDI in a helical move? Position XYZ in the middle of the travel, then execute the following in MDI.

M03 S200;
G3 G91 X1. Y1. J1. Z0.5 F20.;

See what happens when you hit cycle start. If you don't get an "Invalid G-code" alarm, then the helical interpolation option is probably turned on. Let us know.

There are dozens of options in the control that you probably won't see much about here because the owner of CNC Zone has asked that we not post proprietary information (such as Fanuc options) on the site. This was "suggested" by Fanuc's lawyers.

Dave

[dcoupar]

Originally Posted by Al_The_Man Yes your right of course, For the last few weeks I have been working on writing a threading routine for a lathe and somehow it given me a brain freeze. Thats my excuse anyway. Helical milling involves 3 XYZ axis interpolation overall. So Brian, you may be able to get away with the info already supplied!! Al.

Al,

Brain freeze? You? I doubt it. Brain fatigue, maybe. My suggestion is that we should all take Fridays off from now on.

Dave

[BrianSP]

I am not trying to dodge Fanuc's control. I was just wandering what options there may available be that I did not know about. Not making this information easily available is a bit like having a retail store and never unlocking the door so potential customers can see what you have for sale. I have the full OMD manuals, Fanuc and manufacturer, and none of them mention available options.

Dcoupar, I will try your suggestion. Since I bought my mill used I have no idea what options may be on or off.

Does Fanuc still support options for a 2000 machine?

By the way - Fridays are "off", that's the day to play with my new toy