Messages

1

General Mach Discussion / Re: Mach3 backlash speed question

« on: October 12, 2019, 06:31:47 AM »

Consider the the 50% value a  suggested  starting value. I question  setting the the value higher or lower will help much. Play with the setting as you wish. Inertia of the table should not be a problem if the axis has adequate power to move it for desired operating conditions. 

Backlash can vary, no backlash would be ideal, so I will say that one should minimize
the backlash, but to do that, you need to know what is causing the backlash.
Consider:
- Idealy a ball screw should provide linear movement over the total length of the screw.
   You would need to profile the total screw screw travel in both directions to know  what you
   actualy have.
- What part of the backlash is caused by the nut?
- What part is caused by support / thrust bearings? Often overlooked but can be a large
   contributor to backlash.
- Any axis component involved in moving the axis contibutes in some way to backlash.
 
I must also remark that the steps per and tuning should have been set /tested with  backlash
removed.

Recall that the smallest theoretical move that you  can do is equal to  1 over the steps per unit. Unlikely that  you can accurately move at theoretical value or measure that  movement accurately.

In general any adjustment done ie; bearing pre-load, gib adjustment, etc should be done in a way that the total torque required to just move the  load is minimized  and the remaining torque is maximized.

RICH

2

General Mach Discussion / Re: Automatic setup of steps per unit

« on: October 02, 2019, 09:16:40 AM »

Echoing Brett and Graigs  replies,

1. One should always calculate the steps per unit and understand that the number of steps
     calculated is theoretical. 
    - Learn how to calc the steps per, no excuse's!
 
A link to a steps per unit caculator:
https://www.machsupport.com/forum/index.php?topic=16315.0

2. You must confirm the calculated steps per unit. Understand, that when you test, quality of axis components and their installation come into play. The testing is only as good as ones ability to accurately  setup and  measure a distance based on a physical standard and the method they use. For example:
Theoretical resolution for a  steps per unit of:  20,000 ( 1/20000) = 0.00005"
                                 "                  "           : 253,000 = 0.000004"
? is your axis components linear travel that accurate and can you measure to actualy know.
? How much total backlash do you have and is it consistant? ALL axes have backlash it's just a
   matter of degree. Total backlash is the sum of each individual axis component non
   movement( ie; screw with nut, belt, coupling, gears, etc.) and each can vary depending on
   operating conditions.

Practical setting of the steps per unit  will be  a value that satisfies their machines  overall  machining accuracy. The value can be as calculated, as physicaly tested, or a value close but different than both of those.

3. Think of the wizard as a software assist to check / adjust the calculated to the tested.     

RICH

3

Mach Screens / Re: LIcznik

« on: September 28, 2019, 12:01:41 PM »

Seba,
How to do screen modifications starts with  you  downloading the screen editor.
I gave you the link. Then view / study the tutorials and videos on that site.

I assume you are using the standard Mach3 mill screen which is 1024.set.
Make a copy of that file and place it in a safe place.

Now you must go through a learning curve,
Open the mill screen using MachScreen. 
Click the Help Tab and review all the help.
Play around with all the controls, etc, but don't save anything when you exit MachScreen.

I suggest you download and review the Mach Customization Guide and Macro Programmers reference Manual.

 Ask questions after you do the above.

Yes, someone can do what you want quickly ,BUT, it's better that you learn.

Have some fun with the learning curve ,

RICH

 

4

Mach Screens / Re: LIcznik

« on: September 28, 2019, 04:46:44 AM »

Seba,

Not sure what you mean by "counting of elements".

If  that relates  to your other topic

https://www.machsupport.com/forum/index.php?topic=41800.msg273153#msg273153

Then you  can use a screen editor called MachScreen by K.Dietz to modify a screen set used by Mach.

LINK: https://kd-dietz.com/

RICH

5

General Mach Discussion / Re: New to Mach - need help with installation & set up

« on: September 27, 2019, 04:51:30 PM »

Had to delay paying jobs and turn down other paying jobs to put more time into mach. We have it making parts again but the next time mach or windows fails us we will switch this mill over to linux cnc

GEZ
Sorry for your experience, BUT, you had "a few years ago" /  lots of time to know learn how to configure a machine using Mach. Glad you got it working.

Only you can decide what control system you want to use.

This forum is monitored  24/7 and replies to problems or request for help is prompt. Knowledgable and experienced forum members  do a great job of assisting folks and do so for the high pay of not even a thanks!

Lack of buisness planning to accomplish a task is the owners reponsibility and not the fault of  someone or something else.

Wishing your buisness well,

RICH

6

General Mach Discussion / Re: command to home one axis only

« on: September 27, 2019, 05:44:17 AM »

g28 homes all 3 axises Is there acommand to home an individual axis like saying " home the x axis" (dont do anything to the others)


Fred,

G28 by itself in Mach3 provides for  movement  without axis definitions resulting in a transverse move to machine zero. As noted in Mach definitions, the intermediate point is the current point and only one movement is made when no axis words are given.  One must be careful in it's use since G90, G91, and additionally Fixture Offsets can affect the resulting machine movements when G28 is commanded.

To home an individual axis, say X axis, add axis definition to the G28 command for example:

G28 X0.0 - if a G54 / work offset exists and you are away from the exact offset value then you will have two movements. IE; it will first go to the intermediate value ( the work offset value ) and then go to X axis machine zero.

G28 X0.0 – if G54 exists and you are at the exact offset value then you will have one movement ie; since your at the intermediate value there is no need to move to it so one move only to the X axis machine zero.

G28 X0.0 – if no offset exists there is no intermediate movement and the axis just goes to X axis machine zero.

G91 G28 X0.0 – there is no movement since mode is changed to incremental and the request is for zero movement

G28 – only one movement back to machine zero irrelevant if there is a work offset

Take some time and try the G28 along with axis definitions and see note the movements that occur.
Try G28 X1.0 for example and see what happens!


RICH

7

General Mach Discussion / Re: mach3 turn threading issue

« on: September 18, 2019, 05:14:52 PM »

Russ,
So the board uses G33, not G32, and the G76 of UCCNC board uses a G76 command, but must add, that the G76 command is different as compared to the MACH3 command.

?
RICH

8

General Mach Discussion / Re: mach3 turn threading issue

« on: September 18, 2019, 05:04:03 PM »

im just trying to find out if the problem is using uc400etc or the index detection isnt good enough  my max rpm is 2500

Your problem is that you don't understand what the  UC 400ETH requires in order to do threading and the required configuration of the external controller  board. One would think that UNCNC would provide specific instructions on how to use that board with MACH. Usualy there is a specific plug in provided for use of the board along with MACH.

There is a manual for the UC400ETH but the site didn't list a UC400 users guide  like it has for the 100 and 300. There are utility files for the UC400ETH.

Using a Hall sensor is just providing an index and is not the same as using an encoder  as BR549 remarked.

RICH

9

General Mach Discussion / Re: mach3 turn threading issue

« on: September 18, 2019, 06:37:01 AM »

chessie,

You are using an external motion device and should have said so right from the get go.

Have no experience with the UC400 ETH controller. There should be a installation
and user guide available for use with Mach from the seller / manufacturer. There are product downloads available
for the 400. Did you have a read of that info?

If someone has experience with  UC400 ETH they can help you and may reply
here. If not,  I would suggest that you go back to the manufacturer for  specifics.

The mach3 threading pdf does not address the UC400 ETH.


RICH

10

General Mach Discussion / Re: mach3 turn threading issue

« on: September 09, 2019, 09:05:45 AM »

chessie,

Info on debounce see attached file

RICH