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Re: A-axis rotary lathe question for Mach 3
« Reply #40 on: November 07, 2017, 07:58:02 PM »
Gary,
May want to start a new thread about use of that PLC for a turn / mill combo.
I assume your are aware of Simpson's work on the matter.
Would make for an interesting topic.

RICH

Was not aware of Simpson's work, got a link?

Offline dude1

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Re: A-axis rotary lathe question for Mach 3
« Reply #42 on: November 08, 2017, 01:40:14 AM »
Yep,
Send me a PM with your shipping address. It's tiny, like 2" square.  Don't remember what I paid for it but it wasn't much, doesn't matter.
Gary I sent an email to you personally on 11/5/ or 6 /2017.  Did you receive it?   bob
Re: A-axis rotary lathe question for Mach 3
« Reply #43 on: November 08, 2017, 01:59:53 AM »
Now asking for G-code help.

I want to write a g-code line in MDI where the Y-axis moves .125 inches while the  4th-axis lathe moves one revolution.  That should not be too difficult, but I have not been successful to date...and I would like to figure this out in the next 3 days... I've spent a week already unsuccessfully.  Here is a typical line of code and the results.

G1 y-.125 A360 F10.000  Lathe started making a clicking sound, Y did not move and the lathe rotated about 1/2" of distance on the 3" diameter log (material).  I did not ruin the log as I had Z at home position up and away from the material.

2nd Try
G1 y-1.000 A2880 F3000
The lathe turns about the speed I would like for wood, but if it actually had the z spindle turning, it would cut a nice spiral, with about 1/2" between each turn of the spiral, whereas I am trying to get the spindle to "true" the wood log.  So the mill end would have to remain at the same Y position for the time of one revolution before Y advances .125 inches ahead down the length of the Y axis...   Now at F3000 the lathe will make one revolution in 7 seconds... I just need to get the y movement slowed down.

OK Guys, please help me with the G-code... bob

Offline RICH

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Re: A-axis rotary lathe question for Mach 3
« Reply #44 on: November 08, 2017, 07:31:33 AM »
Bob,
Would not it be better to have a clear understanding of various configurations and the affects of some settings before you code?

Anything really important about the next 3 days?

Note that in school your using Haas, yet Smid's book is Fanuc ( Mach 4 is Fanuc based ), Mach3 has a dialect of code which is  say similar but dose not have some of the commands of other controllers. Don't want you to get all screwed up in your head!

RICH

Re: A-axis rotary lathe question for Mach 3
« Reply #45 on: November 08, 2017, 11:47:30 AM »
part of my class project is to produce on cnc a guitar bridge... I had to get special permission to do this... I think that class runs up to xmas break... but right now the "log" has to be "trued" so that I can cut a flat across the length of the log that holds the guitar bridge material...and so I would not want to flunk the course if I don't even get the thing made.  So that is why the pressure...and of course the whole idea is to get codes written for all my guitar parts...  now I do know that is a big order in terms of learning curve.  Also, though, the g-code help I am asking for cannot be that complex... one or two lines.  Of course I will continue to learn and develop along with others on the forum...I like doing this.

So maybe you could help me with one turn or revolution of a-axis and at the end of that my mill end moves .125 inches in the -y direction.  Can mach 3 not do that... is it limited in some way??

thanks, bob

Offline RICH

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Re: A-axis rotary lathe question for Mach 3
« Reply #46 on: November 09, 2017, 11:13:36 AM »
Bob,
I will help with the commands.
BUT
It will not be a "type this in the MDI line" kind of thing and you try it out.
Instead you will walk a "learning path", it will start with basics, and progress should be quick.

Just going to be my way of getting you somewhere quickly and having you KNOW what your doing.

So you want to have some fun........?

RICH




 
Re: A-axis rotary lathe question for Mach 3
« Reply #47 on: November 09, 2017, 12:24:43 PM »
Rich--Yes of course... I never turn down an offer to learn like that.  bob

Offline RICH

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Re: A-axis rotary lathe question for Mach 3
« Reply #48 on: November 10, 2017, 08:07:47 AM »
BOB,

I will assume that you  have not changed any of your Mach settings and your still using the xml file that you posted.  Copy the xml to the Mach3 directory and rename the copy it to 4thbobmill.xml. We will  be doing changes to your configuration and will use the "4thbobmill" profile.

- Per your xml you are using the A for the rotary axis. It is currently defined in Config >General Logic Configuration as linear. Tick the box for A to make it angular and then Save Settings.Now you will need to change your motor tuning. So caluculate the steps per ( the units are degrees for an angular rotary axis ).

Example Calc:
For my rotary using micro stepping and a 72 gear ratio:
200 steps / rev X 1 rev /360 degrees = .5555 steps / deg X 10 micro steps X 72 gear ratio=400 steps per unit
 
- Note the value you calculated but use a value of  50  less than you calculated as an imput for the steps per.
in motor tuning. Use 10 as value for the velocity and 2 as an acceleration value.

- Now define which keys you will use to jog the A axis.
Config>System Hot keys Setup, click the A /U++ box and hit the key you want to use. Do the same for the A/U--. Make sure the keys codes are different than the other axis keys.
 
- Save Axis Settings and also Save Settings under Config.

- Hit the Tab key, and in the flyout set Jog Mode to Cont Jog the rotary to see that it rotates. 
Go back to motor tuning for the A axis and keep changing the velocity value by doubling
the velocity value and jogging the rotary. Do this until the stepper skips.  So 10,20, 40,80,160, 320, etc.
Suppose it skips at 320 then set the velocity  to 160.

- Now start changing the acceleration value with the velocity set at 160 increasing the accel. Do similar as the you did for the velocity increase. So 2,4,6,8,10 etc. for values. Acceleration becomes important in 3d work.
See where the  axis skips. Go back one trial setting of accel, so if skipped at 10 go back to 8.

- You now have found the max velocity and accel settings for your rotary. Note that as the stepper rpm is increased the torque decreases and you need to have adequate torque for machining. Reliability is more important that speed.

Save Settings and exit MACH.

------------------------------------------------------------------------------------------------------------------

- Download the following manuals:
  Using Mach3 Mill
  Mach3 CNC Controller Software and Installation Configuration

- read / refer to in  the Using Mach3 Mill Manual info on:
  - read section 5.5, 6.2.3, 6.2.12,10.1.5 and 10.1.6
  - Gcode commands: G0,G1,G90,G91 then G93,G94,G95 ( You may want to compare Haas command                definition to the Mach3 defintions of the commands)
- read / refer to in Mach3 CNC Controller Software and Installation Configuration
  -  Section 5.5.2.3
  - Page 5-37  about Rotational: settings
  - Page 5-39  about Axis DRO Properties

--------------------------------------------------------------------------------------------------------------------------

To be continued,

RICH
Re: A-axis rotary lathe question for Mach 3
« Reply #49 on: November 10, 2017, 10:04:26 AM »
Rich,
Good write up. Another thing to remember with a rotary axis. Unlike a linear axis the cutting force available varies with the radius of the work. Milling on a small diameter part may work fine, but you could experience stalling on a large diameter part making the same cut.